ae! Bs 1} ne Rhy SY) ta) ks ae a Lo iit ie - . ae ir baat Ys o ee Wiis ti f ia s) iB : athe Gos) i Bite “i i uy + yey ity, x ie i ANE CMY ETAL NevAtunas aah Aas ee a . aie Seiyr Bs SNH Sth M mae i : 7 ui 942 iS Dyed pine ehie ee ae ohags ea athe j We a iy, ae — et eas i) } bars in a) Lf in i 17 ' 4 i ‘ i \ i { wi 7 i © i f a f } UP f Ud JORDI Le Ne eee + PR |, Me an oe aye Me "| ‘i ia A renah Ue ae eh hee i Bits Li, wv Aye it rae fees ie vein x vn we Mg cient ” ie ia i eat ihe sie en Rare “a y nes Lav) i he HS 4 1) on yi ip i be THE AMERICAN JOURNAL OF PHYSIOLOGY VOLUME XLIX —— Ss IS BALTIMORE, MD. 1919 Si te ORR ec! "55 Sea a aa ih v ear’ ae Oe 2 ' 4 - ‘ee - , ) of a ays * 4 ra}: Yi - ¢ ' os § : Bs xs eye i: : TAATVIOU VADLS YOOAOL VRE t or + ; a co ; ry a0 : ‘ na 7 J tI] ’ 4 ‘ : .* * It? ite bE USOT Cer CONTENTS No.1. June 1, 1919 Tue QUANTAL PHENOMENA IN MusciE: Merrops, with FurtrHer Evi- DENCE OF THE ALL-OR-NONE PRINCIPLE FOR THE SKELETAL FIBER. Frederick H. Pratt and John P. Eisenberger.. : 1 On THE FUNCTIONAL CORRELATION OF THE HiyPoruysts 4 AND THE 5 iteeacayoy John A. Larson.. a pes rege h asia,» iy sn sae emis cle emcriycernsyas ROO STUDIES IN Scans Sein ane Beoee, I. Tar CrirRcuLaTION IN SHOCK AFTER ABDOMINAL InNguRIES. Joseph Erlanger, Robert Gesell and Herbert ISS CLITA NES a AR Nay rt ita Sar ng Rca pe Wy Ys ar 90 PROCEEDINGS OF THE AMERICAN PHYSIOLOGICAL Society. THIRTY-FIRST PAGIENTOTAST IN Ares ta TS TUNT Ghcieg setts wero scks Al dea) one checks pat aepatat cash becvawolicg Misty seotianalrcle era sie toverenoeete LG, No. 2. Jury 1, 1919 StupiEes In SeconpaRy TrRAuMATIC SHock. II. SHock Dur To MECHANICAL LIMITATION OF BLoop Fitow. Joseph Erlanger and Herbert S. Gasser.. 151 Gastric RESPONSE TO Foops. III. THe Response or THE HUMAN STOMACH To Brrr AND Brrr Propucts. Hamilton R. Fishback, Clarence A. Smith, Olaf Bergeim, Robert A. Lichtenthaeler, M artin E. Rehfuss and Philip Be OGD 3 eee ks TONES UN Nee JOO ed Fo ns Oo actee 174 GASTRIC RESPONSE TO Foops. IV. THe RESPONSE OF THE STOMACH TO PoRK AND Pork Propucts. Clarence A. Smith, Hamilton R. Fishback, Olaf Bergeim, Martin E. Rehfuss and Philip B. Hawk..............-..000005 204 Gastric RESPONSE TO Foops. V. THe RESPONSE OF THE STOMACH TO LAMB AND Lams Propucts. Hamilton R. Fishback, Clarence A. Smith, Olaf Bergerm, Martin. Es Rehfuss-and Philip’ By Hawks 002.0 0)... whales oe dive « 222 Tue EvectricaL Conpuctiviry MrtHop or DETERMINING THE RELATIVE VOLUME OF CORPUSCLES AND PLASMA (ORSERUM)IN Buoop. G.N. Stewart 233 Tue Errect or FerpiInG Pars TUBERALIS AND Pars ANTERIOR PROPRIOR oF Bovine Pirurrary GLANDS Upon THE EARLY DEVELOPMENT OF THE VVCEUTD EER ALE LO CTLELOTIN eH ap LVL GTUIULES). +t. oe nee Seca sete erat tie als hclaienele 238 Tue RELATION oF Hypopuysis TO GLYCOGENOLYSIS. Robert W. Keeton and Frank C. Becht.. Bh oa Sd Rs Me AR OE Ba coe aig hia Pep eee eee eA SS THe GastTRIC (ieee TO piaaona: “VIL. DIGESTION IN THE NORMAL HUMAN Stromacu or Eacs PREPARED IN DirrERENT Ways. Raymond J. Miller, Harry L. Fowler, Olaf Bergeim, Martin E. Rehfuss and Philip B. Hawk. . 254 STUDIES ON THE Brain Stem. I. REGULATION oF Bopy TEMPERATURE IN THE PIGEON AND ITS RELATION TO CERTAIN CEREBRAL Lesions. F. T'. Rogers 271 THE PHYSIOLOGICAL SIGNIFICANCE OF THE REACTION OF TISSUE CELLS TO Wamags Sst D mm Monte « Ee, Geese atiays yh ls AN alas ik 10 5) «smc le Sioa, byeties oun 284 iii iv CONTENTS SrupiEs ON THE NERvous CoNnTROL OF THE KiDNEY IN RELATION TO D1- URESIS AND URINARY SECRETION. I. THE Errect oF UNILATERAL EXcISION OF THE ADRENAL, SECTION OF THE SPLANCHNIC NERVE AND SECTION OF THE RENAL NERVES ON THE SECRETION OF THE KIDNEY. E. K. Marshall, Jr. and A. C. Kolls.. ; ; STUDIES ON THE Rane ous CONTROL OF THE Come IN ee arena TO De URESIS AND URINARY SECRETION. II. A CoMPaRISON OF THE CHANGES CausED By UNILATERAL SPLANCHNOTOMY WITH THOSE CAUSED By UNI- LATERAL COMPRESSION OF THE RenaL ArtTeRY. EH. K. Marshall, Jr. CUT ASO PIOUS forte 32 Ran on ee ae RNR: Shai BOA aid Sin oh en 2 SruDIES ON THE NERVOUS CONTROL OF THE KIDNEY IN RELATION TO DIURE- SIS AND URINARY SecrRETION. III. THe Errect or NIcoTINE ON THE SECRETION OF THE Two KipNeys AFTER UNILATERAL SECTION OF THE Sptancunic Nerve. L. K. Marshall, Jr. and A. C. Kolls. SrupIEs ON THE NERVOUS CONTROL OF THE KIDNEY IN RELATION TO Dre SIS AND Urinary SEcRETION. IV. UNILATERAL LIGATION OF ONE Branco OF ONE RENAL ARTERY AND UNILATERAL SPLANCHNOTOMY. Bek: Marshall, Jr:.and A. Os KeQusy cc a. wcrc. sc fein ei nies cere ais eee StrupDIEs oN THE NERVOUS CoNTROL OF THE KIDNEY IN RELATION TO DIvURE- SIS AND URINARY SECRETION. V. CHLORIDE AND SULPHATE DIURESIS AFTER UNILATERAL SpLANCHNOTOMY. JE. K. Marshall, Jr. and A. C. No. 3. Aveust 1, 1919 STUDIES IN SEconDARY TRAUMATIC SHock. III. CrrcuLatory FaILurRE DUE TO ADRENALIN. Joseph Erlanger and Herbert S. Gasser. . a ee PHYSIOLOGICAL STUDIES ON PLANARIA. I. OxYGEN ogee IN Rae LATION TO FEEDING AND Starvation. L. H. Hyman..............- Le SUSCEPTIBILITY TO Lack oF OxyGEN DurRING STARVATION IN Prank AME ICRI Seige Pa SE SSE, SIE te eee F eee 352 soe QUANTITATIVE STUDIES ON THE RATE OF eeernee Wee eer IN Puanaria. II. Toe Rate or OxyGEN CONSUMPTION DURING STARVA- TION, FEEDING, GROWTH AND REGENERATION IN RELATION TO THE METHOD OF SUSCEPTIBILITY TO PoTASSIUM CYANIDE AS A MEASURE OF Rate oF Merasoutsm. George Delwin Allen.............000cee ce eeee EXPERIMENTAL STUDIES OF THE URETER. Y. Satant...............s0000- : No. 4. SepTeMBER 1, 1919 A QUANTITATIVE STUDY OF THE EFFECTS PrRopUCED By SALTs oF Sopium, Porassium, Ruspipium AND Cauctum on Motor Nerve OF FRoaG. Esther’ Greishermer. ts. iv) ee Oe Se oO ee eee THe PRACTICABILITY OF FEEDING A SCIENTIFICALLY BALANCED RATION EN -ARMY ‘Camps: “Rt. J: ‘Anderson: |> eee AU) > eee ee AVERAGE Foop CoNSUMPTION IN THE TRAINING Camps OF THE UNITED States Army. John R. Murlin and F. M. Hildebrandt................. 302 317 326 335 339 345 ol7 403 420 474 497 531 CONTENTS V VARIATIONS IN STRENGTH AND IN THE CONSUMPTION OF Foop BY RECRUITS AnD Sreasonep Troops. Paul E. Howe, C. C. Mason and Sanford C. FOES TADR AR So < & OO ORATOR ES GIG oD BIE IE eT ap ne PRR RRL 557 Norte ON THE AcID-BasE BALANCE OF ARMy Rations. JN. R. Blatherwick.. 567 DrirepD VEGETABLES FOR ARMY Use. Samuel C. Prescott.................. 573 American Minitary Hosritat Dieraries. R. G. Hoskins................ 578 UITSTODS 5 5.5.4 SOM ARR Oil SORE ROE, Dept APNE: AE Uap 1 Zeal ea a a 589 i by a ql eS a Loree Sekt = Ny lane: fs pea ati g7 Phas ete ran, THE AMERICAN JOURNAL OF PHYSIOLOGY VOL. 49 JUNE 1, 1919 No. 1 THE QUANTAL PHENOMENA IN MUSCLE: METHODS, WITH FURTHER EVIDENCE OF THE ALL-OR-NONE PRINCIPLE FOR THE SKELETAL FIBER FREDERICK H. PRATT anp JOHN P. EISENBERGER From the Physiological Laboratory of the Medical Department, University of Buffalo Received for publication March 17, 1919 CONTENTS Part I. Methods for the graphic recording of fiber movement.............. 2 ReMMeeR PES ROC NE LOU Pcs oct cs «a tere otter so Sea atthe olein crm Spooner at cRGReTS ose 2 REPEEPETE GUTOR Cee ee ce So Lette ae oaths Onl ane SUak ates ata miheld ert 3 ihhe;mechanicalistagei. 2... OAL Sas e,. Hd eee tse SUEY 2 6 ithesmercury, mirror, and its illumination. +--+. 26 4-2 e aoe ieea seed He 9 MBE TOMY OTA Mepis he. seo5 alo ap eversisievcuar ost REO ie * «SER Eee ke 9 Mera a GE RY RR ENL GUT pay coy yh. sh 'cheysay chips sem »' 8 2 ae mS ahokes ee eco 16 Choice of plates and methods of reproduction....................-+.65- 19 Wanduct- of am Experiment: ero... ook that tcc ea eee cide os Ave fered bale 20 Parcel. Purther, evidence of a quantal principle... .....2...00ne- 3. sca. + 26 OnkihesisevOlstenms/ss; byes. ceive ce siak errata Cee ee ek Ee lee Stes 26 The twitch of fibers in response to varied intensity of stimulus......... 28 Whe determmmate character of tetanil......:-3- oscc les cs. sg cence ses le ueess 33 Miler quantce 1aCcCOn 0, PAtIPUE.;. oo, o. etee eee biek clare oe tle e Se eta 38 Quantal facilitation in the staircase effect.........)0.......00) cbc cee 38 Continuous gradients in fibral response: a contrast...............22005 42 Hiber recording as a differential method... 025 . 2 nee ge QUANTAL PHENOMENA IN SARTORIUS OF After abrupt cessation Che only evidence of fatigue is rise of threshold Break shocks, 1 per sec., rise in strength as indicated, intro- The earlier contractions fail to appear in the cut. Quantal fatigue. ducing a series of uniform twitches, which persist for a time under uniform stimuli. of contractions a rise in stimulus fails to restore response. leading to elimination of the quantal effect. RANA PIPIENS 29 EISENBERGER 1B AND JOHN PRATT FREDERICK H. 40 ez oinsy ‘paooo0d popue}xo oy} YPM poavdutod oq OF, “OE X ‘ey0} fe XK ‘JuoUTESIB[UO {OL Xx “SsBUr “LOTT ‘quiod [Bulut] ay} Sesso1d UIVSE SHNUIYS oy} SB Spue TOI ‘peonpul st ‘q 2 ‘Soyo}TA) WLOJIUN JO SOlLes B ‘sosta (Aoy oqny Aino1oUl és jod [ ‘syooys-yvorq) snynuiys oy} SV “JUBOYIUBISUI OLY OIG [BVOTZALIA OY} WOTF 9FVUTPLO OT} jo sornjavdep oy, “Sployseryy Surumudajop ur porpdde oq oF st Yor “UU [ INOqw jo 1o119 popuBy-zjo] B eq OF Puno SI atoyy ‘py jo uorysod oy} YIM aYB} pool 4So} XOq-[BUSIS “7 ‘omnqo[s Aumotowl “Y “GI-S8T61 “uve pue ‘ood ‘FZ “Sy 00S ZG uosiivdutos UQ “4Set 4B oyeyd yyIA U RANA PIPIENS 41 OF ARTORIUS INA IN NOME ) 4 QUANTAL PHE ‘UOlGoL [Bulut] Aue ul UW1dJSA (S.10u9 9} CIPpIUtopUT ou PostaAOOStp JABY pues posuvyo AJsnonurjuod pue A[MOTS 9AvY ployseryy puB SN[NUITS YO “AB 9UOU-JO-][B ay} JO UOIZBAJSUOWp SuIDUTAUOD AT[BIOedSe UB SI SIYy, ‘ondsyey peyuenb oaryvjer Aq poMO][O} Uo} 9UO JO Joao osvotieys [BJUvNb poziqryxe sey SploM IoyZO UT ssadoid oY, ‘uorpisod ysay sy 0} potoysod AT[VUY St puv ‘sast ployseryy ayy ‘seyovoridde p1od01 ay} JO pus vy} SY ‘“SedUDDSEpNdded [wIoAVS Aq 3 ‘TBF 0} SoNuTZUOD ploysecy} oY} puBLUOTPL[NUITYS JO [OAV] IOMOT B YB IBoOddvaI soyoyIMy oY} ‘GZ WOAZ ST]BJ SNPNUITyS ‘ ‘ ~ ayy SG IVY} poyoU oq [] TM I ‘stseydulo Of SUD] & Jopun OFT M UyIM Pell uv0q JABY (GEO) UTIM [BoT,UVp! a1 yore jo [8 UOTJOVIYUOD OYT, “FZ OANSY ul posozjzo] ATAVUS uolsel 04} ‘GQ QO “FZ sinsy sv oyvid owes wor yuLd youyuoD “eZ “Sly Povo ptAd te} ‘ SOAINO 42 FREDERICK H. PRATT AND JOHN P. EISENBERGER idle. This, too, would seem a priorz inevitable; for when threshold, at first elevated, subsides to stimulation level an all-or-none system must enter with full energy discharge. Continuous Gradients in Fibral Response: A Contrast Even a cursory inspection of the tracings will bring immediate con- viction that discontinuity is not the sole mode of functional change in muscle. Figure 30 is an extreme example of graded change within quantal limits. Every gap in response introduces a staircase effect; every persistent series, a continuous fatigue. Yet change of stimulus, which indeed must here be applied in order to parallel rising threshold, Fig. 26. July 25,1918; B. Break twitches, pendulum interrupter, stimuli 1 per sec. Secondary coil covered 20 mm. of primary at minimum distance (highest stimulus). The stimulus was raised slightly whenever a gap occurred in the series (rising threshold), the coil, with signal, being returned to zero position near middle of record, then raised and held as indicated. The series shows re- peated elimination of the responding quantal (quantal fatigue), with a continu- ous staircase effect after each gap. Recrudescence occurs in groups in the latter half of record. Slight contractures are present. Contact print. is impotent to alter these changes. Moreover, in spite of extreme al- teration in the individual quantal capacity, the determinate nature of every step is relatively preserved, as reference to the description of the trac‘ng will show. Thus, as expressed by Adrian (9) for the nerve fiber, the all-or-none relation between disturbance and stimulus holds good for refrac- tory as well as for normal tissue. One familiar character of fatigue, in the muscle working as a whole under frequent stimuli, is conspicuously absent in our tracings. This is contracture, so-called—the progressive elevation of the base-line asso- ciated with delayed relaxation. Long continued twitch-series at one second intervals are repeatedly obtained with horizontal bases (fig. 31). NS 4 PEPE RANA OF N) ~ ~ _ fae Bi 2 INOME PHE QUANTAL “‘{nOYSNOIY} 19Y}0SO} UOIZO" UI o1B SLOGY [BLBAOS 4SVOT YB .9O aTdiy[nur & SI poAOAul -noidsuoo st ‘syUeIpBis SNONUIZUOD JUOTOFIP OMY 4B XOQ-[BUSIS oY} JO OBUBI OIIJUD OY} GSULIOAOD TTNUITS SFL YIM “a @ jejuenb oyy, “(Z) uolyenjony jejuenb jo o[durexo uv se popivsol oq Avut ‘7 ‘SuUOT}RT[IOSO o1UBJO} OY, “Sury,Ou-10-]]e AyTSNo ( SOILS -YOUIMY o"ULL “o1njoRBij{uoo pues OSBOATCYS oonpul ‘d 'O) ‘TUBYO4 ot] SO ecg | ri I1LOS-YO IM Soon polzpul ISBIATBYS SHONnUTPUOL) 4 A ‘cp & ‘yej04 [GP X ‘azeTd WoIF YUOUOSIV[UO SOT X “SBUr “101 ‘IB[NDO UL O[PooU UOTPVAYSUOUTOP oY} JO MOpRYs oy} Aq UMBIP SUM YJ PY BSSIOSqe oy, “ATWO SoyoqIMY 10] (uorzIsod [100 ABpUODOS) SNINUIYS SoPBOIPUL PLODOT [RI SIS oy, ‘“wnynpued awies Aq JINOAITD OFOUSVUT OY} WOAF UT YNO OOM 1UBIO} JOIIq OY} .SYOOYS-YVo winjnpued Aq poonpodtd oto soyopIM} OUT, “YW JB oruTyyAYA SUIMIODI ‘SUOT}PRI[IOSO 91UBJo} OFUT A[snoouvzuods Suryvorq ‘YISUII}S UOTPR[NUTS WAOFIUN 7B poy snuvyo} SNONUTY -u0o ‘7 a fpoywoded soyoqIMy “Wf -"908 dad [ ‘1uejoq jyorq ‘q Q !*008 tod JT “soyopIMy ‘J gf S1uejoy jouq ‘g YP ‘oens1}v] pue osvolIB}S SHONUT}UOD poyxVUT UOIZIOd JoI[IVS SFT UL SULMOYS PIOVET B JO JTVY 10}}VT olf} WoL, “Ai Sle ‘9ZATNL “22°51 Rt ¥ i Tes ensonk' 44 FREDERICK H. PRATT AND JOHN P. EISENBERGER Occasional apparent exception is found, as in figure 36, C; but on the whole the fiber appears to be relatively immune to the delayed return so characteristic of batrachian muscle as a whole. The significance of this awaits solution, On the other hand, very marked contracture is frequently to be ob-. served in tetanus, if one may express by that term the relatively slow increment that succeeds the quick rise (figs. 17 and 19). . It is sometimes of long duration; sometimes merged into fatigue. Its contractural character is to be seen in the fact that if degraded by the loss of a quan- Fig. 28. Nov.1,1918;B. Large R. pipiens. Right sartorius, pelvic extremity cut. Tibial end stimulated just above tendon. Electrode pore, 7 ». Daniell cell in primary circuit. Twitches, 1 per sec. (break shocks), Bowditch clock working Hg-Hg tube-key. Contact print; first and last parts of record, 134 in- tervening contractions removed. Micr. mag., < 10. The stimuli being in the threshold region (quantal fluctuation), the succeed- ing continuous rise and fall of stimulus introduce quantal gradients, with an ap- parent continuous fatigue at A (ef. fig. 29). The twitches fail abruptiy (apparent quantal fatigue) just before B, and are restored by again raising the stimulus, which brings in another continuous decrement at B. Subsequently, for the re- mainder of the record, a slow continuous fatigue is seen in the quantal main- tained by the maximum stimulus, with occasional spontaneous reversion to the minimal contaction which is seen likewise to have shared in the fatigue. tal (figs. 16 and 32) the amount of the increment tends to be assumed for the time being by the next lower step or, if the degradation be com- plete, by the base-line. Figure 15 is notable from the virtual absence of such increment. Fiber Recording as a Differential Method The reward of reduction to components in any complex system is a new instrument of analysis. One of us (3) has shown how, by the induc- tion of fatigue in a multi-quantal system, the successive elimination of elements will reveal finally one, and one only, whose threshold still lies QUANTAL PHENOMENA IN SARTORIUS OF RANA PIPIENS 45 4 b2 ene ~ 8, X 34; total x 33+; with corresponding lettering ) Portion of figure 5: = lr) N 5 FREDERICK H. PRATT AND JOHN P. EISENBERGER ‘PlOysely} BUISIA oy} 0F po}VpPOUTUIODNT SUM plover oy} SULINP SN[NUTYS JO yysuelys oy, ‘dq Ul survoddvod ‘uledys [Boye] WoIy ‘Y JO pudt} pAVA ov oIsLoyoraeyo oy} “Z “gq YB qYStoy [BUISILO oY} O}F [eyuBnb oy} Jo 2 4B AdoAOooI Ol} ‘7 st ‘ApoATzoodsou ‘ff pus CG YM g puvs Vy Aytpuopt 07 Surpuio} oouplAd Joy PANT ( puodes oY} Wor opVUT YSoq ST JUSULINSB ‘payenyusoon uooq svy (7 ysay oy} JO FtuUITs oy) ‘quoUoInsvoUL [LN Aq poymoa Apjuetndde sureq uorjduinsse otf} a—p=q-—0 dq [[IM pojsossns oAOGE UOTZBIOL OU} ‘ATOAT} -osadsou ‘a pur p Aq py puew ( jo sorjrjuRenb oy} Surpous(dy ‘on31yeyj Aq poysruruup gq JUENzIySUo) oY} ATuo YIM ynq fy Jo vou -sopnidot GB dUTEq JO poyoodsns oq Avul (7 ‘7 [ejuenb popeisop oy} syuesoidea ATTenjow W JT “FUEN}TYSUO OU yuaplAod st J yorys jo TejuBNb Joysry B St YOrM ‘y jo yey} “o pus ‘g “uo1}OB1} U0 JUBUTUTOP ayy jo AyrQUVNb oy} yuosoddod g Jo] :SMOT[OJ SB poZIUsOdoI oq OF SI poadosoid o1v S1oQOBIVY equenb yey, “suoryRpnpun MOT OF Aouopuo} JUonbosqns v YIM ‘oNs1yBy PUB asvodieys sronUTzUOS [BOIdAZ SMOYS 4 {ouT] plodod MoU B LOJ Surysn(pe pues ojvpd oy} SuruANJor OF JUOpLOUL Fort JO pottod 4toys oy} OF onp yooyya ATOAODOL B ST) dnoas oy} ‘g Solos Ul SNUT, ‘ded oy} JO YISUS] OY} YIM SOBA YOIYM JO FUO}XO ayy ‘ALoAODIL Aavaoduio} & 07 SpBo] ‘taAoMoy ‘dvd AdoAKT “GE Solos JO SUOTJIVAPUOD JALOYS OF Aq Aypeuy poyuosordod st Yours ‘noysnosyy g [eyuenb jo Juotodo90p dAIssoIBoId PENJUGBAD UB SMOYS PLOOOL OLT}UO ay} jo Apnjg ‘“poytvur ALA SI onS1yey SNONUTZUO!) ‘poonpoadot st ATWO PLO990 JO qgavd ysatqy “GG X “[B}0}.- GE X posavpue {OT X “Sv “Tory, “oTpoou UOT} BIYSUOW IP jo Mopvys oy} Aq UMBIP VSSIOSqE UB ST puvq Vp JOMO] OY], “UOISsooons oVIPoUMUUT UT UAB} OLOM PUL ‘yowa SUOTPIBAY -U09 QOP JNOGV JO ySISUOD g PUB | “7 Sollos OL, ‘winjnpuod Aq ‘das sod J ‘syooys-yworg “Sruruopd’s snjoot JO uLsieuL WOT] WU Z O[NGO[S Surploood !SpAry} o[pprur puw [VIqry Jo uoryouNt 4B OpOdpOOTO + SNIMOPAVS JOVPUT ‘y {S161 ‘ZI ‘SnV “0¢ “Sl ommeenetsy ee S| jh dee ii 47 NS RANA PIPIE OF ) SARTORIU INA IN NOME 7 4 PHE QUANTAL ‘WW UO oy} Ul SUOTJOBIYUOD I uorTyoOn psp o"U“LL “ONSI} BI jeyuenb jo }[Nsed ayy SB peel} Uso Yip [eulrUuTuat MoU [BI9AVS JY} JO JUSTIOINSBOUT Aq pojioddns s ayy w pur ‘(q ‘9 ‘g ‘V) [BulluTUL plo 944 p “(y “) Ayyuenb [VuIxvUqns 9y} SUIEq a fw = p — a ‘uo1yenba oy} Aq posseidxa eq Avu sty, ‘ouoye sivoddy Mou yo puBw Y UT 1OJOVF [BUOT}IPpe oY} VY} puB ‘peyeuruntja AToJoTdur09 4ST 4B st ‘oIn]ey Suo] ‘q-V Settes oy} Sursoduioo [eyuenb ysiy oy} yeVyy juoivdde st 4] “[BUIIUIUT AOU oY} JO Seltos UaAD puR sivodde urese yequenb punoduioo ‘ieysiy oy} Y FY “[BUILUTUT Mou ® SI esuodsel oy4 JO SUSIS cUIMOY ajoTdu100 & 07 ad"Td SOATS BDUO 4B YNq - puv {0} pepuodser ore syaoys oyvusoye ATWO YOY Y Woy “_ ‘WOTJOVAZUOD OY} SB }1 0} pepp’ puB “ToqY Iodvep 10 SUTAT -jno uv Surjuosoided ‘7 ye poyowod st [eyuBNb Mou B AT[VULY “APIATJOV UTRJOI OF LopO UT SNINUIL}S JO oSvoIOUL BY} ONUTPUOD O} Aaessadeu sawooeq 41 Ajyuenbesqng ‘q 4B JI SoLO}Sod SNINUIT}S SUIST [JUN pozVUrUTIfo ST [BJUBNb oy} pueB “oATJoIo Igsuoy ou Be ‘INUIS wWaAosuN fasvodieys pedojeasp ATMOTS B O}UT Surs1oUr ‘91N}OBI}UOD n[nurys oy} Y FV ‘“PAIND AIMOT UI pozPvoIpUr S YSIS YIM onByvy Arojonposjyur ‘g p “40S 9y} Jo pus oyy Aq UMBIp SI Ploy YABp sy} Jo espa oy} Aq PoUlIOT BSSTOSqB of], ‘ce & ‘Te}0} foe & “pasivpue {OT &X “SvuI oly *10}dnd10j UT umynpued Aq “des Jad | aAG {Ssn11ojie I6E ‘92 ADL “1S “SI ‘syooys-yvoiq [BUIIUTT, ‘“aporjooyo 7 y fsorieppidvo [eroytodns ur s[qIsIA UOT}B[NOITO - ISENBERGER 4 E 1 AND JOHN PRATT H. DERICK u Lol tT [ow ey oyeulupo ALdnaqe | JJOS}t St “ATTRUY ‘SIP} !poyeryuodoyrp yASuo] yw st (O1luvyjoy MOU) [BUTUTUT oUTES oyL ‘peyuenb yeunxvurqns oy} yuosotdod A]JUOptAD SNUvIO} SNONUIZUOD OY} JO JoAST UMUTLXBU oy PUB snUyo} joltq oY], “puo 4B Solos oY} Setoysoi AT[eryaed Ayuo ili SNINUTYS JO oSvolouyT *(pjoysoety} JO osi1) onsiyey [wyuvnb Aq yno syjVy YRsuo] 4B Yoga ‘jwuTurur Aq poows;dot A[YUOUvUUIOd Y}sue] YB puv “OF SuIZLOAOAT on][VA [BUITXBUIqNS oy} ‘onSIyvy SnonuIyUo0D ALOJONPOLZUL UB SMOYS SOYO}IM} JO Solos oY, ‘GEL X “seul “101 ‘juitd Jowyuory *(ojousvUL) oAaNO ONSIVBVy OUBJO} SNONUI}ZUOD AQ PoAOT[OJ ‘snuv}o} Jortq ‘pusa yy ‘oouBYsISOL ATBUITId SUI -Svoloop “utut QT poddorp sv sroprys ptooooya uoyM “puo Ivou dvs Suoy 07 dn Ayisuoqut UL VSUBYD 9JBIOqITop OU !UOT}RNUITT}S opnty ‘aos Z dod |] ‘syooy yvorq UN[Npuoeg ‘“s[ivjop [evj}uetdedxe IofJ Z] eansy Jo puosa] 00g ‘Vy {RT6T ‘ge ounr ‘ze ‘OI ve eeneneanaalliy QUANTAL PHENOMENA IN SARTORIUS OF RANA PIPIENS 49 Fig. 33. July 18, 1918; A. Latent period. Sartorius; pelvic attachment cut superficially; capillary circulation active. Electrode (7 uw) at tibial end; record near pelvic end; 5 exposures; 4 minimal contractions, | submaximal. The time curves (tuning fork moving signal diaphragm, 512 d.v. per sec.) correspond in as- cending order with the contraction curves (make-twitches). The first summit denotes stoppage of optical signal by Pt-Pt primary make-contact. The stimu- lus was not altered except for the upper and last contraction (submaximal). Contact print; micr. mag., X 10. Fig. 34. July 19,1918: D. Latent period. The description of figure 33 applies to this, except that the stimulus was increased in ascending progression. At least three different quantal values are registered. THE AMERICAN JOURNAL OF PHYSIOLOGY, VOL. 49, NO. l 50 FREDERICK H. PRATT AND JOHN P, EISENBERGER beneath the level of stimulation. Such a process is now shown graph- ically in figures 31 and 32, where it will be seen that the process is by no means dependent upon fatigue of a continuous character. The re- mainder in such a series may or may not be the contraction of a single fiber. If irreducible, except by extinction, it is probably, in accordance with the first postulate on page 6, of either single or double quantal constitution. That every quantal is a law to itself is clearly shown when fibers long in activity are compounded in action with others brought in by change of stimulus or threshold. The effect is a resultant which, in accordance with the dominance of one or the other, may exhibit stair- case, fatigue or a virtual level. The chief example of this is seen in figure 37, which will presently demand special consideration. The Latent Period Reference to figures 33 to 35, included largely for the method, will show that there is here opened a fruitful field of enquiry. Biedermann (10), in his discussion of the latent period, reflects the generally ac- cepted view that the period is, within the submaximal range, an inverse function of the stimulus intensity (Tigerstedt). The fact, however, which he also points out, that varying maximal stimuli do not control the length of the period (Helmholtz, Tigerstedt), introduces an inter- esting problem. It will be seen that no evidence is forthcoming from our results pointing to graded latent periods for a given quantal. It will also be seen that far greater refinement is necessary to make them of more than negative value. If the actual excitation process be of sufficient duration to contribute to the period as a measurable quantity, the all-or-none character of the response concomitant must have the simplifying value of a constant and hence negligible factor in the problem. Muscle Phenomena, Real and Virtual The object of this paper has been primarily to introduce the details of anew method; and secondarily to furnish as firm a basis as possible for | an application to future probems of a conception of muscle activity which renders the gross phenomena, so long studied, necessarily subject to a certain amount of re-interpretation. Such re-interpretation, we believe, must take cognizance of two very distinct modes of altering mechanical effect. To what extent are gross muscular gradations to be a1 NS — ) uu QUANTAL PHENOMENA IN SARTORIUS OF RANA PIPIE ‘popiodel pUB UMOUY SB IBJ OS posuBYOUN SUIUIBUAI SdIIoS ay} JO UOT}I0d SI} IO} tNuys 944 ‘(Ze “Sy “Jo) snoouvqyuods AyJuoIvdde ‘sindd00 Jaa [VIJUdIOYIp o[qeyIvulel B& G-Pp JY ‘Salles sv]ppru oy} Ul YQ 9B ydodxo sdUApIAG UI o[}4I] SI oAMJORAJUOD ‘*(eNSIVV] puUB sSBOITeYS) JUSSeId oI S}UBIPBIS SNONUIyUOD poyITiy ‘OL X “seul ‘dorur {quid yovjU0D =‘“papsoded SNTNUITIS WNUITXBUI 9Y} YJIM SumMurjuo. sotles Joddn ayy ‘salloS UOIJOVIJUOD JAMO] OMY oY} 09 A[dde puv ‘snonuTjzUOD a1B UOTJISOd [100 AIepUOIS JO Sp1OIII OM} OYT, “ANOY uBR uBYyy a10W JO poliod SuIp1oved poulquiod B IdAO 9}R]d SITY} UO po9dBIy oIB (‘das Jed | ‘syooys Yeoiq WN[Npued) seyo}1A4 QOOF ATo}vU -1xoiddy ‘puo orajod avou paooad fajosnur Jo a[pprur qnoqge (7 7) eporjooy “AIvUOTyeIS UOIYTNaId Areyideo {uoieiedoad Jo uole]duiod Jojje SINOY E UdYB} pALODVY ‘SoTjTUIaIjxo9 YJOG Ye podoaAos A[doep ‘snTIOJIVG “VW SRI6L ‘OT “3dag “9g “SIq "SUOT}OBIZUOD BY} JO wistuoIyoUAS ay} JQnop UI SUIABIT, SNYyy ‘aziUOIyOUAS 0} ATJOVKXO [BVUDIS [Bvo1IVdO JYy JO aN] Ivy oY} AG VOUOPIAD SB POAT}RGOU SI qooye suoU-10-[[B JuoIvddeoyy, ‘“asUBI [BUTTIUTUI UTYyIM ydoay ynq ‘asuodsed YORI LOJ PoSBVaIOUL SEM SN[NUITJS vy J, “poploovet auo 4say oy} 0} SurAydde oAano-ouriy ayy ‘posodurtdiodns suotovs}uod [VUITUTUT XIQ) “FE aINSY ur se uolyeredoid oures oy, “GE Sly] essnamaeemem tnt en me et a i$ RIT gE [ea *JUOTPBAS ONGIYBY JO AyinuTyUOS YAAK yNq ‘days puooes oY} OF UINjod ydnaiqy ‘royorreyo peyuenb yo Ayquqoad ‘suorenjony [VIFLUT T ‘jequBNb JUBUILLOP OY} JO ONGT}LF SNONUTZUOS SMOYS sSMO][OJ Sv o1B SJUDAD joryo out _ 01 V WO oAos uodn Yovolouo O04 quenjyony AT} UOTO UN > OLB Tynurys oyy So1los TOMO] ony uy 4x0} OY} UL POSsNosip SI plod ST} JO OOUBOYLUSIS [VIJULOTIP OUT, ‘yeqyurnb yueuruop Jo quoIpRas onsrywy Jo uorydunsoy *¢ ‘ONGIyVy OFUL SUIGIOU SVIATBYS [VIYLUL YIM ‘equenb pay} Vy “€ ‘{UOUOAOUL OSTVOIIVIS BULOSLOPUN jejyuenb Joysiy Vy * {jE ‘yeyuBnb yuvulwop jo onsiyey snonurjuUol) *T sortos Joddn oy, “Sploysetyy peyuenb ‘g—y ‘Qe oANnSY JO Solos VoATl ol oO UOT iod posaeyuyy “Le “SIy a-V 9 or f {1} OY} J t} I [Ua 26 “oi f 14 G QUANTAL PHENOMENA IN SARTORIUS OF RANA PIPIENS 53 interpreted in terms of continuity; to what extent in terms of discon- tinuity? Until these precincts, which certainly appear to overlap where the tissue is studied in the gross, can be defined it is unsafe to reason from molar to molecular events. Even staircase and fatigue effects, as already shown, may be described in strictly quantal terms. These may further be superimposed on con- tinuous gradients in such a way that only extreme reduction to terms can separate the two distinct types of response. The tracing A, B in figures 36 and 37 emphasizes this very sharply. The series taken to- gether is a staircase, merging into a fatigue. But it is quantally com- posed; each quantal having apparently its own state of irritability and contractility. Analysis shows that the whole is subject to the slow degradation of a dominant quantal reflecting long continued activity, carrying the others as they appear. But its dominance is utterly ob- scured temporarily by the idiosyncrasies of the less fatigued elements, which manifest their own gradients quite’ independently. A muscle capable of differential activity of this sort would indeed prove deceptive toward any attempted description. Apparently the sufficiently complex web of muscular behav-or must be approached on wholly new lines of analysis, directed toward the dis- entanglement of the actual from the seemingly continuous processes. It is not to be wondered, therefore, that so many phases of muscular function, though elicited with ease, have remained in their essence obscure and baffling. Such problems need restatement to yield new points of attack. SUMMARY A complete account is given of the method for photographically recording the contraction of muscle fibers on excitation with the pore- electrode. By the use of the apparatus an experimenter is enabled to watch through a demonstration ocular the movements of the record- ing mercury-globule mirror on the surface of the muscle, while these are being automatically recorded, and at the same time register on the plate, by turning a lever, the actual extent of movement of a secondary coil. Thus the continuity of stimulus variation is shown in a curve codrdinate with that which reveals the quantal or discon- tinuous character of contraction gradients. Full details of principles and construction are shown in the drawings, and a number of graphic records are reproduced, illustrating the differ- ent phases and capabilities of the method. 54 FREDERICK H. PRATT AND JOHN P. EISENBERGER On these records further and more complete evidence is based with respect to the all-or-none behavior of the skeletal muscle cell in simple contraction, tetanus, and staircase and fatigue effects; and the sig- nificance of latent periods as obtained by the method is briefly discussed. Emphasis is laid on the opportunity for analysis of mechanical ef- fects which the method furnishes, since the continuous gradients can thereby be readily differentiated from the discontinuous—functions which must always tend to confusion or obscurity in gross muscular action. | BIBLIOGRAPHY (1) Lucas: Journ. Physiol., 1909, xxxviii, 113. (2) Pratt: This Journal, 1917, xliv, 517. (3) ErsENBERGER: This Journal, 1917, xlv, 44. (4) Pratt: This Journal, 1917, xliii, 159. (5) RayLetcH: Nature, 1901, Ixiv, 385. (6) Prxir: Annal. de Chimie, 1832, 1, 322. (7) BrepERMANN: Electro-Physiology (Transl.), London, 1896, 1, 69. (8) Lucas: Journ. Physiol., 1905, xxxiii, 137. (9) Aprran: Journ. Physiol., 1913, xlvi, 412. (10) BreperMANN: Electro-Physiology (Transl.), London, 1896, i, 72-73. ON THE FUNCTIONAL CORRELATION OF THE HYPOPHYSIS AND THE THYROID JOHN A. LARSON From the Rudolph Spreckels Physiological Laboratory of the University of California Received for publication April 4, 1919 INTRODUCTION Workers have for a long time noted certain resemblances in structure between the hypophysis and the thyroid gland. Thus there is a sub- stance present in the pituitary which resembles the colloid material in the thyroid. Again in addition to marked similarities of function in relation to metabolic processes these two endocrine glands play an al- most identical rdle in respect to growth. The extirpation of either gland slows or checks developmental processes in general, and especially inter- feres with the functions of the sexual organs and the nervous system. If the extirpation of one gland causes changes in the structure and function of the other, there is ground for suspecting that there exists normally a functional reciprocity between the two. For instance, if the hypophysis should undergo hypertrophy as a result of thyroidec- tomy a natural inference would be that the pituitary had taken over some part, if not all, of the functions of the thyroid. Such an inference would be strengthened if one gland could be substituted for the other. The literature upon the results of hypophysectomy is very meager owing to the inaccessibility of the gland and the difficulties encountered in its removal. Smith (57) and Allen (1) working independently, found that hy- pophysectomy in frog embryos produced changes in the thyroid. The glands in most cases were only about one-third as large as those of the controls and showed atrophic conditions histologically. Pardi (39) experimented to determine whether modifications of the structure of the thyroid could be caused by pituitary extracts or by other extracts, spleen and liver, as well. He found changes of structure which indicated colloid hypersecretion but that practically the same alterations followed the injection of the various extracts. 55 56 JOHN A. LARSON Cushing (15) reports in six dogs a hypertrophy of the thyroid after hypophysectomy. Blair Bell (6) states that after extirpation of the pituitary One anticipated finding hyperplasia in the thyroid, for Cushing is very definite on this point, but in no case was any change to be discovered. While after complete removal of the anterior lobe no changes could be seen, he found in one dog following partial extirpation of the anterior lobe that the thyroid was enlarged but normal histologically. Hous- say (28), in the dog, reports an excessive accumulation of colloid and sometimes degeneration of the cells in the thyroid following the removal of the hypophysis. Aschner (3) found that the extirpation of the pituitary in young animals causes increase of colloid in the thyroid. From the above results it is apparent that hypophysectomy causes marked changes in the structure and appearance of the thyroid. On the other hand the effects of thyroidectomy upon the pituitary are even more pronounced. Rogowitsch (49), in 1886, found enlargement of the pituitary fol- lowing thyroidectomy in rabbits and dogs. He also reported an in- creased production of colloid by the cells of the anterior lobe with indi- cation of its passage into the blood vessels. In rabbits he found a doubling of the weight of the hypophysis. He was induced by these re- sults to formulate the theory that after thyroidectomy the pituitary takes over the function of the thyroid gland, and as a result of its in- creased activity endeavors to compensate for the loss of the thyroid secretion. In the herbivora where there is but little apparent effect of thyroidectomy the pituitary is large and the compensation is sufficient to meet the requirements, but in the carnivora the pituitary is small and the animal dies as a result of thyroid deficiency. Later the discovery of the true relationship of the parathyroids to the thyroid accounted for the different symptoms exhibited by the herbivora and carnivora. How- ever, now, evidence began to accumulate substantiating the results of Rogowitsch. Hofmeister (26) found hypertrophy of the hypophysis in thyroidec- tomized rabbits, the gland having nearly doubled its weight in the course of twelve weeks. Stieda (59) described hypertrophy of the anterior lobe brought about by an increase in the number of ‘‘ Hauptzellen,” with the formation of vacuoles in them. He was unable to find any changes in the cromophil cells or formation of colloids. Degener (16) found the pituitary to be three times the normal size in the rabbit one FUNCTIONAL CORRELATION OF HYPOPHYSIS AND THYROID ot hundred and seventy-nine days after thyroidectomy. Simpson and Hunter (56) found an increase in weight of 15 per cent in lambs and 20 per cent in the adult sheep after thyroidectomy. Gley (21) reported the normal weight of the pituitary in the rabbit as 0.02 gram. This in- creased to 0.10 gram at the end of a year (five times the normal), after thyroidectomy. Leonhardt (34) found an increase of one-half in the hypophysis of the rabbit after one hundred and twenty-six days. Lucien and Parisot (36) always found an increase in the weight of the hypophysis in the rabbit. Cimoroni (12), in the dog and rabbit, found a distinction between the nature of the hypertrophy of the pituitary which resulted from castration and from thyroidectomy. Torri (61), in the same animals, reported similar changes. Parhon and Galstein (40) always found a hypertrophy. Traina (62) found little or no in- crease after fifteen days. Hoskins (27), in his experiments upon am- phibia, found what he designates physiological hypertrophy of the an- terior lobe of the pituitary after thyroidectomy. This explains the gigantism and infantilism noted in the thyroidless larvae. The failure to metamorphose was due either to the loss of the thyroid or to the ab- normal secretion of the anterior lobe. The hypophysis of the female was larger than that of the male. This might account for the fact that the ovary differentiates earlier than the testes. Rogers (48) re- ports an enlargement of the anterior lobe in Rana pipiens following thyroidectomy. Alquier (2) saw in the dog an increase in volume and signs of hyperactivity. Kamo (30) reported a hypertrophy of the hypophysis in puppies one and a half to five months after thyroid- ectomy, the pituitary being enlarged to two to five times the normal size. The chief change was in the anterior lobe. An enlargement was also noted in the adult dogs after operation. He also reported that parathyroidectomy caused no changes in the anterior lobe, but an in- crease in volume of the pars intermedia in puppies and an augmented deposit of colloidal substance in the adult animals. Thaon (60) per- ceived hypertrophy and structural changes in the young ram after forty days. Trautmann (63) studied the effects of thyroidectomy in goats and reported a hypertrophy of the pituitary. In a histological examination he detected vacuolized areas and other evidences of what he considered to be degenerative changes. Therefore the hypertrophy may be of a pathological nature and not indicative of physiological activity. Klebs (32) found hyaline globules in the blood vessels of the nervous part of the pituitary, struma-priva dogs, and therefore assigned the origin of the disturbance to this organ. 58 JOHN A, LARSON Boyce and Beadles (9), in cases of myxedema, reported an enlarge- ment of the pituitary and an increase of colloid in the posterior part of the anterior lobe. Large cysts filled with colloid were seen here. The posterior lobe was atrophied. Herring (25) worked with cats, dogs and rabbits. The changes were most marked in the rabbit. He found that the anterior lobe was ap- parently unaffected but that there was increased activity of the cells of the pars intermedia and a probable increase in the number of these in animals surviving the operation for a considerable period. He noted that the changes were most marked in the nervous portion of the pos- terior lobe and in the laminae constituting the floor of the third ven- tricle. Here colloidal bodies of a hyaline or granular nature were very numerous. There were also localized proliferations of neuroglia. Ac- cording to Herring, the extensive production of colloid was merely an exaggeration of a normal process. Degener (16) found that the hypertrophy affected all parts but most of all the pars anterior in which sometimes colloid vesicles develop simi- lar to those of the thyroid. Halpenny and Thompson (24) desertbed enlargement of the pituitary with an increase of the colloid vesicles in the pars intermedia. Kojima (33) reported that in an animal killed thirty-four days after thyroidectomy the pars anterior was less compact in structure than in the normal rat, and a larger number of vesicles were visible over the whole section. These vesicles varied in size and shape. Many were filled with a hyaline substance, which stained faintly red with eosine; others were empty; there were also a number of large, swollen-looking cells, the cytoplasm of which was opened in appear- ance. Numerous small vacuoles were noticed. The ordinary oxyphil and basiphil cells are remarkably few in number. The pars intermedia was relatively thickened. These changes were already visible twenty- three days after thyroidectomy and they were not removed after feed- ing the animals for some days with one gram of ox-thyroid per rat per diem. A. E. Livingston (35) found that thyroid feeding prevented the in- crease in the size of the pituitary which would. otherwise be caused by thyroidectomy. Thus, to recapitulate, practically all investigators agree that the pi- tuitary increases in size as a result of thyroidectomy and that the gland contains an increased amount of colloid material. Opinion, however, differs as to where in the gland this colloid isfound. According to Simp- son and Hunter, the pituitary colloid is not identical with that of the thyroid and contains no iodine or but slight traces. FUNCTIONAL CORRELATION OF HYPOPHYSIS AND THYROID 59 On the clinical side there is also evidence of disturbances in the hy- pophysis as a result of thyroidectomy. Niépce (87), in five cretins, found all the pituitaries to be enlarged. Pisenti and Viola (43) found much colloidal substance in the pituitary in cases where the thyroid was the seat of a fibrous struma. Dolega (18) reported that in a cre- tinoid skull the pituitary fossa was relatively larger than in the normal skull. Boyce and Beadles (9), observed hypertrophy of the gland in cases of myxedema, with increase of colloid in the posterior part of the anterior lobe, a doubling of weight. Schénemann (54), from the study of the pituitary and thyroid glands of one hundred and twelve cases in Kocher’s clinic, found support for the hypothesis of Rogowitsch. Comte (13), in one hundred and eight cases of thyroid disease, found a hypertrophy of the hypophysis when the thyroid showed atrophic changes. Calderara (10) reported the same in a case of myxedema and the presence of much colloid in the pituitary. Bourneville and Bricon (8) found enlargement of the pituitary in cretins. Eichorst (19) found in cretins and cases of myxedema a hyperfunction of the pituitary. The gland was larger and hyperemic. There were often hemorrhages and later a growth of connective tissue and cyst formation. Finally the pituitary became smaller and smaller. Wells (64), in a case of scleroderma where the thyroid was greatly atrophied, found the hy- pophysis to be twice the normal size and this increase seemed to be due to the large accumulation of colloid material. On the other hand, in some cases, no change in structure could be detected and in a few cases the pituitary was below normal. Coulon (14), in five cretins, found the pituitary to be normal or below the aver- age size. Ponfick (45), in a case of myxedema, found a degeneration of the pituitary. Thus the preponderance of clinical evidence points to hypertrophy of the hypophysis as a result of thyroid deficiency. Simpson and Hunter (56) experimented on the assumption that the iodine-containing body in the thyroid represents the active principle or internal secretion of the gland. Therefore if there were a compensa- tory activity on the part of the pituitary as a result of thyroidectomy they expected to find some iodine. The failure to detect iodine is con- sidered as evidence against the theory. They found in the sheep that removal of the thyroid does not lead to the appearance of iodine in the pituitary and that therefore there is no vicarious relationship between the two glands. Their assumption is based on the statements of Bau- mann (5), Halliburton, Candler and Sikes (23), that there is no iodine 60 JOHN A. LARSON in the human pituitary. On the other hand Schnitzler (53) did find positive evidence of iodine in the human pituitary but in very small amount. He therefore assumed that the iodine is present as iodothyrin and brings forward his result in support of the view that the thyroid and pituitary may act vicariously. Wells (64) also found a small amount of iodine in the human pituitary. As compared with the thy- roid the proportion was about 1:50. Pellegrini (41) studied the rela- tion of the thyroid iodine to pituitary functioning. According to the abstract (the original was not accessible to me),— No relation was discovered between the volume of the hypophysis and the amount of thyroid iodin. The same is true as regards microscopic evidence of functional activity, relative size of the lobes of the hypophysis or frequency of occurrence of the various cellular elements. There was noted a marked lack of pigment in the neural lobe in cases in which the iodin was decreased. The failure of Simpson and Hunter to detect iodine in the pituitary after thyroidectomy does not necessarily invalidate the idea of a func- tional correlation. The autacoid supplied by the hypophysis although perhaps not containing iodine may be able partially or wholly to take the place of the thyroid hormone. In addition to the experimental data it may be mentioned that con- siderable clinical evidence exists of the correlations between the two glands. Thus Falta (20, p. 323) calls attention to the fact that after extirpation of a part of an adenoma in a case of acromegaly, there was an enlargement of the thyroid. Again, Benda (7) is quoted as saying that in Basedow’s disease the glandular hypophysis is small. Josefson (29) reported associated hyperplasia of the hypophysis in a case of congenital struma of the thyroid. It is interesting to note that pathological processes may occur spon- taneously in the two ductless glands. To illustrate, Rosenhaupt (50) reported a case of sarcoma of the anterior lobe of the hypophysis, in which there was also a tumor of the same nature in the thyroid gland. Again indications of hyperthyrosis may occur with corresponding pathologico-anatomical alterations of the thyroid gland. In multiple ductless glandular sclerosis the sclerotic process usually affects the hy- pophysis and the thyroid. A slight degree of thyroid gland insufficiency may occur in hypophyseal dystrophy. Iso the hypophysis may de- generate in the later stages of Basedow’s disease. Again Falta (20) states FUNCTIONAL CORRELATION OF HYPOPHYSIS AND THYROID 61 The pathologico-anatomical finding in the thyroid gland in acromegaly almost always shows something abnormal. When hyperthyrosis has existed, there is found the picture of a Basedow’s struma. Otherwise there is seen almost always connective tissue proliferation, such as is found alsoin other organs in acromeg- aly, or colloid degeneration in combination with, eventually, high-grade scleros- ing and atrophy of the parenchyma. Gaussel found a thyroid gland that was normal. Thus a summary of the literature clearly establishes the fact that the removal of either the hypophysis or the thyroid gland causes definite changes in the structure of the other. In the case of thyroidectomy the consensus of opinion is that the hy- pophysis undergoes hypertrophy. As to which portion enlarges the most, the anterior lobe is indicated wherever a specific region is men- tioned. In making any statement, however, regarding hypertrophy of the pituitary, the extreme variations normally occurring in animals of the same species and of the same size must be taken into consideration. For instance, some of the glands of the ox often exhibit two or three times the proportions found in others. This fluctuation merely emphasizes the necessity for accurately controlled investigation. Hypertrophy of the hypophysis following thyroidectomy has by many investigators been considered evidence of a vicarious relationship be- tween the two glands. Assuming that the hypertrophy of the hypoph- ysis is physiological, the next question to arise is that of the extent to which the pituitary can function for the thyroid. That the sub- stitution, if it exists, is ncomplete may be shown by the myxedematous symptoms and often the death of the animal following thyroidectomy. Since the compensatory effort on the part of the pituitary substance attempting to perform a double function in the absence of the thyroid is insufficient, the administration of hypophyseal extract should prove beneficial. Through the adjuvant action of the added hormone the pituitary might now perform its double task. THE EFFECT OF ADMINISTRATION OF THE ANTERIOR LOBE OF THE HYPOPHYSIS TO THYROIDECTOMIZED RATS In order to ascertain the effects of direct administration of the an- terior lobe to thyroidectomized animals it was essential to find a species in which the injurious effects of parathyroidectomy were at a minimum. It is usually impossible to extirpate the thyroids completely without injury to the parathyroids. 62 JOHN A. LARSON The rat was finally chosen, as this animal is particularly favorable for these experiments and is not subject to tetany as an early result of removal of the parathyroid. The only apparent modifying factor is that of age. I have found that rats weighing less than forty grams in- variably die as the result of operation, convulsions being observed in some cases. The rats selected were approximately of the same size, age and strain, and wherever possible, from the same litter. The importance of these details in the selection of controls cannot be over-estimated. Growth curves of normals obtained in one can not properly be compared with those of experimental animals at another season. The thyroids and parathyroids were completely removed under ether anesthesia. After some preliminary operation work to ascertain the simplest technique and the most favorable age, the rats were divided into four groups. Two series were operated and fed fresh liver and anterior lobe of the ox respectively in addition to the normal diet. Two other groups were control animals and fed liver and anterior lobe; the amount of liver administered corresponded to the quantity of hypophysis substance. The rats were all kept in individual cages in order to insure a uniform consumption of the glandular food. An excess of food was furnished so that the rats had access to as much as desired. The ordinary diet con- sisted of swill, barley, cooked rice and fresh cabbage, but no water as the animals seemed to thrive best without it. Besides the special glandular materials, a small quantity of salt was kept in each cage. As for the ‘ dosage of anterior lobe administered, the average amount during the first three months varied from one-half to one gland per rat, and later, two to three glands administered at least three times a week and more frequently when the glands could be obtained. But in every case the same amount was fed to each rat of the two series. The dosage used is larger than that usually reported as allowance was made for a de- struction of some of the active principle in its passage through the ali- mentary tract before absorption. In an attempt to determine the maximum amount of glandular sub- stance utilized, all of the excess of glands after each feeding was admin- istered to two individuals, one in each of the pituitary groups. The number of glands varied from two to eighteen per rat, but each received the same amount. In comparison with their respective groups the op- erated rat thrived best, the normal individual losing weight, but no more than a rat fed the ordinary amount. These results seemed to FUNCTIONAL CORRELATION OF HYPOPHYSIS AND THYROID 63 indicate that the organism is capable of utilizing only a certain amount of the pituitary autacoids, and that an excess is eliminated without any deleterious effects. The hypophyseal substance was given to the animal in a separate dish and from the outset the rats exhibited a marked predilection for the anterior lobes, eating with great avidity all that was administered. After two or three feedings the animals would snatch the glands out of the dishes in preference to any other food. In fact the glands were consumed with greater eagerness than the liver in the other groups. The rats were weighed each week and their general condition noted. When an animal died a careful search was made for thyroid tissue. Any rats dying less than two weeks after the operation or from known accidental causes were discarded. The experiment proper commenced June 3, 1918, and terminated February 3, 1919. The remaining rats were killed and prepared for subsequent examination. The entire group of rats, seventy in number, was subdivided into the four series. The subsequent history of each rat was recorded in tabular form, the data being secured from the record of weekly weighings and curves plotted from the same. Two distinct sets of tables were drawn up, the first of which, tables 1 to 4, commence the experiment with the initial weighing of each rat. The chief value of the results presented herein is to indicate the conditions of growth before operation. It was found that thyroidectomy caused but slight immediate effect; in some cases a loss of a few grams was noted at the time of the next weighing. In the second set, tables 5 to 14, the same data are used but the com- parisons begin with the date of operation. The results stated in this form are seen to emphasize the relations observed in the first set of pro- tocols. Upon comparing the two sets the chief difference is to be found in the figures which are based on the weight changes, although the rela- tive proportions of the different groups remain unchanged. Since the date of operation marks the true beginning of the experiment, the sec- ond set of tabulations will be more particularly considered. In all of the tables, the sign X indicates that the animal died; the sign + shows that the animal is still living; the sign ¢ denotes death due to accident; 2/3 is the date of termination of the experiment. The foregoing tables present the data in one comparative way, but as stated above certain facts are brought out more clearly by a different arrangement. In the following tables the comparison begins with the date of operation and a corresponding day for the unoperated animals. 64 JOHN A. LARSON TABLE 1 Control. Ordinary dietary with the addition of liver cuour wounen | sex | 2omawonor | numer asp 75 | canvonnous [PURSION OF Be grams grams days XAG 5 A 50 2 6/4 to 1/20 201 ~=to 246 +45 230 Agel Q 6/3 to 2/3 184 to 180 —4 245+ A 46 2 6/3 to 2/3 232 ~=to 235 +3 245--+ IAL 3 i) 6/4 to 2/3 211 ~~ to 233 +22 244+ A 28 fe) 6/4 to 2/3 189 to 203 +14 244+ A 4 g 6/4 to 2/3 250 to 174 —76 244+ A 20 ot 6 /27 to 2/3 189 to 300 +111 221+ DAS fe) 8 /26 to 2/3 76 ~=to 158 +82 162+ E 34 Q 8 /26 to 2/3 65.5 to 186 +120.5 162+ Ge 2 of 7/8 to 2/3 20 to173 +153 210+ (EF zal Q 7/8 to 2/3 22 ~ to 164 +142 210+ df 12 Q 6/27 to 2/3 35 to 103 +68 221-+- J 90 rot 6 /27 to 2/3 36 = to 194 +158 221-++ Total number of rats = 14. Average gain = 64.5 grams. Total number of rats dead (one was accidental) = 2. Average percentage of deaths = 7.6 per cent. Average duration of experimental life = 219.9 days. TABLE 2 Control. Ordinary diet with the addition of anterior lobe cnove weumen | sex | onamoxor | names span | uy on ross PURAMION OF 2x grams grams days A ll Q 6 /27 to 2/3 281 to 276 —5 221+ A 18 2 6 /27 to 2/3 288 to 336 +48 221+ A 19 oft 6/4 to 2/3 247 = to 304 +57 244+ A 10 ot 6/4 to 2/3 263 to 288 +25 244+ A 82 fe) 6/4 to 2/3 240 to 227 —13 244+ C 16 Q 6 /27 to 2/3 48 to 255 +207 221+ C 57 g 6/27 to 2/3 48 to 233 +175 221+ E 87 of 8/26 to 2/3 49.5 to 154 +104.5 162+ E 16 of 8/26 to 2/3 63.5 to 199 +135.5 162+ F 73 Q 8/7 to 2/3 36 to 206 +170 181+ G 13 ot 8/7 to 2/3 20 to 159 +139 181+ G 57 e) 8/7 tor2/3 21.9 to 128 +106.1 181+ Total number of rats = 12. Average gain in weight = 95.7 grams. Total number of rats dead = 0. Average duration of experimental life, 206.9 days. Percentage of deaths = 0 per cent. FUNCTIONAL CORRELATION OF HYPOPHYSIS AND THYROID 65 Altogether there are ten distinct groups (A to J inclusive), these be- ing arranged according to age, litters, ete. Group A contains thirty individuals, seventeen of which, after a month of study (in nearly every case, see tables 3 and 4) were operated the first week in July. The leg- ends at the heads of the tables are self-explanatory, the X at the left TABLE 3 Thyroidectomized rats fed upon the ordinary diet and liver DURATION Beers fy sex) | Semen On | SA Or | een ea map| Gee oe | ox eeeee LIFE grams grams days oA 9 Q 6/4 to 2/3 6 /24 oA 8 Q 6/12 to 2/38 6/21 | 230 to 205 —25 235-+- xeA ) G6 Q jou toms 7/6 235 to 238 +3 128 XA 4 °) 7/8 to 10/15 7/8 157 to 127 —30 99 X A 91 o | 7/5 to 10/20 7/18 51 to 202 +51 107 XAN) 7 fe) 6/4 to 10/7 6/20 |216 to125 —91 125 De Nea lg ie) 6/4 to 12/2 7/21 |261 to 189 —72 181 AY +8 Q 6/27 to 8/28 6/28 |105 to 84 —21 63 xe AW 22 e) 6/29 to 8/20 7/16 238 to 54.5) -+-31.5 52 XA 33 ofl 7/13 to 9/26 9/13 Iii cOmol: +34 75 X A 29 o | 8/14to 9/4 8/15 73 to 85 +12 21 X D 88 Q 8 /26 to 12 /2 9 /12 46 to 120 +74 98 XD 14 ie) 8 /26 to 10/4 9/12 46 to 56 +10 39 oE 6 i) 8/26 to 9/14 9/13 60.5 to 89 +28.5 19 X E 56 ce) 8 /26 to 11/18 9 /12 45.5 to 76 +30.5 84 ¢ H 27 3 | 8/6 to 1/20 8/9 99 to316 | +217 166 H 32 Oo |.Si/t to 2/3 8/9 79 to315 | +236 179+ xX H 80 so | 8/8 to 8/30 8/9 67.5 to 90 +22.5 22 XI 43 2 8/1 to 12/22 9/19 21 to 89 +68 143 I 45 rot 7/13 to 2/3 9 /20 14 to 189 +175 204+ Beats, 15 Q 6/27 to 9/26 7/18 2ilge OMNId +50 91 Total number of rats = 21. Total number of rats dead = 18. (Three acci- dental deaths). Total number of rats alive = 3. Percentage of deaths =78.9 per cent. Average gain in weight = 40.8 grams. Average duration of experi- mental life = 111.1 days. signifying a death presumably due to experimental conditions or to un- known causes in the controls. The ¢ connotes either an accidental death, doubtless due to shock, etc., as most of these deaths occurred the day following the operation, or to the escape of the animal. The date 2/3 indicates that the individual is still living. THE AMERICAN JOURNAL OF PHYSIOLOGY, VOL, 49, No. 1 66 JOHN A. LARSON Table 5 represents the histories of eight rats. The dates 6/28 and 7/3, were taken as the initial date to correspond with the operative dates. Of the eight individuals there were two deaths, one accidental. The average duration of life of the entire group is 207.8 days. The sign + in last column indicates that the animals are still living. The total TABLE 4 Thyroidectomized rats fed upon the ordinary diet and anterior lobe DURATION DATE OF ANE Gana cakaeaee GROUP NUMBER | SEX | oF EXPERIMENT | OPERATION pate OR LOSS i grams grams days A 35 fof 6/12 to 2/38 6 /25 165 to 161 —4 235+ A 13 g O/B Rito PAB 7/3 98 to 130 +42 245+ A 58 ie) Gi» to u2/3 7/3 157 to 199 +42 245+ A 14 of 6/4 to 2/3 6/18 7 to 250 +163 244+ XA 81 Q 7/6 to 12 /22 7/6 208 to 293 +85 169 X A 12 fe) 6 /27 to 11/30 6 /28 197 to 170 —27 156 GB MI ie) 6/4 to 10/7 6 /25 TL to 133 +62 125 B 51 Q 6/4 to 2/8 6 /20 67 to 229 +162 244+ Bets fot 6/4 to 2/3 6 /25 50 to 276 +226 244+ D 89 fe) 8/25 to 2/38 9/13 56 to 104 +48 16+ ¢ D30 rol 8/26 to 9/22 9 /21 61 to 89 +28 X E 18 Q 8/26 to 11/16 8 /29 67.5 to 116 +48.5 82 DOD) Be Q 8/26 to 10/25 9/13 56 ~=to 104 +48 60 lslalyé Q Site 1602/3 8/9 64 to 196 | --132 181+ H 78 (oh: 8/8 to 2/3 8/9 104 ‘to 134 +30 180+ H 79 of S18) tomas 8/9 97 to 327 | +230 180+ X H 44 rot 8/7 to 10/16 8/7 70. “to “85 +15 60 eo 03 Q 15. 601273 7/10 35 ~=to 104 +69 151 I 24 fof 6/29 to 2/3 7/26 29 to 279 | +250 219+ Sit Q Hae AKO). PIB 7/10 49 to 234 | +185 213+ @ J 70 fe) 8/8 to 11/12 8/12 escaped Zo Total number of rats = 21. Average gain in weight = 105.3 grams. Total number of rats dead = 9; (two accidental). Average duration of experimental life = 179.5 days. Average percentage of deaths = 37.5 per cent. Total number of rats alive = 12. gains in weight are 179 grams and the total losses are 185 grams, making the average 0.75 gram. Table 6 shows the effect of the addition of the anterior lobe to the dietary of the rats. There were no deaths, the average duration of life was 218.6+ days. The average gain for the group is +27 grams. I Sr Say ely Se eS Se as oe ae FUNCTIONAL CORRELATION OF HYPOPHYSIS AND THYROID 67 TABLE 5 Group A. Control, fed upon normal diet and liver ee rex, |) semen er femur | cha cn agns, (eeenon ora, grams ib grams days X A 25 ©) 6 /28 to 12/1 276 to 183 —93 155 A 50 e) 7/3 to 1/20 218 to 246 +28 221+ ACY AA: Q 6/27 to 2/3 175 to 180 +5 221-+- A 46 2 6/27 to 2/3 220 to 235 +15 221+ A 3 OSI NGy27 to, 2/3 222 tO) 230 +11 221+ A 28 ie) TB) WO), 2H 187 to 203 +16 215+ Ay 4 Q (BOs ZAI} 266 to 174 —92 215+ A 20 of (ior ton 2a 196 to £00 +104 215-+- TABLE 6 Group A». Control, fed wpon usual diet and anterior lobe NUMBER | SEX | Zxprniment | MINALWercuT | CATNORLOSS [poe ew nar LIFE grams grams days All 2 6 /27 to 2/3 280 to 276 —4: 221+ A 18 9 6/27 to 2/3 288 to 336 +48 221+ A 19 of 6/27 to 2/3 265 to 304 +39 221+ A 10 rot 7/3 to 2 /3 255 to 288 +33 215+ A &2 Q 7/3 to 2/3 208 to 227 +19 215+ TABLE 7 Group A3. Thyroidectomized rats fed wpon normal diet and liver NUMBER SEX a iene AND TERMINAL GAIN OR LOSS EXPERIMENTAL grams grams days oA 9 Q 6/24 to 2/3 222 to 238 +16 A 8 fe) 6/21 to 2/38 207 to 205 —2 227+ XA 6 ce) 7/6 to 11/8 232 to 238 +6 125 XA 4 fe) 7/8 to 10/15 165 to 127 —38 99 X A 91 Gt 7/13 to 10/20 81 to 102 +21 99 eA 7 Q 6 /20 to 10/7 235 to 125 —110 109 xO AG 7 fe) @ /2etonl2)/2 265 to 189 —76 153 XA 8 fe) 6/28 to 8/28 105 to 84 —21 61 X A 22 Q 7/16 to 8/20 48 to 54.5 +6.5 35 X A 33 a 9/13 to 9/26 55 to dl —4 13 X A 39 ro 8/15 to 9/4 73 to 85 +12 20 68 JOHN A. LARSON Group A;, table 7, shows nine deaths out of ten operated animals, the average life after operation being 71.4 days, and of the group, 94 days. The sign + means that one rat is still living. Thus there is 90 per cent of deaths, an average gain of —20.5 (obtained by adding the gains and losses algebraically and dividing by the number of individuals). Of the rats which died, four showed myxedematous symptoms—rats A6,A4,A7 and A 8. On the other hand group Az, table 8, exhibits 33.33 per cent of deaths and an average duration of life of 201.1 days for the group, that for the two dead being 162 days. TABLE 8 Group As. Thyroidectomized rats fed upon normal diet and anterior lobe , nary INITIAL | DURATION OF NUMBER SEX an) See AND PERMIN AL GAIN OR LOSS =xPaR grams grams days A 35 rot 6/25 to 2/3 175 to 161 —14 223+ A 13 ie) 7/3 to 2/3 128 to 130 +2 215+ A 58 fe) ajs toy 2/3 163 to 199 +36 215+ A 14 of 6/18 to 2/3 87 to 250 +163 230+ xX A 81 Q 7/6 to 12/22 208 to 293 +85 169 XCATAZ fe) 6/28 to 11/30 205 to 170 —35 155 TABLE 9 Group B. Onelitter. Thyroidectomized rats fed upon normal diet and anterior lobe NUMBER SEX ays Atlee: SCTE AND TERAMINAL GAIN OR LOSS EXPERIMENTAL : grams grams days xe Bit ie) 6 /25 to 10/7 93 to 133 +40 104 B 55 ie) 6/20 to 2/3 103 to 229 +126 228+ B 15 of 6/26 to 2/3 75 to 276 +201 223+ Whereas from the previous group there is but one rat alive, here there are four. The average gain is 39.5 grams. A 81 seemed hyper-irrita- ble, very nervous and maintained its head tilted to one side. In B, table 9, another operated group to which the hypophysis was added, one death occurred, with an average duration of life for the group of 185 days and an average gain of 122.3 grams. In C, table 10, there is an average life of 221+ days and gain of 191 grams. FUNCTIONAL CORRELATION OF HYPOPHYSIS AND THYROID 69 In groups D and E, tables 11 and 12, 9/12 is taken as the start of the experiment for the normals to correspond with that of the operated animals, The average life in D was 144 days for the normal; 51.5 days for the operated + liver; and 143+ days for the operated + pituitary; while the average gains were +95, +12.5 and +103; the per cent deaths, 0 per cent; 100 per cent and 0 per cent. TABLE 10 Group C. One litter. Control fed upon normal diet and anterior lobe INITIAL DURATION OF NUMBER SEX 2 eal 3 “19 8 6 13 13 4 BM Ta be | Oe See |e 26 11 4 cs {6 | 53 | 4 | 4 | 5+ 59 93 Ws 2 3 7 Tom Ghee | sSted| eeaalaree 16 6 5 1 Ay He i a age ae ah Wi 2 ee ie 22 2+ 0 2 93°| 6 Sy at g | REMARKS Exposure and manipulation Exposure and manipulation Exposure and manipulation Exposure and manipulation Exposure and manipulation. Long preliminary operation involving ma- nipulation of intestines Exposure and manipulation. Long preliminary operation involving ma- nipulation of intestines Exposure. Scarcely shocked after 11 hours Exposure and manipulation. Position of inflow cannula prevents thorough manipulation Exposure and manipulation. Position of inflow cannula prevents thorough manipulation Evisceration Evisceration Evisceration Exposure in sympathetic-less animal Exposure and manipulation in sympa- thetic-less animal * The time necessary to make the preliminary operation is not included. ** Evisceration was performed immediately and required about 15 minutes. when this was thorough, this fall was accomplished most often in about 4 hours. It is also seen that the pressure was 50 mm. Hg. or lower for from 20 minutes to 3 hours, most often for about 13 hours. STUDIES IN SECONDARY TRAUMATIC SHOCK 99 Peripheral resistance Femoral inflow. The early effect on the femoral inflow rate of expos- ing and manipulating the intestines has not been entirely constant; it is fair to say, though, that practically invariably the inflow rate is reduced, and usually below the initial range (see figs. 3, 4, 5, 8, 9). This con- striction as a rule persists through the period of maintained arterial pressure and often for some time after the arterial pressure begins to fall (figs. 3, 4). It then gradually gives way to dilatation, so that by the time the arterial pressure has fallen to the level of 50 mm. Hg., the 0 Hr. 400 200 3:00 400 5:00 6:00 7:00 Fig. 3. Experiment 7. Shock by exposure and manipulation of the intestines. Arterial pressure, —e—e—; femoral inflow rate, ---e---e---. a, some time after exposure and manipulation; b, three minutes after manipulation; c, asphyxiated to end. inflow rate practically without exception has been as high as, or higher than, the highest initial inflow rate. As the end approaches, the inflow rate often accelerates (figs. 3, 8). Sometimes there is a retardation (asphyxial) at the moment the heart or respiration stops, followed by an acceleration (figs. 5, 8, 9). In some cases a mortal increase in the inflow rate has failed to occur; indeed the asphyxial decrease occurring at this time sometimes has failed to pass off entirely (figs. 3, 4, 9). This occasional failure of the inflow rate to increase beyond the normal after death is worthy of a moment’s consideration. It has been seen not alone after exposure of the intestines but as a matter of fact at the conclusion of long lasting experiments in general and also after adrenalin injections in experiments of even short duration. In part, 100 J. ERLANGER, R. GESELL AND H. S. GASSER at least, it is due to constriction of the larger arteries, including the femoral itself; for the rate of flow through the unclipped artery at this time may be but little faster than the rate through the clipped artery. The first explanation of this phenomenon that suggests itself is that it is due to the formation of an obstruction (a clot) in the artery. But this conclusion is rendered untenable by the behavior of subsequent inflows; for these almost invariably slowly increase from trial to trial (see, for example, fig. 4). The only explanation of the phenomenon that seems at all to fit the facts is that as a result of prolonged asphyxia the arteries pass into a state resembling post-mortem contraction, such as has been described by MacWilliam (12). It is worthy of note that Sollmann and Pilcher (13) found that in post-mortem paralysis of the vasomotor center the outflow, followed by their method, also often did not quite recover its former rate. ° Hr. 12:00 £00 2:00 x00 400 5:00 00 T00 Fig. 4. Experiment 8. ‘Shock by exposure and manipulation of the intestines. Arterial pressure, —e—e—; femoral inflow, -.-e:-e--- a, intestines exposed; b, changed from left to right femoral artery; c, adrenalin, 1.0 ec. 1: 20,000, intra- venously; d, asphyxia. Mesenteric and hepatic inflows. No lengthy explanation is needed to make it clear that mesenteric and hepatic inflows can be followed only with great difficulty in experiments in which the intestines must be exposed and manipulated in such a way as to protect and leave undis- turbed the part into which the injection is being made. We have suc- ceeded in making fairly satisfactory observations in three of the experi- ments. The results, upon the whole, have been the same as in the case of the femoral inflow. In one of the experiments (fig. 5) both the femoral and hepatic (actu- ally hepato-duodenal) inflows were followed. If allowance is made for the fact that the hepatic and femoral readings were not made simulta- neously, the general parallelism of the two inflow curves, excepting the readings made after death, is striking. Some time after manipulation STUDIES IN SECONDARY TRAUMATIC SHOCK 101 of the intestine, and at a time when the arterial pressure reaches about 50 mm. Hg. (5:30), both of the inflow readings are high, the hepato- duodenal being well above the initial range, the femoral at about the upper limit of normal. The terminal (presumably asphyxial) slowing of the femoral inflow rate is followed by the usual post-mortem accel- eration; that of the hepatic, however, is not, possibly because a clot was beginning to form. In experiment 21 (fig. 6) the hepatic and intestinal inflows were fol- lowed. The former showed no consistent changes. It should be noted, however, that at b (see fig. 6) it became necessary to force a clot on into the hepatic circulation. The intestinal inflow was not redetermined until the arterial pressure had fallen to 50 mm. Hg. some 3 hours after exposure of the intestines. The inflow rate then was well above nor- mal. Then, after a lapse of 40 minutes, the inflow rate was found to be markedly diminished and it remained so to the close of the experi- ment. This final decline of the inflow rate might have been due to the slow formation of an obstruction (clot). In experiment 26 (fig. 7) the intestines were merely exposed (at a) and not manipulated. After 10 hours of exposure, the arterial pressure was still 80 mm. Hg., but finally it fell to 52 mm. Hg. After it had been at the latter level for 4 minutes a clot formed in the inflow artery. _ The experiment was then brought to a close by puncturing the heart. Exposure of the intestines in this experiment led to a very marked re- duction in the intestinal inflow rate over a period of 8 hours. Then the inflow rate increased. It reached practically the low limit of normal and was still on the increase at the time the last reading was made. Although these experiments cannot be regarded as entirely satisfac- tory, they nevertheless clearly confirm the results obtained in the study of the femoral inflow rate and indicate that in shock produced by ex- posure and manipulation of the intestines the hepatic and intestinal (splanchnic) areas, as well as the femoral (somatic) area constrict, or, at least, do not dilate, during the early stages of shock induction and di- late as the pressure falls toward the level of 50 mm. Hg. The differ- ences in the behavior of the intestinal inflows in the different experiments possibly are attributable to differences in the amount of handling the intestines suffered, and also to the time relation obtaining between the actual handling of the intestines and determination of the inflow rate. The behavior of the arterial pressure and of the inflow rate as we have described and pictured them applies to the conditions obtaining while the intestines are lying quietly out of the abdomen in the intervals J. ERLANGER, R. GESELL AND H. S. GASSER ce. IS {50 3 = = = 1.0 #00 5/7 50 “00 11:00 3:00 5:00 6:00 7:00 Fig.5. Experiment 19. Shock by exposure and manipulation of the intestines. Arterial pressure, —e—e—; femoral inflow, --* * °; hepato-duodenal inflow, --e--e--. a, manipulation of intestines. Cc. 2.0 200 d =z = = LS 150 1.0 100 5 50 an) 1:00 12:00 1:00 2:00 3:00 4:00 5:00 6:00 Fig. 6. Experiment 21. Exposure and manipulation of the intestines. Ar- terial pressure,—e—e—; intestinal inflow, ---*--*-; hepatic inflow, --e--e--. a, intestines exposed; b, clot in hepatic cannula forced on into capillaries (hepatic). iSO cs z £ rece 100 2 S04 00 a. Hetf00 1200 3:00 4:00 Fig. 7. Experiment 26. Exposure of the intestines. Arterial pressure, —e—+s —; intestinal inflow, --e--e--. a, intestines exposed; b, clot removed from inflow cannula; c, animal killed by puncturing heart. STUDIES IN SECONDARY TRAUMATIC SHOCK 103 between manipulations. When observations are made during, or very shortly after, momentary, though it may be, rough, manipulation of the intestines the result, at least during the first hour or two of the period of shock induction, is quite different. The immediate effect of manipulation then (see fig. 3, b) is a sharp fall in arterial pressure and a momentary, and it may be marked, increase in (femoral) inflow rate. This unquestionably is a passing reflex dilatation. The relation this re- flex bears to the basic change in peripheral resistance occurring during shock development has not been investigated. Interpretation and discussion. Interpretating our results in terms of activity of the vasomotor center, it can be stated categorically that in the early stages of exposure of the intestines the tone of the center usu- ally is increased; that by the time the arterial pressure has fallen to 50 mm. Hg. the tone of the center practically invariably is subnormal, but never is entirely lost. The latter finding confirms Bartlett (9). But even when the tone of the center is subnormal it still is capable of re- sponding in the usual manner to asphyxia produced by suffocation or by sudden stoppage of the heart. The constrictions so induced, though, are very much smaller than those occurring in normal animals. In the last stages of the experiment, therefore, the condition of the cen- ter is below normal as regards both its tone and its reactivity. The fact that vasoconstriction is the rule while the pressure is still high and that dilatation occurs as a rule only after the pressure has been low for some time, would seem to indicate that exposure of the intestines in some way tends to cause a fall in pressure, but that this tendency is combated by the vasoconstrictor center; and that this hyperactivity is maintained as long as the arterial pressure is high enough to maintain a sufficient supply of blood to the centers. It sometimes happens, however, that the inflow rates are not diminished even when the arterial pressure has begun to fall (fig. 8). In such instances, which have been very rare, it must be concluded that the reactivity of the cen- ter to lowered pressure is subnormal. As is well known, there is a large literature, full of contradictions, on the state of the vasomotor center in shock. Inasmuch as practically all these views rest upon observations on, or inferences drawn from, shock as produced by exposure of the intestines or by some comparable - procedure, a brief discussion of this subject is here in order. One cause of the misunderstandings that have arisen in the discussion of this question seems to be a tendency on the part of those holding definite views to overstate the antagonistic views. Thus, those who 104 J. ERLANGER, R. GESELL AND H. S. GASSER have maintained that the cause of shock is to be sought in fatigue, or depression, or exhaustion, or inhibition of the vasomotor center did not as a rule intend to imply, as some seem to believe, that the center is wholly without tone, or wholly unresponsive to its normal stimuli. While another cause of the discrepancies probably is revealed by the fact, brought to light by the present investigation, that the state of vasomotor tone is not the same in allstages of shock. Doubtless differ- ent investigators have been dealing with different stages of shock. An analysis of some of the more important contributions to this sub- ject, with these sources of error in mind, will serve to make our conten- tion clear. It should be stated in the first place that the origin of the view that shock is due to diminished vasomotor activity rests upon inferences from clinical data and from indirect experimental data rather than upon direct methods of attack (14), (15), (16), (17), (18). Porter and col- laborators (19), (20), (21), were the first to approach the problem with a view to testing the then prevailing hypothesis by more direct means than had previously been employed. They succeeded in showing that the fall in arterial pressure on stimulation of the depressor nerve, and that the rise in arterial pressure on stimulation of other afferent nerves are proportionally as great in shocked as in normal animals. They, therefore, maintain that the activity of the vasomotor center is not impaired in shock. Lyon and Seelig (22) using a similar method inde- pendently come to the same conclusion. Sollmann and Pilcher (23) rightly take exception to this method because of a fallacy in the under- lying logic. They point out that a percentile rise in pressure, other things being equal, denotes some loss in activity on the part of the cen- ter; that an unimpaired center should be capable of producing an unimpaired absolute rise in blood pressure. Indeed, it is to us conceiv- able that a percentile rise might actually occur where the center is over- active. Thus a normal center that is stimulated to hyperactivity by a reduction in blood volume, for instance, and which cannot, even as a result of this hyperactivity, keep the arterial pressure up to the normal level, could effect only a relatively small additional, though, perhaps, still percentile, rise as a result of afferent stimulation. Mann’s methods of studing vasomotor tone were indirect (5). He goes further than his facts justify when he concludes that “the vasomo- tor center is not depressed or fatigued in shock;’’ his methods like those of Porter are capable of showing only that the vasomotor center pos- sesses some degree of activity. Joseph and Seelig {24) also employed STUDIES IN SECONDARY TRAUMATIC SHOCK 105 an indirect method of following vasomotor tone. They conclude from observations on the rabbit that in shock the tone of the center is normal. But, as we interpret their results, they demonstrate merely that the center possesses some tone; they are not in a position to state what that degree of tone may be. Muns (25) plethysmographed the leg of the dog and found that trau- matizing the exposed intestines diminished the volume of the leg even when the arterial pressure remained constant. This observation is clearly indicative of a vasoconstriction in the early stage of shock pro- duction and therefore is in accord with our findings. The methods employed by Sollmann and Pilcher (13) and by Morison and Hooker (11) are alike in that they determine the rate of flow of liquid under a constant pressure through blood vessels under the con- trol of the vasomotor center; they, like the method of Bartlett, em- ployed by us, are direct methods. The study of shock was only an incident in the work of Sollmann and Pilcher. In one experiment in which the arterial pressure had been reduced to 10(!) mm. Hg. by manipulation of the intestines the center failed to respond to asphyxia; it had completely lost its activity. Morison and Hooker performed six experiments upon the leg and two each upon the kidney and the intes- tine. It is impossible, though, to tell from their article in what stage of shock they determined the perfusion rate. They state in the text that in but one (leg) experiment the outflow was increased, and in their conclusions state that the rate of flow is decreased. One of us (8) has shown beyond peradventure that tissue abuse at once and defin- itively leads to a reduction in the flow: of blood as measured in the sali- vary gland. Finally, Wiggers (26) concludes (upon the basis of the configuration of the central arterial and intraventricular pressure curves) that from the moment the intestines are exposed and until the death of the ani- mal the larger arteries are abnormaily empty and the peripheral resist- ance low. Wiggers, apparently forgetful of his preliminary discussion, in which several possible explanations are narrowed down to one by a process of reasoning, by no means convincing, maintains that his evi- dence is a direct proof of the condition of the peripheral resistance, a conclusion with which we cannot agree. But, assuming for the moment that the method does indicate a diminution in peripheral resistance, it does not necessarily follow, as Wiggers himself admits, that the dimin- ished peripheral resistance is the result of diminished central tone. The present methods have shown that early in shock production, ex- 106 J. ERLANGER, R. GESELL AND H. S. GASSER cepting only the momentary response to manipulation of the intestines, the center, as a rule, maintains increased tone, both in the somatic area and in the parts of the splanchnic area that are not injured. We have not measured the peripheral resistance in the parts of the splanchnic area directly traumatized. According to Janeway and Ewing (27), manipulation of the intestines paralyzes the splanchnics locally, while in loops protected from exposure the vasomotor tone remains normal. This, presumably, is entirely a peripheral process. But inasmuch as the exposed loops are also the seat of an inflammatory process, it does not necessarily follow that the resistance to the flow of blood through them is diminished by the splanchnic paralysis. In the light of our direct determinations of the peripheral resistance in the early stages of intestinal exposure, it is obvious that only if the resistance were diminished in the traumatized regions would there be a way of ac- counting for the peculiarities of Wigger’s central pressure curves on the basis of a reduction in resistance. As a matter of fact, the evidence available seems to support increased resistance to blood flow through- out the splanchnic area, rather than diminished resistance; forall inves- tigators are agreed, as will be seen in a moment, that the portal pres- sure is lowered by intestinal exposure. A diminution in the resistance to blood flow in the intestinal area would have just the opposite effect. Our experiments, as has been said, seem to indicate that in part, at least, the late loss in vasomotor tone is the result of the reduced blood flow that comes of the low pressure rather than the cause of the low arterial pressure. It is therefore conceivable that if shock could be . Induced more rapidly than we have succeeded in bringing it on, a low pressure might develop at a time when the tone of the center is still high. In such a case marked constriction might persist to the end. Jugular pressure The jugular pressure in the two experiments in which it has been followed (figs. 8, 9), varied at most 0.5 mm. Hg. Morison and Hooker (11) found that the caval pressure progressively falls; and Wiggers found that the so-called effective venous pressure falls. In shock pro- duced by this method, therefore, the heart seems to be capable of mov- ing on efficiently all the blood that is brought to it. This confirms the conelusion Mann (5) and others have come to on the basis of observa- tions of another kind. - STUDIES IN SECONDARY TRAUMATIC SHOCK 107 Here we may refer to a few casual observations made with the idea of testing the capabilities of the heart. In a few experiments we have from time to time determined the height to which the carotid pressure is raised when the aorta is temporarily occluded. This may be consid- erable even quite late in the course of the experiment, but it is not equal to that attained early in the experiment, nor is the raised pressure so well maintained. This failure of the heart in shock to equal the performance of the heart in the normal animal does not necessarily mean that the heart is at fault. For in shock the respiratory pump is apt to be feeble and the return of blood to the heart impaired. Portal pressure The portal pressure has been followed through one experiment and almost to the close of another. In the one complete experiment (fig. 8), upon exposure of the intestines the pressure fell from the unusu- ally high level of 16 mm. to 7 mm. in the course of 23 hours. Owing to trouble caused by clotting, the data with regard to the peripheral resistance are of but little help here in arriving at an understanding of this behavior of the portal pressure. It might, though, have been due entirely to the fall in arterial pressure. Later (after 2:00) the portal pressure rose for about 1} hours; the fall in arterial pressure at this time was continuous. The inflow rate, here, is again confused by clotting; but later, when the shift was made to the other femoral artery, it was found that the peripheral resistance was diminishing. It is possible, therefore, that the rise in portal pressure which here occurs despite a falling arterial pressure, is to be explained by a giving way of the peripheral resistance. Later, the portal pressure begins to fall again and this fall is continuous to the end. Very little dilatation occurs during this last phase of the experiment. The falling arterial pressure may therefore be the cause of the fall in portal pressure. In the other experiment (fig. 9) the behavior of the portal pressure was quite similar to that seen in the preceding case. After exposure of the intestines the pressure fell more or less steadily from 7.5 mm. Hg., reaching 5 mm. Hg. in the course of 2} hours. In the presence of a constant arterial pressure this fall may fairly be attributed to the pe- ripheral constriction indicated by the inflow readings. During the next 3 hours the portal pressure was practically stationary. In the same period the arterial pressure for the most part was falling, while the in- flow readings were quite variable; so much so that the data furnish no clear basis for the interpretation of the behavior of the portal pressure. 108 J. ERLANGER, R. GESELL AND H. S. GASSER - Our finding that exposure of the intestines, upon the whole, lowers the portal pressure, confirms Morison and Hooker (11), in most of whose experiments the animal was merely kept on the table under an anes- thetic until the arterial pressure fell. Cun 20 1220 +00 700 $0 +00 $00 Fig. 8. Experiment 58. Shock by exposure and manipulation of the intestines. Arterial pressure, —e—e—; femoral inflow, -*® -* --; portal pressure, —e—o—} jugular pressure, X ™X. a, intestines exposed; b, partial clot in inflow cannula; c, clot removed; d, accidental injection of carbonate, respiration stopped but re- covered in 8 minutes; e, changed to other femoral artery. i % > ead ween, Proan: Hr. 12:00 £00 2:00 300 4:00 5:00 6:00 700 8:00 Fig. 9. Experiment 59. Exposure and manipulation of the intestines. Ar- terial pressure, —e—e—; femoral inflow, -*:*'-:*:- ; portal pressure, —e —e—; jugu- lar pressure, X X. a, abdomen opened;b, changed to other femoral artery; c, abdomen opened wider; d, injected strong carbonate; e, heart stabbed. Inspection In experiments of this kind one gains the impression that the larger veins of the splanchnic area do not contain more blood when the ani- mal is in shock than when the intestines are first exposed. It is realized, however, that this method of estimating venous engorgement is too sub- jective to be of any great value, as is evidenced by the conflicting opin- ions of different observers. STUDIES IN SECONDARY TRAUMATIC SHOCK 109 When the intestines are first exposed, the peritoneum covering them is perfectly smooth and glistening. In time, however, fine beads being to form on it; these run together forming larger beads and eventually the fluid so formed streams off the bowels in considerable amounts. In several experiments, by placing the bowels on a tilted glass plate, the larger part of the fluid thus exuding was collected over definite periods. At times it dripped away at the rate of over 1 cc. per minute. The total amount formed probably never has exceeded 150 ec. This weep- ing of the peritoneal surface probably accounts in part for the concen- tration of the blood that occurs in this type of shock. The bowels also become boggy to the touch as though they were edematous. A certain amount of fluid must be abstracted from the circulation by this process also. At post-mortem examination, petechial hemorrhages into the serosa are not uncommonly found. The mucosa of the intestines is deeply congested, of a deep, bluish-red color and the lumen of the bowel may contain some bloody material. On microscopical examination there is found relatively little hemorrhage into the mucosa. But the capilla- ries and the veins of the villi are tremendously distended with solid col- umns of corpuscles. It is undoubtedly this that gives the mucosa its deep red color, rather than the hemorrhage. Summary The immediate effect of exposure of the intestines usually is a vaso- constriction, often of a moderate grade (as compared with some other shock-producing procedures to be described later) affecting both the somatic and the splanchnic areas, with the possible exception of the parts directly traumatized; a fall or no change in the arterial pressure; a fall in portal pressure; and a slight, probably unimportant, change in the pressure in the right auricle. In view of the fact that the energy of the heart at this time is not reduced, this combination of effects seems to be accounted for best upon the basis of a reduction in effective blood volume; possibly also upon the basis of a dilatation in the trau- matized region. The fact, however, that the portal pressure falls seems to exclude the latter, and to lend support to the view either that con- striction is occurring in the traumatized area as well as elsewhere, or that exposure of the intestines mechanically interferes with the empty- ing of the veins of the splanchnic area, or that the distention of the splanchnic capillaries and venules with masses of corpuscles blocks 110 J. ERLANGER, R. GESELL AND H. S. GASSER the entrance of blood into the portal area. Weeping from the serous surface of the injured viscera must tend toward reducing the blood volume. The later consequences of exposure of the intestines are: continua- tion of the fall in arterial pressure; eventual diminution in vasomotor tone; and a slight rise, or a cessation of the fall, of the portal pressure. The absence of constriction, indeed, the development of an actual dila- tation in the face of a low arterial pressure bespeaks a giving way of the vasomotor center. This giving way, presumably, is largely a reaction on the part of the center to the long-continued unfavorable conditions, among which must be included the low arterial pressure. The vaso- constrictor center, though, preserves a certain amount of tone and of reactivity to the end. The capillaries and veins of the villi of the in- testines are greatly distended with blood. SHOCK IN ANIMALS DEPRIVED OF SYMPATHETIC CONTROL! Reflex inhibition of the tone of the vasoconstrictor center, affecting the splanchnic area in particular, may be regarded as one of the earliest of the hypotheses of shock founded upon experimental observation. If reflex inhibition of the constrictor center is the cause of the shock that results after exposure and manipulation of the intestines, it was felt that it should be more difficult to bring on shock in animals so prepared that there would remain but little opportunity for the play of such re- flexes. It also has been maintained that shock is due to constriction of the portal radicles in the liver with consequent damming back of blood in the portal area. A number of methods are available cf putting these views to the test of experiment. One that we employed consisted in studying shock- producing procedures in animals after cutting the splanchnic nerves and removing the abdominal sympathetic chain. In this way the sym- pathetic connection of the abdominal viscera with the central nervous system is severed and the possibility of vasoconstrictor reflexes to them, to the parietal peritoneum, as well as to a large part of the soma, is excluded. Two animals survived this rather difficult operation long enough for the immediate effects to wear off. Several weeks later the effects of traumatization were studied. The initial arterial pressures of these 1 These experiments were done by one of us (H. S. G.) with the assistance of B. Landis Elliott. STUDIES IN SECONDARY TRAUMATIC SHOCK ah animals were 80 and 100 mm. Hg.—not as low as was anticipated in the absence of the central vasoconstrictor control of practically all of the vessels below the level of the diaphragm. Experiment 22. In this experiment, the data of which are collected in figure 10, the arterial pressure was falling when the registration of the pressure was begun, and by the time the abdomen was opened it had already practically reached the level of 50 mm. Hg. The fall in arterial pressure (‘‘shock’’), therefore, can scarcely be attributed in this case to the exposure of the intestines. Excepting possibly a slight increase early in the experiment and one aberrant reading, the inflow rate, followed in both the right and left femoral arteries, remained prac- 11:00 12:00 1:00 2:00 ; 3:00 Fig. 10. Experiment 22. Shock after excision of abdominal sympathetic chain and section of the splanchnic nerves. Arterial pressure, —*—*—; right femoral inflow, --**-**-; left femoral inflow, --e--e--. a, abdomen opened; b, adrenalin injected. tically constant through shock and death. Evidently the preliminary operation had accomplished its end. Experiment 26 (fig. 11). A pressure of 50 mm. Hg. was reached in something over 2% hours after opening the abdomen, and the animal died about 34 hours later. Early in the experiment each manipulation of the intestines (6, fig. 11) caused the arterial pressure to fall and the femoral vessels to dilate. This reaction presumably was mediated through the vasodilator mechanism; for the femoral area, the area in which the state of tone was followed, was isolated from the vasocon- strictor center by the preliminary operation. The afferent path of this reflex must, therefore, have been by way of the visceral fibers of the vagus nerve (28). Excepting these fluctuations, the inflow rate was 112 J. ERLANGER, R. GESELL AND H. S. GASSER never, not even after death, more than 0.2 cc. per minute above or be- ‘ow a rate of 1.6 cc. per minute. Manipulation of the intestines in this case obviously hurried the animal into shock. These two experiments prove that the preliminary operation had ac- complished its object of freeing the lower parts of the body from vaso- constrictor influences. The level of 50 mm. Hg. was reached in one (exp. 22) about 1 hour after starting the record; in the other, in some- thing less than 3 hours. Shock, therefore, developed faster in these animals than in any other of the animals in which it was induced by exposure of the intestines. The explanation of this fact may lie either in the rundown condition of the animals at the time they were experi- mented upon, or in the liberation of a large part of the body from vaso- constrictor control. If the latter is the correct explanation, it would Fig. 11. Experiment 23. Shock by exposure and manipulation of the intes- tines after excision of the abdominal sympathetic chain and section of the splanchnic nerves. Arterial pressure,—*—*—; femoral inflow, -"* -*--*. a, abdomen opened; 6, b, intestines manipulated. constitute a reason for believing that the vasoconstriction usually pres- ent in the earlier stages of shock development in the case of undener- vated animals is, as we have every reason for believing, an effort at com- pensation of something that is tending to lower the arterial pressure. Furthermore, if the shock that is induced by exposure and manipula- tion of the intestines is due to the accumulation of blood in the splanch- nic area, these experiments would serve to indicate that the accumulation is not attributable to the trapping of blood in the portal area through constriction (29), nor to a dilatation that comes about through loss of vasoconstrictor tone. The increased capacity of the peripheral vessels must develop either through the action of some local mechanism or through continuous central vasodilator stimulation. ‘The latter alter- native, to say the least, is highly improbable. ae ee a ee ee. ee = STUDIES IN SECONDARY TRAUMATIC SHOCK 113 SHOCK IN EVISCERATED ANIMAS Three animals have been followed through sho¥k after removing the stomach, intestines and spleen. The operation was performed in such a way as to carry away with these organs a minimum of blood. The results in all three experiments avere essentially alike (see fig. 12). The arterial pressure was well maintained for a while and then fell gradually, reaching the 50 mm. Hg. level i 3, 4 and 6 hours, respec- tively. Evisceration was always followed by a reduction in the femoral inflow rate lasting as long as 2 or more hous; in the case used here for purposes of illustration the constriction was the least marked and the most transient of all. At about the time the arterial pressure begins to fall rapidly, vasoconstrictor tone begins to give way and it becomes subnormal long before the animal dies. Dea”h has occurred in from 43 to 7 hours. Hr. 11:00 12:00 4:00 2-00 3:00 4:00 3:00 Fig. 12. Experiment 17. Failure of the circulation after evisceration. Ar- terial pressure, —*—*—; femoral inflow, * -*-- Ata, the stomach, intestines and spleen were excised. Discussion. These experiments were performed with the idea of testing the view, widely held, that the splanchnic area is primarily the location in which are enacted the events that lead to shock. This rdle has been assigned at various times to such processes as the accu- mulation of blood in the splanchnic and portal capillaries and veins due to splanchnic dilatation, the damming back of blood in the portal area as a result of an increase in hepatic resistance, loss of tone in the portal system, loss of blood ‘‘due to the reaction of the great delicate vascular splanchnic area to irritation—an acute inflammation of the perito- neum,”’ (5), ete., etc. Some investigators have gone so far as to main- tain that shock can be produced in animals solely by exposure and ma- nipulation of the intestines. THE AMERICAN JOURNAL OF PHYSIOLOGY, VOL. 49, No. 1 114 J. ERLANGER, R. GESELL AND H. S. GASSER The present experiments demonstrate not only that typical shock develops in animals.in which none of these mechanisms has a chance to work, but in addit*on, that the vasomotor reactions and the duration of the several stages of shock development (see table 1) are essentially the same in the eviscerated as in the uneviscerated animal. Indeed, the vasoconstriction of the early stages of shock induction is more marked in the former even than in the latter. We do not wish to give the impression that exp sure and manipulation of the viscera are not factors in the development of shock; the present experiments merely demonstrate that after th! animal has been started on its way to shock, partly perhaps through the handling of the viscera that evisceration entails, none of the above-mentioned mechanisms is needed to hurry the animal along its downward course. SUMMARY AND CONCLUSIONS The changes in the circulation found in this investigation to occur during the development of shock brought on by exposure and manipu- lation of the intestines are as follows: 1. The arterial pressure at first may be lowered but little, if any. After some time, it may be after some hours, the pressure begins to fall, and this fall then continues more or less steadily, though often slowly, until the animal dies. 2. The changes occurring in the systemic venous pressure have been so small that they cannot be regarded as significant, excepting, perhaps, in demonstrating that cardiac failure has little, if anything, to do with the failure of the circulation. 3. The portal venous pressure falls continuously, though slowly, during the first 2 to 3 hours. It then ceases to fall or actually rises slightly until the arterial pressure has reached a comparatively low level, when the portal pressure again begins to decline. 4. The peripheral resistance, both somatic and splanchnic, at first practically invariably is increased. At about the time the arterial pressure begins to fall, or starts on its steady decline, and also at about the time the portal pressure starts to rise, the peripheral resistance be- gins to diminish and by the time the arterial pressure has reached the vicinity of 50 mm. Hg., the peripheral resistance practically invariably is below normal. But up to the time of death the vessels preserve some residual tone and the vasomotor center some, though slight, reactivity. In this respect the findings of Bartlett (9) are completely confirmed. dntetnniiie e STUDIES IN SECONDARY TRAUMATIC SHOCK 115 5. A considerable loss of fluid from the exposed bowel occurs as a re- sult of transudation through the serous surface, and presumably into the tissues also. The capillaries and veins of the intestinal villi are greatly distended and tightly packed with red corpuscles. 6. No positive evidence has been obtained that the efficiency of the heart is impaired during the development of shock. Nevertheless, al- though the heart is capable of raising the arterial pressure as high as can the normal heart, we are inclined to believe that the heart in shock cannot maintain high pressures as long as can the normal heart. 7. The initial changes in the circulation can be explained best upon the assumption that the effective blood volume is reduced. The loss of fluid into and through the tissues of the bowel and the se- questration of blood in the intestinal capillaries and venules suggest a mechanism through which a reduction in blood volume might occur. But if this is the mechanism, the fact that after excision of the stom- ach, intestines and spleen the arterial pressure falls almost exactly in the same way as after exposure of and manipulation of the intestines, and the fact that the changes in peripheral resistance are also alike, necessitate assuming that blood is thus removed from circulation, not alone in the parts of the body directly traumatized, but elsewhere also. It is impossible to determine, on the basis of the present experiments, what role, if any, the preliminary constriction plays in the subsequent failure of the circulation. But the experiments in which, by excision ‘of the abdominal sympathetic chain and section of the splanchnic nerves, the entire posterior half of the body was removed from vasocon- strictor control, indicate, as might have been anticipated, that vasocon- striction is not essential to the development of a shock-like failure of the circulation. Although at first the vasomotor center, as a rule, strives, by increasing the peripheral resistance, to compensate the processes that are tending to lower the arterial pressure, the reactivity of this center becomes sub- normal long before the arterial pressure has fallen to the level of 50 mm. Hg.; this ultimate failure of the center to respond with a strong constriction to the stimulus of a low arterial pressure must be regarded as a secondary factor in the development of the low arterial pressure in - this type of shock. 116 J. ERLANGER, R. GESELL AND H. S. GASSER BIBLIOGRAPHY (1) Eruancrr, GEseLL, GAsseR AND Exuiort: Journ. Mo. State Med. Assoc., 1918, xv, 30; Proc. Amer. Physiol. Soc., This Journal, 1918, xlv, 546; Journ. Amer. Med. Assoc., 1917, ]xix, 2089. (2) Gasser, ERLANGER AND MEEK: Journ. Mo. State Med. Assoc., 1918, xv, 282; Proc. Amer. Physiol. Soc., This Journal, 1918, xlv, 547. (3) ERLANGER AND GassER: Journ. Mo. State Med. Assoc., 1919, xvi, 98. (4) Cowrtu: Journ. Amer. Med. Assoc., 1918, lxx, 607. (5) Mann: Johns Hopkins Hosp. Bull., 1914, xxv, 205. (6) Mann: Surg., Gynec. and Obst., 1915, xxi, 430. (7) ARCHIBALD AND McLean: Ann. Surg., 1917, Ixvi, 280. (8) GesELL: This Journal, 1919, xlvii, 468. (9) BartLett: Journ. Exper. Med., 1912, xv, 415. (10) SotuMANN AND Piucuer: This Journal, 1910, xxvi, 233. (11) Mortson anp Hooxer: This Journal, 1915, xxxvii, 86. (12) MacWitu1am: Proc. Royal Soc., 1902, Ixx, 109. (13) SoLLMAN AND PitcHEeR: This Journal, xxix, 1911, 104. (14) Keane, MitcneLtt AND Morenovse: Cire. no. 6, Surgeon General’s Office, 1864. (15) Fiscurer: Samml. klin. Vortrige, 1870, x, 69. (16) Metrzer: Arch. Int. Med., 1908, i, 571. (17) CriLte: Experimental inquiry into surgical shock, Philadelphia, 1899. (18) Howeuu: Vaughan’s Anniv. Vol., Ann Arbor, 1903, 51. (19) Porter: This Journal, 1907, xx, 399. 20) Porter AND Storey: This Journal, 1907, xviii, 181. (21) Porter AND Quringy: This Journal, 1908, xx, 500. (22) Lyon AND SEEtiIc: Journ. Amer. Med. Assoc., 1909, li, 45. (23) SOLLMANN AND Pitcuer: This Journal, 1910, xxvi, 233. (24) JosEPH AND SEELIG: Journ. Lab. and Clin. Med., 1915, i, 283. (25) Muwns: Proc. Soc. Exper. Biol. and Med., 1915, xii, 87. (26) Wiacrrs: This Journal, 1918, xlv, 485. (27) JANEWAY AND Ewina: Ann. Surg., 1914, lix, 158. (28) Foranov AND Tscua.ussov: Arch. f. d. gesammt. Physiol., 1913, cli, 543. (29) Cannon: Boston Med. and Surg. Journ., 1917, Ixx, 615. PROCEEDINGS OF THE AMERICAN PHYSIOLOGICAL SOCIETY Tuirty-First ANNUAL MEETING Johns Hopkins University, Baltimore, April, 24, 25, 26, 1919 IN MEMORIAM Admont Halsey Clark Ralph Edmond Sheldon Frank Fairchild Wesbrook The CO, dissociation curve as the complete expression of the acid base equilibrium of the blood. YANDELL HENDERSON and Howarp W. HAGGARD. In studying some problems of asphyxia and acidosis, we had occasion to plot a series of CO: dissociation curves. The data were from the blood of a dog which had received increasing amounts of HCl intra- c venously; and we made the follow- i , ing observation. With increasing dosage of acid and neutralization of the NaHCO; of the blood, the curves / ha came to progressively lower levels. : At the same time the points in the Heal 8 esa ey curves corresponding to the arterial ical blood, (the points A/ to A4 in the figure) fell further and further to the left. Furthermore when these arterial points were connected they were found all to lie on or close to a diagonal straight line, and this line when continued passed through the intersection of ordinate and abscissa. Consideration of these graphic relations shows that such a line ex- presses the same C,, at every point throughout its length, for all points in it indicate the same ratio of dis- solved CO. to combined CO... We 10 20 30 40 50 60 70 term it the O-C line, or line of C M.M. CO Aer VOIUMES PERCENT CO; 118 AMERICAN PHYSIOLOGICAL SOCIETY values. It expressed the inherent sensitiveness of the respiratory center to its chemical control. It demonstrates that the C, and not the total CO, in the blood (i.e., not the concentration of HCO; ions) is the hormone of respiration. It enables us to modify the Haldane-Priestley law of respiration thus: The volume of the pulmonary ventilation varies inversely as the amount of alkali which in the condition of the blood at the time will afford the normal Cx. In other words, normal respira- tion adjusts the tension and content of COs, i.e., alkaline reserve, in the arterial blood to values corresponding to the point of intersection of the dissociation curve, whether high or low, with the O-C line. Study of the CO, diagrams of many types of experiment shows that instead of merely two possible abnormal conditions, acidosis and alka- losis, there are theoretically four: a, high NaHCO; and high C,; 6, low NaHCO; and high C,; c, high NaHCO; and low Cy; and d, low NaHCO; and low Cy. Regarding these four conditions, a probably occurs only in morphin poisoning and related conditions; b is the condition now termed uncompensated acidosis; ¢ is perhaps what is now termed alka- losis; d is a condition which has not heretofore been distinguished from b. Inits nature and proper mode of treatment d is however profoundly different from b. (The C, scale given in the figure is merely illustrative). Studies on the responses of the circulation to low oxygen tension. I. Types of variation in blood pressure and heart rate. CHaAs. W. GREENE. Schneider! has established the general type of compensation made by men undergoing the Air Service test to low oxygen tension in which the percentage of oxygen is gradually decreased during rebreathing. The heart rate isincreased. The acceleration is slight at first beginning at from 16 to 12.2 per cent oxygen and growing more and more pro- nounced to the end of humanendurance. The total increase may reach forty beats or more in an adequate reactor. In the ideal type systolic pressure holds till late in the test, till the oxygen is lowered to 14 to 9 per cent, then gives a gradual rise. The diastolic holds or rises slightly in the early stage and shows a fall at the low oxygen level often very marked at the end of the test. These are Schneider’s types and he has published data including type charts in the Manual of the Medical Research Laboratory of the Air Service, War Department, 1918. A number of marked variations from the types are selected and pre- sented here for discussion, both from the cardiac group and from the vasomotor group. These types indicate that vascular compensation may be accomplished by a number of variations from the type. The following are listed: a, A sharp increase both in heart rate and systolic pressure at the beginning of the test, which hold at the new level and show the typical heart rate and blood pressure compensations to the end of the test. 6, A high initial blood pressure response that holds on the new level with more than the average increase in the late stage of the test, but with slight compensation in heart rate. c, The converse of * Journ. Amer. Med. Assoc., 1918, lxxi, pp. 1382-1400. aa PROCEEDINGS 119 type b, a great increase in heart rate beginning early in the test and pro- gressing to the end but coupled with little or no systolic compensation and often with early diastolic fall. d, Unusually high systolic pressures that fail in compensation and tend to collapse. The possible significance of these types is discussed. Variations in alveolar air at low pressures. BRENTON R. Lutz. A preliminary report of twenty-four cases in which the alveolar air tensions were determined under conditions of rapid reduction of atmos- pheric pressure is presented. Reduced barometric pressures were produced in one of the low pressure chambers at the United States Army Medical Research Laboratory, Mineola, L. I., N. Y., at a rate simulating an air-plane ascent, that is, 352 mm. Hg. or 20,000 feet were attained in twenty minutes. Alveolar air samples were taken in Hen- derson alveolar air sampling tubes after the expiratory method of Haldane and Priestley. These were analyzed for oxygen and carbon dioxide with a Henderson-Orsat gas analyzer. Samples were obtained at sea level, 4,000 feet, 8,000 feet, 12,000 feet, 16,000 feet and 20,000 feet. The average curve for oxygen and carbon dioxide shows a fall present at the fourth minute and continuing until the ascent was completed. The average sea level values were 103 mm. Hg. for oxygen and 39.6 mm. Hg. for carbon dioxide. The average values at 4,000 feet were 83.7 mm. for oxygen and 37.0 mm. for carbon dioxide; for 8000 feet, 66 mm. and 36 mm. respectively; for 12,000 feet, 53.2 mm. and 33.5 mm.; for 16,000 feet, 42.6 mm. and 31.3 mm.; for 20,000 feet, 34.8 mm. and 30 mm. These twenty-four cases indicate that in an ascent at the rate of 1000 feet a minute both the alveolar oxygen tension and the alveolar carbon dioxide tension begin to fall very early, reaching at 20,000 feet, 34.8 mm. Hg. for oxygen and 30 mm. Hg. for carbon dioxide. Variations in respiration volume and oxygen consumption during the reduction of the oxygen tension and during short exposures at the reduced oxygen level. Max M. ELLIs. The changes in respiration volume and oxygen consumption of men at sea level, during the reduction of oxygen and during the first ten minutes at the new level of reduced oxygen, were obtained from a rebreather containing 54 litres of air. The carbon dioxid produced by the subject was removed by a potassium hydroxid cartridge. The general response in volume was an increase in the per minute volume, as compared with the sea level volume, during the reduction of. oxygen, followed by a decrease in the volume moved while at the new level of reduced oxygen. The per minute volume at the reduced oxygen level remained consistently higher than the sea level volume. The increase in volume moved was initiated in most cases before 17.5 per cent oxygen. was attained. The general response in oxygen consumption was the same as that in volume, a rise in the per minute oxygen consumption above the sea level 120 AMERICAN PHYSIOLOGICAL SOCIETY value during the reduction of oxygen, followed by a fall in the per minute consumption at the new level of reduced oxygen. The value at the reduced oxygen level was higher in the majority of cases than the sea level value. The responses were more profound in subjects carried to equivalent altitudes above 10,000 feet. Phenomena following indirect concussion of ‘he skull. T. S. GirHens and 8. J. MELTZER. Concussion was produced in completely etherized dogs by a weight falling on a board 4 cm. thick laid on the head in front of the occiput. Complete unconsciousness continued till the end of the experiment. We wish to report briefly the following phenomena which were observed. Brain. The lid and corneal reflexes were never lost. The eyes showed nystagmus for an hour or so after the concussion and afterward were moved in an apparently normal manner. Stimulation of exposed sensory nerves (e.g., supra-orbital) caused no sign of pain and no in- fluence on respiration or other reflex effect even after four hours. A new nose-licking reflex was noted. If the nasal septum were pinched by forceps, no response occurred during the pressure, but on releasing it the tongue was protruded and licked the nose. This was seen in all the dogs in which it was systematically looked for. Medulla. The medullary centers were surprisingly little affected. The blood pressure was usually very high soon after the concussion, and the respiration was noisy and irregular, soonbecoming normal. Section of the vagus nerves interfered with respiration as in decerebrate animals. After section of one vagus, stimulation of the central end caused active expiration or expiratory stoppage. Cord. For the first hour or so there was complete paralysis with loss of all reflexes and responses. Later, circulatory, respiratory and spinal reflexes returned and often became exaggerated. Many of the dogs showed a generalized tremor beginning within an hour and lasting until the animal was killed several hours or even a day later. In three dogs there was some indication of returning pain sense after two or three hours. Stimulation of the sciatic nerve after return of reflexes caused stiffness of one or more legs, often associated with emprosthotonos of the abdominal region and opisthotonos of the cervical; the pelvis being drawn forward and the head backward. Similar phenomena were obtained from stimulation of the brachial plexus. The muscles of the head itself were never involved. Stimulation of the cervical nerves never caused any response except active expiration. Lesions. Only gross study of hemorrhage was made. The only characteristic lesion was a hemorrhage into the upper part of the cord extending from the calamus to the second or third cervical nerves. This was associated with laceration of the gray matter extending from the central canal into the dorsal horns. There was almost no hemorrhage within the skull. Ce wape ‘ PROCEEDINGS 121 Physiological effects of air concussion. D. R. Hooker. Through the assistance of the National Research Council and the codperation of the Ordnance Department of the Army, facilities were obtained for the study of the physiological effects of air concussion in animals. For the most part, anesthetized dogs were used. They were exposed at varying distances in front of large calibre rifles and if the con- cussion pressure amounted to approximately twenty atmospheres, a shock-like result was obtained, i.e., the arterial pressure fell immediately (five minutes) from a control value of 100-150 mm. Hg. to 40-60 mm. Hg. After this condition was established, the animals remained alive for one to ten hours and efforts were directed to a study of some of the con- comitant phenomena. Both the pulse and respiration were accelerated presumably as the result of the lowered arterial pressure. In a single ease the blood catalase was not reduced. The alkaline reserve was normal immediately after exposure but fell markedly in the course of an hour. No air bubbles could be found in the vascular system nor was there evidence of intravascular fat sufficient to account for the results. The medullary reflexes, so far as tested, were all normal. That is to say, respiratory, cardiac and vasomotor responses were readily elicited upon sensory nerve stimulation. The eye-lid reflex was active. The most interesting result was found in the venous side of the cir- culation. The venous pressure invariably showed a fall. This pressure was down immediately after exposure and continued subnormal until death, an observation which suggests, in view of the efficiency of the vasomotor mechanism, an inadequate venous filling as a causative phenomenon of the condition. This suggestion is strengthened by the appearance of the abdominal veins. If examined late in the condition, the veins were small, dark and relatively inconspicuous. If examined shortly after exposure, they were obviously very much enlarged. The fact that this enlargement of the abdominal veins accompanied a low venous pressure may be interpreted as indicating a failure of the veno- pressor mechanism. The late appearance of the veins, according with clinical observation, is doubtless due to transudation of blood plasma. The sole pathological lesion found was a scattered hemorrhagic con- dition of the lungs, as has been noted by Crile. It is conceivable that this tissue injury released a toxic substance adequate to establish shock. But the extent of injury did not run parallel with the symptoms; in fact, many animals with an extreme grade of pulmonary involvement failed to show circulatory collapse. Onthe generalexpression of thelaw of cicatrizationof wounds. P. LECcOMTE pu Not. The cicatrization of surface wounds is a phenomenon which 1s likely to involve quite a great number of elementary phenomena. But as all the latter are related to each other by definite, although unknown, laws, it seemed that the resulting phenomenon, cicatrization, could be studied in the same way as the ordinary physico-chemical phenomena, in order 122 AMERICAN PHYSIOLOGICAL SOCIETY to see whether a general law could be assumed. To comply with this purpose, a technique had to be developed for measuring accurately the area of wounds. Sterilized cellophane was applied to the wound, and the edge was outlined with a wax pencil. This drawing was transferred in ink to an ordinary sheet of paper, and the area was measured by means of a planimeter. A curve was obtained by carrying the area, in square centimeters, in ordinates, and the time, in days, in abscissae. A great number of experiments on animals and on human beings during the war, brought forward a great number of interesting facts, which we shall try to review rapidly. At first it was shown that the cicatrization of a wound was due to two different factors: contraction and epithelization, the first one being the most important.!. When the wound is kept aseptic, the curve represent- ing the cicatrization plotted as above said is perfectly geometric, and can be expressed by a mathematical formula. In this formula enters a certain coefficient, which we called ‘‘i,” or index of cicatrization, which is inversely proportional to the age of the patient or of the animal. This means that by making one single measure of the area of the wound, and provided the age of the patient is known, one can draw the curve repre- senting the normal healing of a wound.? Beside its scientific interest, this has many practical advantages. First: It allows the physician to compute. the total time which is necessary for the wound to heal. Second: It gives indications as to the “physiological age of the patient”’ which, indicated by his own curve, may differ from his real age. Third: When it has been proved that a wound heals normally, comparison between the calculated and the observed curve will indicate the real value of the substance which is used on the dressing.’ This latter technique has been extensively used during the war to ascertain the action of antiseptics. It was found that most of them were irritating and interfered more or less with the normal process of cicatri- zation. Having a daily witness, a standard curve, to which the observed curve was always compared, it was a very easy and rapid work to deter- mine the value of the so-called ‘‘cicatrizing substances.’’ We found that no such thing exists so far. The ideal condition of perfect and most rapid healing is realized when the wound is kept practically sterile, or deprived of pathogenic microbes such as cocci, diplococci, streptococci and so forth. These conditions were realized with the Carrel method. A device for injecting fluids intravenously. P. LecomTE pu Noty. This device does away with piston, gears and valves. The only part which has to be sterilized is the piece of rubber tubing which is used with the needle. It aspirates and compresses, up to 30 or 35 em. of mercury. It is controlled either by hand or by motor, and the flow may be regu- lated from 2 or 3 cc. a minute, or less, up to 50 ce. and more. 1 Carrel and A, Hartmann: Journ. Exper. Med., November 1, 1916. 2 du Noiiy: Journ. Exper. Med., November, 1916; May, 1916; April, 1919. ’ Carrel, du Noiiy, Carrel: Journ. Exper. Med., August, 1917. See also: Tuffier and Desmarres: Journ. Exper. Med., February, 1918. PROCEEDINGS 123 A new form of the Mohr’s specific gravity balance for small quantities of liquids. P. LecomtTr pu Noty. This balance gives the 7; of a milligram by the means of a rider. The plunger being about 1 cc., the numbers read on the weights indicate the density of the liquid tested, if the apparatus has first been standardized with water. An apparatus for measuring rapidly and accurately the surface tension of all liquids. P. LecomtTs pu Noty. It is based upon the well-known adhesion principle, of a disc or ring or square, brought into contact with the liquid. Thetension is measured by the torsion of a wire, which torsion is simply read on a dial. The behavior of the centriole and the centrosphere in the degenerating fibroblasts of tissue cultures. WARREN H. Lewis. In the normal healthy fibroblast the centriole lies close to one side or one end of the nucleus. The mitochondria do not appear to have any definite relation to it since they are arranged more or less parallel to the long axis of the cell. A few scattered granules are usually present. As degeneration progresses the granules increase In number and tend to accumulate about the centriole. As the process goes on the accumula- tion of granules about the centriole increases and each granule usually becomes surrounded by a vacuole. Coincident with this accumulation of granules, the mitochondrial threads and rods become more or less radially arranged about the cen- triole. Asthe number of vacuoles and granules increases there develops about the centriole a clear area, the centrosphere, which gradually increases in size and may become as large as the nucleus. The centro- sphere is usually quite free from granules, vacuoles and mitochondria. Protoplasmic strands, in which the mitochondria lie, extend from the centrosphere toward the periphery and often give a radial arrangement . as the vacuoles. As degeneration proceeds the mitochondrial threads often break up into short rods and granules which may change into vesicles. The small degeneration vacuoles and granules often exhibit quite active movements different from and more extended than the ordinary mitochondrial movements. The direction is from the region of the centriole or centrosphere to the periphery of the cell or vice versa. Are such movements due to cytoplasmic currents or to the metabolic inter- changes between vacuoles or granules and the cytoplasm? The orientation of the various structures about the centriole and centrosphere in degenerating fibroblasts suggests that the centriole and not the nucleus is the center of metabolic activity of the cell, the dynamic center of the cell according to Boveri. This increase in the size of the centrosphere is probably a compen- sating reaction on the part of the cell induced by an upset in the normal metabolic balance between centriole and periphery through the accu- mulation of granules and vacuoles. 124 AMERICAN PHYSIOLOGICAL SOCIETY A comparison of the influence of secretine and the antineuritic vitamine on pancreatic secretion and bile flow. CARL VOEGTLIN and C. N. Myers. An alcoholic extract of dried brewers’ yeast, after being submitted to the same purification as described for the preparation of Funk’s vita- mine fraction, causes, when injected intravenously, a marked increase in pancreatic secretion and bile flow. Extracts of the mucosa of the duodenum prepared in the same manner still possess their characteristic action on pancreatic secretion and also relieve the paralytic symptoms of polyneuritic pigeons. Later experiments by Voegtlin have furthermore shown that liver, heart muscle and milk also contain a substance which stimulates pan- creatic secretion and increases the flow of bile. The presence of the antineuritic vitamine in such extracts had been previously demon- strated. Hence it is concluded that secretine is not only located in the intestinal mucosa, but also in at least two other organs of the body. The failure of previous workers to extract secretine from these organs is probably due to the use of improper chemical methods. From these and other observations it is concluded that secretine and the antineuritic vitamine are very closely related, if not identical. Electric conductivity in relation to shock and exhaustion. GEORGE W. CRILE and HELEN R. HosMER. In previous researches histologic and clinical findings have indicated that in exhaustion and shock there exists an apparent synthetic relation- ship between certain organs—notably the central nervous system and the liver. The work of Lillie, Osterhaut and Galleotti and other bio- physical chemists suggests that further evidence of the réle of these organs in exhaustion and shock might be secured by measurements of their electric conductivity. The research of which this paper presents a preliminary report was therefore undertaken, the first measuremi*:ts being made by Capt. G. B. Obear of the Case School of Applied Sc:eace, and the work continued by Miss Helen R. Hosmer. Electric conductivity measurements of 107 rabbits have been made. This number includes 24 normal rabbits .nd groups of at least 6 rabbits, each of which were subjected to exhaustion from each of the following causes: prolonged insomnia, surgical shock, fright, infection, adrenalin injection, thyroid feeding, hydrochloric acid injection. We have studied also the effect of sleep and rest for different periods, of morphin alone and in the presence of infection, of prolonged ether anesthesia, of prolonged nitrous oxid-oxygen anesthesia. These preliminary studies, a, have shown consistent antithetic changes in the brain and the liver; i.e., in every type of exhaustion-the electric conductivity of the brain was decreased below the normal and the conductivity of the liver was increased above the normal; 6b, have indicated a general range of electric conductivity of the various organs and tissues. PROCEEDINGS £25 In general, like changes under the same conditions were observed in the cerebrum and the cerebellum—these changes being most marked in the cerebellum. This finding is consistent with our observations of the comparative histologic changes in the cerebrum and cerebellum produced by exhaustion from the same causes. The dependence of respiratory activity wpon. conditions in the central mechanism. F.H. Pike, Haten C. Coomss and A. Barrp HAsTINGs. While respiratory activity may be automatic under certain condi- tions,! it is almost certainly not wholly automatic under the ordinary conditions of life. Afferent nerve impulses affect not only the frequency of the respiratory movements, but also their form. In this latter func- tion the vagus and the afferent roots of the spinal nerves enter into the problem. We strongly support Baglioni’s? contention on this point. The functional relation of the dorsal roots of the thoracic nerves to the efferent roots to the intercostal muscles may be regarded as merely a special phase of the wider functional relations of afferent to efferent roots as set forth by Sherrington. We have shown that strychnine convulsions of the respiratory muscles fail after section of the dorsal roots of the thoracic nerves, just as they fail in the skeletal muscles generally after section of the afferent spinal root.’ Other factors, generally considered to be related to the concentration of the hydrogen ions in the circulating blood, enter into the problem. The regulation of the respiration becomes at bottom a problem of the conditions and manner of stimulation of the nervous elements of the central respiratory mechanism. It has been shown‘ that restriction of the volume of blood flowing through the medulla oblongata increases the minute volume of the respiration. We have shown that there is also a reduction in the total carbon dioxide of the blood plasma. Hyperp- noea, or even dyspnoea, follows partial or complete occlusion of the four cerebral arteries in the cat, and the concentration of the carbon dioxide in the plasma falls rapidly. Restoration of the cerebral cir- culation is followed by a prompt cessation of the hyperpnoea and a rise in the carbon dioxide of the plasma.° The changes in respiration on partial or complete occlusion of the cerebral arteries are opposite in direction to what one would expect if the change in the concentration of carbon dioxide and the related change in the concentration of the hydrogen ions were the only factors con- cerned. We can see no obvious source of large quantities of acid in these experiments, and we are not convinced that a low concentration of carbon dioxide in the blood is an unfailing indication of acidosis. 1 MacDonald and Ried: Journ. Physiology, 1898, xxiii, 100; Stewart and Pike: This Journal, 1907, xix, 328; Winterstein: Arch. f. d. gesammt. Physiol., Cxxxvili, 159. 2 Baglioni: Zur Analyse der Reflexfunction, Wiesbaden, 1907. 3 Moore and Oertel: This Journal, 1899, iii, 45. 4 Geppert and Zuntz: Arch. f. d. gesammt. Physiol., 1888, xlii, 218. 5 Proc. Soc. Exper. Biol. and Med., 1919, xvi, 49. 126 AMERICAN PHYSIOLOGICAL SOCIETY A consideration of our experimental data leads us to the conclusion that it is not merely the condition in the circulating blood, which Hal- dane emphasized, but also the set of conditions in the medulla oblongata itself, dependent upon at least four different factors, which determines the degree of respiratory activity. It is our present view that respira- tory activity is regulated in such a way as to maintain the usual or nor- mal set of conditions as nearly constant as possible. The activity of the respiratory mechanism during the restriction of blood flow through the medulla is independent of any known antecedent change in the group of afferent nerve impulses and, to this extent, is automatic. But in the normal action of the central mechanism of respiration, there is a sum- mation of all the various forms of stimulation, chemical and nervous, by the nerve cells present therein. Observations on decerebrate cats. Lois Fraser, R. 8. Lane and J. J. R. MAcLEop. It has been shown by one of us that the respiratory volume remains fairly uniform for three or four hours in most decerebrate cats after the effects of the initial etherization have passed off. Hyperpnoea usually develops later and this is accompanied by a depression in the alveolar CO, percentage and a lowering of the arterial blood carbonate. In the present investigation it was intended to study the effect produced by causing the animal to breathe through valves into a closed system of wide-bore tubing provided with soda-lime absorption bottles and a Gad- Krogh spirometer. The object was to find the exact degree of oxygen deficiency at which increased pulmonary ventilation would supervene, and to seek for evidence as to whether this hyperpnoea is associated with changes in the alveolar air (R.Q.) and blood (arterial-blood CO: + PH) that could be attributed to the appearance in the organism of unoxidized acid. Although a sufficient number of data has not as yet been collected to answer these questions, the interesting observation has been made that a decided hyperpnoeadevelops a few minutes after connecting the animal with the respiration tube and spirometer. The evidence of this hyperp- noea is obtained partly by observing the tracing produced by the spirom- eter, or by a tambour connected with the tracheal tube before the valves, and partly by analysis of the alveolar air. The results with the latter have invariably shown a decrease in the percentage of CO, and a decided rise in the respiratory quotient, while the oxygen in the inspired air is still well above 15 per cent. Similar results were obtained in two experiments in which an excess of oxygen was added to the system before causing the animal to respire into it. There can be no doubt that the slight resistance offered to expiration has served to increase the excitability of the respiratory center. This may be due to afferent stimuli set up either by the more distended condition of the alveoli (acting on the center through the vagi) or by the distended condition of the thoracic walls (acting through the mee nerves). The following figures will serve to illustrate the results. PROCEEDINGS 127 wenimen or | Marmanony votewerecvste| nesprnazony qvorraye _ |0+ PERCENTAGE 1 ERD RIAN ||) ea Dp A eg red os 8 De dt DURING Before During Before During UE SISEN EOS XXIV 1080 1845 0.82 1.63 14.4 XXVIII 600 1200 0.69 1.58 15.34 XXVI 905 2000 0.85 1.02 W525 XXIX 1120 2250 0.85 1.27, Dy; Changes in hydrogen ion concentration in the sweat and urine following exercise and heat. GEORGE A. TALBERT. Data were presented in support of the following conclusions: 1. That intense exercise of only twenty minutes duration will increase the acidity of the urine. 2. That heat produced in a sweat cabinet will in a large majority of cases increase the acidity of the urine of the subject. 3. That the sweat of man whether produced by exercise or heat is most invariably acid. 4, That heat sweat is always more acid than work sweat. The effect of shattered hemoprotein on the colorless blood corpuscles. CLYDE BROOKS. A protein substance has been isolated from the blood fibrin of the ox which though there is no toxic action produces an artificial leucocytosis. This substance is prepared by the methods previously outlined! The main purpose has been to separate the protein from the blood without destroying the labile molecules which are apparently active in producing the leucotonic action. These labile molecules may be enzymes, vita- mines or various adsorbed bodies which might cling to the fibrin as it is first coagulated. When this protein is injected intravenously or intramuscularly it induces an artificial leucocytosis. There is no apparent preliminary sinking of the number of polymorphonuclear leucocytes immediately following the injection, but a steady upward trend. After several hours new or young leucocytes, and also atypical leucocytes appear in the blood stream, very much as after the injection of typhoid vaccine.’ There is no reaction (chill followed by elevation of temperature, etc.) following the injection of the protein. On the relation between the velocity of Beta rays from radium and their physiological effect. ALFRED C. REDFIELD. The physiological effects upon the eggs of nereis of homogeneous groups of Beta rays of different velocities are proportional to their ability to ionize air. Beta rays of low velocity produce a greater amount of physiological change than the same number of rays of high velocity. 1 Science, February 23, 1919; N. Y. Med. Journ., March 15, 1919. ° 2 Cowie: Arch. Int. Med., 1919; Journ. Amer. Med. Assoc., April, 1919. 128 AMERICAN PHYSIOLOGICAL SOCIETY These conclusions are consistent with, but do not prove the view that the physiological effects of radiations from radium and x-rays are due to the production by them of an ionization of protoplasm. The concentration of alcohol in the tissues of hens after inhalation. T.M. CaARPENTa2R and E. B. Bascock. Hens weighing about 2 kilos were placed in a 216 liter air-tight chamber saturated with alcohol vapor over periods varying from two to twenty-nine hours. The carbon dioxide was absorbed by partially slaked lime and oxygen was supplied from a well counterpoised spirom- eter connected to the chamber. The activity of the individual hens was registered by the method devised by Benedict. The animals were killed immediately after exposure and the alcohol distilled from the various tissues and determined by the Nicloux method. The amounts of alcohol per gram of the whole body and length of exposure are given in the following table: Alcohol in hens after inhalation of its vapor (Milligrams of alcohol per gram of whole body) HEN HOURS ALCOHOL HEN HOURS ALCOHOL HEN HOURS ALCOHOL NUMBER EXPOSED |PER GRAM|| NUMBER EXPOSED |PER GRAM!| NUMBER EXPOSED |PER GRAM 42 16 0.03 10 273 0.64 11 153 2.19 37 2 0.06 29 16 0.81 13 154 2.24 38 2 0.18 46 16 eas 3 153 2.26 39 2 0.20 33 8 1.38 44 16 2.35 25 3 0.25 24 8 iss! 35 4 2.43 21 4 0.27 40 16 1.68 9 29 2p. 5 164 0.28 34 4 lei3 45 163 PATH 43 164 0.38 48 16 1.98 8 29 O20 41 16 0.34 47 16 2.06 6 29 5.67 36 4 0.38 15 8 2413 Hens 5 and 10 were very active practically the entire time during their stay in the chamber. Hens 40 to 48 were stimulated to activity intermittently with varying degrees of success by means of leads from an induction coil. All hens containing more than 1.5 mgm. of alcohol per gram of body substance showed signs of intoxication. The relative concentration of alcohol of different tissues of 12 hens was on the average as follows: BLOG 35 Sie aisles ss peloton Han oR sae Sede has i ee Oe ee 100 Heart 'and lun gsivacs.. isc orci re aie odes ee ee A ee 86 BB BAM GS oe ya acs. chape aks cals ae eee eee ee a eee 84 Mirdneye. so .. fs. USUI. aR RE ES, BLOG sar 79 Alimentary ‘tracts. +. 2ive: eel bailens of aled oii des ee eee Bae 78 Muscle xe isci'h correo eee heise ee nee ae eee 78 BOLO he ccc she says, «ainee Wis hy Rahn aa eet ioe oe ecw aLIe cin he OL a eae 75 DIVOEL Peale cine Ke a Sacer Ae oe AT REN YOR tag One LE 72 ‘SII Ga at eae aoe a ee OA Bie Tas aca On ri MAE LEA Ie hen oe 56 PROCEEDINGS 129 Three dead hens placed in the chamber for sixteen hours gave 1.15 to . 1.22 and 2.09 mgm. of alcohol per gram. Diffusion through the skin played a réle in the experiments with live hens as well as inhalation. The metabolism of bile acids. M.G. Fostar, C. W. Hooper and G. H. WHIPPLE. Very little work has been reported recently dealing with the bile salts, for the methods of analysis available are not only inexact but very labori- ous. Many substances present in bile are knawn to interfere seriously with the various published methods for bile acid determination. It is generally accepted that dog’s bile contains only taurocholice and tauro- choleic acids with, at the most, only a trace of glycocholic acid. The presence of 10 per cent glycocholic acid in the bile acid fraction will not modify the figures computed as taurocholic acid by our method. A new method has been devised which consists in simple hydrolysis of mucin-free bile with sodium hydrate at the temperature of boiling water. Taurocholic acid is completely split into taurine and cholic acid. The taurine is estimated by the Van Slyke amino nitrogen tech- nique, as we have found that taurine gives up all of its amino nitrogen in three minutes. By this method taurocholic acid, added in known amounts to bile, can be quantitatively recovered. Other substances known to be present in bile do not interfere with this method, which has an error not exceeding 6 to 8 per cent. All observations were made upon bile fistula dogs which were.in a nor- mal condition of activity, weight and appetite. These dogs were kept on a careful routine of diet, exercise and bile collection. Six-hour col- lections were made daily with a thirty-minute period of preliminary drainage of the bile fistula. Like many other workers, we observed great variations in the excretion of bile acids in these bile fistula animals, but we found it possible to reduce these fluctuations in large measure by diet control. During fasting periods, these dogs approach a uniform level of bile acid elimination, but even in such periods there are fluctua- tions which we cannot explain. The eliminationfrom hour to hour dur- ing the day is fairly uniform for any given dog, but the daily output may vary agood deal. Asarule the bile acid excretion is a little higher in the forenoon than in the afternoon. Diets rich in meat proteins raise the level of bile acid output to a maximum, and periods of fasting will depress the bile acid output, not to zero, but to about 25 to 35 per cent of this maximum. Sugar feeding will depress the bile acids below the fasting level of excretion. It is evident that there-is an endogenous as well as an exogenous source of bile acids. After periods of fasting, a diet rich in meat proteins will not lift the bile acid output to the usual maximum level, and may raise it scarcely at all for several days. This may indicate a deviation of cer- tain food elements from bile acid formation to tissue protein construc- tion. This is only one of many suggestive points which seem to indi- cate an important relationship between the body protein metabolism and the bzle acid metabolism. THE AMERICAN JOURNAL OF PHYSIOLOGY, VOL. 49, No. 1 130 AMERICAN PHYSIOLOGICAL SOCIETY Small amounts of bile given by mouth show a prompt excretion of the contained bile acids within three to four hours. If not over 2 grams of taurocholiec acid are given by mouth, we may expect about 90 per cent elimination in the bile within four hours. Large amounts of bile acids given by mouth may prolong this elimination over many hours or even days and the cholagogue action may last even longer than the increased bile acid excretion. By giving sugar with bile acids by mouth, the cholagogue action can be inhibited and a maximum concentration of bile acids in bile (7 to 9 per cent) may be attained in this way. Bile given at night in moderate amounts has no influence upon the bile acid output of the following day. Bile exclusion by means of a night ab- dominal binder to prevent any licking of the fistula does not modify the curve of bile acid elimination in our experiments. This holds for all diet experiments as well as for periods of fasting. Taurine intravenously or by mouth does not influence bile acid elimination. Taurine plus cholic acid by mouth reacts exactly as does taurocholie acid and causes a cholagogue action with great increase in output of bile acids. Cholie acid alone gives a cholagogue action and with a rich nitrogen diet causes a great rise in bile acid output. This is not true during fasting periods and we must assume that this increase in bile acid production is limited by the amount of available taurine either from food or tissue protein. Cystine injection alone does not influence bile acid excretion but combined with cholic acid feeding reacts exactly as does taurine. This confirms other work to show that taurine is derived from the amino acid cystine. Cholic acid is of unknown origin in the body. It gives certain chemi- eal reactions like cholesterol, turpentine and camphor. Cholesterol feeding and the feeding of large amounts of red blood cells did not influence the output of bile acids in bile. Intravenous injection of large amounts of laked red blood cells was also negative. Feeding terpene hydrate and camphor alone or combined with taurine gave no positive results. Casein, caseinamino acids, beef extract (commercial) and gelatin feeding have no influence upon the bile acid excretion. Our experiments seem to indicate the derivation of cholic acid either from certain meat proteins in the food, or from the tissue proteins, or both. Cholic acid is normally the limiting factor which determines the level of bile acid excretion in bile fistula dogs. On the compensation of ocular and equilibrium disturbances which follow unilateral removal of the otic labyrinth. Demonstration! ALEXANDER L. PRINCE. The ocular and equilibrium disturbances ‘which follow unilateral — destruction of the otie labyrinth in higher vertebrates are of short duration and are ascribed to the unbalanced activity of the intact labyrinth. In the cat, these disturbances consist of deviation of the lee enor CE these experiments appeared in the Proc. for Exper. Biol. and Med., Jl/, xiv, 30. * Wilson and Pike: Phil. Trans. Royal Soc., London, 1912, Series B, eciii, 127. PROCEEDINGS 131 eyes toward the side of the lesion, accompanied by nystagmus, and of a tendency to roll, fall and execute circus movements, also in the direction of the injured side. These symptoms gradually diminish in intensity and have disappeared within forty-eight to seventy-two hours after operation. The question arises as to the mechanism concerned in the. disappear- ance of the disturbances occasioned by the removal of the labyrinth. In the animals demonstrated, decerebration was performed, several weeks after complete recovery from the effects of the labyrinthine operation, by section of the brain stem just anterior to the corpora quadrigemina. This procedure is immediately followed by deviation of the eyes to the side of the lesion and recurrence of the symptoms of disturbed equilibration. In view of these observations, the disappearance of the ocular and equilibrium disturbances following unilateral removal of the labyrinth is attributed to the activity of a compensatory mechanism. The nervous paths concerned in the process of compensation may be roughly localized in the cerebrum above the level of the corpora quadrigemina. A new type of rebreather. Demonstration. Caru N. LARSON. To obviate the immobility of the Henderson-Pierce rebreather the capacity of which is controlled by intake and outlet of water (requiring water and sewer connections) a new type of rebreather has been devised and installed in the Medical Research Laboratory of the Air Service, War Department. The new form is light and portable, it is free from water system connections, it can be graduated so that the oxygen per- centage of the inclosed air is known at every moment and checking gas analyses can be made at any moment during the progress of a test. The rate and volume of the respirations and of the oxygen consumption can be taken directly by the automatic recorder devised by the author and from the table of constants of the instrument. A brief description of the new features of the machine is as follows: The air chamber is of two pieces suitably framed and supported. The lower piece is a double cylinder with common base and open at the top. Each is 15 inches high and the inner cylinder 14 inches in diameter. Free Geid —-—-— Formo/ /20 90 ‘ as Pe atten tite Ad “Wen” ey PONS ‘ - . “~ at = id So ates 60 i 4 / ‘ ¢ 30 Bs, ae eee ee — eee eS OS er eae 2 3 Hours GASTRIC RESPONSE TO MEATS = 5 Rump ° Steak Rare Total Qed ----- Free Ged —--— — Formol Joa Rump Steak C . wD, NaOH oS Total Qeid -=--- Free Ged —-—-— Formo/ 187 188 FISHBACK, SMITH, BERGEIM, LICHTENTHAELER, ET AL. Joa 7. Sirloin wW.D M a 0H ce Total Geid ----- Free Qed 120 ----— Formol 8. Joa N. +5 Na OH Tele! Ged = Tenderloin ec ----- Free Gerd Uy ) Formol Steak . Med N NaOH ce GASTRIC RESPONSE TO MEATS Joa Tender/oin Steak 7 e Planked Med Tefal Gerd woe FreeAc/d se Foro! 189 fNa0H e¢. 120 90 Tri fers 10. wD. Total Qed wore Free Qod —-—-— Formo/ peownn-enrr --—- ee oe Sey 190 FISHBACK, SMITH, BERGEIM, LICHTENTHAELER, ET AL. steaks. These latter were prepared by the chef of a high grade restau- rant and were of course far more appetizing in appearance and taste as well as more tender than the others. That the cost of the different cuts of beef bears no relation to nutritive value has been shown particularly by Hall and Emmett (13). Cost is dependent upon such considerations as tenderness, grain, color, general appearance and convenience of cook- ing. According to the authors cited, the choice portion of beef forming about one-fourth its total weight represents nearly one-half its retail cost. From the standpoint of protein and energy, the cheaper cuts were found to be as valuable and in some cases more valuable than higher-priced cuts. Tri ‘ Tenderlom Steak hi: . w.d Total Aeid eee Free Ged == Formo/ It is fortunate that our stomachs also give favor to the cheaper cuts of beef by digesting them more easily than expensive cuts. A typical comparison between roast beef and these steaks is obtained from figure 12. It will be seen that roast beef leaves the stomach sooner than ten- derloin but more slowly than a rump steak. Hamburger steaks. That a hamburger steak remains in the stomach about the same length of time as an equal amount of roast beef is illus- trated by a comparison of these with the same individual (see figs. 3, 4 and 13). It may be that hamburger is handled a little more easily than roast beef but the difference is very slight. GASTRIC RESPONSE TO MEATS 191 aay i 12 e Roast Beef Rare NaOH se Total Acid -----Free Acid 1a = For mol Ri Chuck Hamburg w.D, Total Acid =a Free acid 192 FISHBACK, SMITH, BERGEIM, LICHTENTHAELER, ET AL. Stewed beef. Figures 14, 15, 16 and 17 show comparisons between roast beef and stewed beef on the same individuals. In one case the stewed beef left the stomach the sooner while in the other case the reverse was true. In one case the acid stimulation was greater with roast than with stewed beef. Apparently the response of the stomach to stewed beef is not much different from that to roast beef. Corned beef. Boiled corned beef shows little difference in gastric response from that of roast beef or stewed beef. Evacuation times are about the same. The boiled meats appear, however, to be somewhat less active in stimulating secretion as the rise in the curve is usually somewhat delayed. This may be due to loss of extractives. Compare figure 18 with figures 3 and 4 and figures 19 and 20. Dried beef. In the case of dried beef 70 grams were fed instead of 100 grams on account of the high solid content of this form of beef. Dried P beef appears to be about as digestible as ordinary roast beef, but the lack of moisture where no water is taken with the meat appears to delay slightly the onset of digestion. See figures 21 and 22 for a comparison of dried and roast beef on a subject of the rapid type. Beef bologna, calves’ liver and beef tongue. Beef bologna was found in two cases to be digested in practically the same time as roast beef (see figs. 23 and 24). Calves’ liver required a slightly longer time to leave the stomach than roast beef or dried beef. This is not in agreement with the finding of Beaumont (compare figs. 22 and 25). Boiled tongue was found in a single case to take over 44 hours as compared with 32 hours for dried beef. _ Frankfurters, sweetbreads and tripe. Beef frankfurters left the stomach rather more quickly than most of the other forms of beef. For example, 80 grams of boiled frankfurter left the stomach in 2} hours in one ease (fig. 26) as compared with 23 hours for 100 grams of roast beef (fig. 27). Calf sweetbreads required 2} hours to leave the stomach in our test, thus belonging to the class of more rapidly moving meats (see fig. 28). The so-called “honeycomb” tripe left the stomach a little more slowly than roast beef (see figs. 29, 30 and 31). The gastric digestion of tripe did not appear, however, to differ materially from the digestion of other beef products. GASTRIC RESPONSE TO MEATS 193 & 14. Stewed Bee f 2 a0 ec —- hal Acid ----- Free ded (EG), hte Formo/ 90 60 7 v +-- SSS SSN 30 yy ss Y jer ae —~ P pee ~~... come ier ore isa Pe A es EEE > r Pa 7} A 3 Hours We LS. Roast Beef w.D. NaOH ce, Total Aoid Free Qed meme — Forme! 194 FISHBACK, SMITH, BERGEIM, LICHTENTHAELER, ET AL. N X NaOH Ral et ss Roast Beef /50 Med, Total Ged ----- Free Acid 3) Formo/ Ral a Te Stewed Beef M 20H ec —- Fofal Qed +---- Free Geid Se ee GASTRIC RESPONSE TO MEATS 195 ni tS» Corned Beef oem pTolal (Berd: moan Free Acid 150 a.eve For mol N ‘ A HaOH ec (XO 90 60 30 te ae tie — seen Wal Corned Beef Jk —— Tofal Gerd a~--- Free Geid 151 =.-- Forme! N. Zp Na0H ce 12 TS ee yysolids b 60 30 eens, . Oe en gs ee es 196 FISHBACK, SMITH, Wal Round Steak Broiled ——— Ttal Acid Formol Gra Dried Beef W NaOH ____ Tefal deid Se lh as Free Gerd —.—-e For mol 20. Zi BERGEIM, LICHTENTHAELER, ET AL. - ——eee Hours easel GASTRIC RESPONSE TO MEATS 197 Qroa | oie on. ™Med Tefal Qed id Free Qeid — = — Formo! MN panos Cru O35 Roast Beef iy /50 Rare Total Qed =---- Free Ged 12 —---— Formol 90 60 30 198 FISHBACK, SMITH, BERGEIM, LICHTENTHAELER, ET AL. e 2H. Beef Bologna M NaOH Total Geid sty - ----Free Ged 150 —-—-— For mol/l /20 90 60 ‘ a 3 Hours MlacH Qra Es Calves hiver 7 5 Fried 3 120 Tota! Qed Free Gerd —-—-— Formo/ Hours 3 GASTRIC RESPONSE TO MEATS 199 GI 2b Frank furters : “NaOH i! Aeid es Ce | wien Free Aad N. 4 a 0H ee 1A / a Hours Gl Roast Beef Z a, Rare Noon" Total Ged ~ —— Fermol 200 FISHBACK, SMITH, BERGEIM, LICHTENTHAELER, ET AL. Spk Sweetbreads 2 8. Total Acid (0) | ee Tree Acid / a Hours Tres Tripe 2 q. a Free Acid —-=-— Formo! 4 a ] Hours GASTRIC RESPONSE TO MEATS 201 Oo ie 30. a NaOH ec Total cid Sein ent Free acid 1 —-=—:— Formo/ Total Qed wence Free Gad 120 90 ~~ eS at a et 60 30 THE AMERICAN JOURNAL OF PHYSIOLOGY, VOL. 49, No. 2 202 FISHBACK, SMITH, BERGEIM, LICHTENTHAELER, ET AL. SUMMARY AND CONCLUSIONS The digestion of various forms of beef and beef products in the normal human stomach was studied by the fractional method. Over seventy complete experiments were made on twenty-five different subjects. It was found that all normal stomachs do not respond alike to the entrance of the same food. Some respond very promptly and decidedly to the entrance of food, whereas others respond very slowly and indifferently to the same food. Also one type of normal stomach empties very quickly whereas a second type evacuates slowly under like dietary condi- tions. The average results for individuals of the rapid- and slow- emptying types have been tabulated (see table 4) and typical com- parisons of different meats or different modes of cooking have been illustrated by curves showing acidities developed and emptying times. Roast beef appeared to be handled by the stomach with about the same ease whether rare, medium or well-done, although the rare beef had perhaps a slight advantage in this respect. Beef steaks appeared to be just as readily digested if cooked rare as if medium or well-done. Very tough steaks from the cheaper and tougher cuts of meats such as rump and shank showed distinctly more rapid evacuation than sirloin or the best tenderloin steaks, in the same individuals. Roast beef was found to lie between these two classes of steaks in gastric response and evacuation time. Hamburger steaks were found to leave the stomach in about the same time as an equal weight of roast beef under the same conditions. Stewed beef was handled by the stomach in practically the same time as roast beef, but with a less rapid development of acidity. The response to boiled corned beef was similar to that of roast beef or stewed beef. Acid productions may, however, be slightly delayed in the case of corned beef. Dried beef was digested with almost the same ease as ordinary roast beef. There may be a slight delay due to the low moisture content if the meat is eaten dry. Beef bologna was handled by the stomach in the same length of time as roast beef. Calves’ liver required a slightly longer time. Beef tongue was less readily digested than dried beef. Frankfurters left the stomach rather quickly, as did also sweetbreads. Tripe was digested a little less rapidly than roast beef. For 100 grams of the beef products tested an average evacuation time of 2 hours and 35 minutes was obtained on subjects of the rapid- GASTRIC RESPONSE TO MEATS 203 emptying type and of 3 hours and 25 minutes on subjects of the slow- emptying type. Total acidities as high as 184 were obtained on meats. The average total acidity at the height of digestion was in the case of beef products 120. These high acid values regularly shown by normal men necessitate a revision of older ideas of ““hyperacidity.’’ The amino acid nitrogen values (which include ammonia) are moder- ately high at the beginning of digestion due to the ammonia of the meats, show a secondary rise as digestion proceeds and fall to a low level at the end of digestion as the soluble products leave the stomach. Pepsin values attain their highest point toward the end of digestion. The authors wish to express their appreciation of the codperation of the students of Jefferson Medical College, who kindly acted as subjects of these tests. BIBLIOGRAPHY (1) Beaumont: Physiology of digestion, 2nd Ed., 1847, Burlington, Vt. (2) Jessen: Zeitschr. f. Biol., 1883, xix, 129. (3) PenzoupT: Deutsch. Arch. klin. Med., 1893, li, 535. (4) Bercem, Reuruss anp Hawk: Journ. Biol. Chem., 1914, xix, 348. (5) Cartson: This Journal, 1915, xxxvil, 70. (6) Zunz: Internat. Beitr. Path. Therap., 1910, ii, 372. (7) CHRISTIANSEN: Biochem. Zeitschr, 1913, xlvi, 24. (8) Caruson: This Journal, 1915, xxxviii, 248. : (9) Hoaauanp, McBripr anv Powicx: U.S. Dept. Agric., Bull. 433, 1917. (10) Faux anp McGuire: Journ. Biol. Chem., 1919, xxxvii, 547. (11) Fowier: Unpublished data from this laboratory. (12) GrinpLey, MasoNnNiIeER AND Porter: U.S. Dept. Agric., Bull. 193, 1907. (13) Hauu anp Emmett: Ill. Agric. Exper. Sta. Bull. 158. GASTRIC RESPONSE TO FOODS! IV. Tue RESPONSE OF THE STOMACH TO PoRK AND PoRK PRopUCTS CLARENCE A. SMITH, HAMILTON R. FISHBACK, OLAF BERGEIM, MARTIN E. REHFUSS anp PHILIP B. HAWK From the Laboratory of Physiological Chemistry, Jefferson Medical College, Philadelphia Received for publication April 22, 1919 This study on the digestion of pork and pork products is one of a series (1) of studies on the response of the human stomach to various foods. There are comparatively few investigations that bear directly on the gastric digestion of pork and its products. Beaumont (2) gives the following results for the evacuation time of pork products, the tests being carried out on the subject, Alexis St. Martin. Roast beef values of the same investigator are given for comparison. TABLE 1 Digestion time of meats in the human stomach (Beaumont) MEAT COOKING HOURS MINUTES IE OTR iy 2 cis Sic Wateng 55s tassios ee Eee Roast 5 15 AUISAIEG: cca ce es he sce oe Me es ene an ErOlLed 3 20 Poe Meets. 24-5 a 4s ode eee eae eR Ouse 1 BCE oj Nereis Rar dio ae Cane Lee || PR Oastara4re 3 IB Oe TE ahs stein adiepas ois Te ee Oe ee Roast well-done 3 30 Jessen (3) on his subject obtained a value of three hours for raw pork as compared with two hours for raw beef. Penzoldt (4) obtained the following values for pork and beef steak on his two subjects. | 1 The expenses of this investigation were defrayed by a fund furnished by Mrs. M. H. Henderson, the Curtis Publishing Company and Dr. L. M. Halsey. 204 GASTRIC RESPONSE TO MEATS 205 TABLE 2 Digestion time of meats in the human stomach (Penzoldt) Ee a SAREE SEULEE CUENTA “SSW AT can REA PRAEGER GIGGLBERGER er CO ENG 100 GRAMS 160 GRAMS hours hours and minutes “LLL hon SS ie sea ra ee Boiled 3 3: 20 amides: . ; too On ee ee ee Raw h 3:46 PEL IRUEA Kons. ne. s ss. cs eases .| EPried warm 5 4:15 (250 gm.) The present series of tests on the digestion of pork and pork products in the stomachs of normal men was carried out in the same manner as the tests on beef described in a preceding article (1). Table 3 gives a summary of the results as to evacuation time and highest total acidities attained for a number of these meats, the results obtained with slow- and rapid-emptying types of stomachs being averaged separately. The results of 31 separate tests on 10 different subjects are recorded. Figures 1 to 24 illustrate the digestive response of the stomach to the various pork products as compared with each other and with the re- sponse of certain types of beef. The comparative tests were made upon the same individuals under as nearly identical conditions as possible and the illustrations given are typical of the results obtained. One hundred grams of meat were fed unless otherwise stated. Pork has usually been considered a rather indigestible kind of meat. In explanation of this it is said that the high proportion of fat between the meat fibers forms a coating which the gastric juice can penetrate only with difficulty. Hence convalescents, or people with digestive disturbances of any kind, are warned to leave all pork products out of their diet. In spite of this fact, however, and in spite of the fact that a great mass of people of the United States abstain from pork on principle, the per capita consumption of pork in this country is estimated at a little more than 88 pounds per year, nearly 10 pounds more per capita than beef, and almost as much as all the other forms of meat combined— including beef. In reality the normal human stomach finds no extraordinary difficulty in digesting pork. It is true that, as shown in table 3, the emptying time of pork averages somewhat longer than that of other common meats, and this relative slowness of digestion applies also to pork prod- ucts. If pork taken with a mixed meal, however, retards stomach digestion appreciably, then it may well be avoided by weak stomachs. 206 SMITH, FISHBACK, BERGEIM, REHFUSS AND HAWK TABLE 3 Gastric digestion of pork and pork products TYPE OF STOMACH Rapid emptying Slow emptying NO. |SUBJECT MEAT ee Evacuation Evacuation time, hours Highest time, hours Highest and total acidity* and total acidity* minutes minutes average average average average 1 | Ara | Roast pork 3:30 108 2 | Cru | Roast pork 2:15 112 3 | Dal | Roast pork’ 2: 00 102 4 | Ev | Roast pork 3:00 |2: 45 | 155 | 119 5 | Wat | Roast pork 3:45 118 6 | Wr | Roast pork 3:30 160 7 | Spn | Roast pork 3: 45 |3: 45 | 120 | 130 8 | Spn | Roast pork (250 grams) 5: 30 |5: 80] 145 | 145 9 | Oa _ | Sausage 2:45 |2:45 | 104 | 104 10 | Gl Sausage 3:15 108 11 | Fal | Sausage 2:45 |3: 00; 104 | 106 12 | Joa | Ham, fried 3:00|3:00|} 65 | 65 13 | Wal | Ham, fried 4:15 /4:15]| 150 | 150 14 | Bos | Ham, boiled 3:15 |3:15| 187 | 137 15 | Kru | Ham, boiled 3: 00 |3: 00} 140 | 140 16 | Km | Ham, minced 2:00 |2:00) 115} 115 17 | Bos | Ham, minced 3:00 |3: 00 | 120 | 120 18 | Mes | Ham, baked 4:15 118 19 | Ra | Ham, baked 3: 45 |4: 00 118 20 | Joa | Ham, bologna 3:15 |8:15| 68] 68 , 21 | Wel | Bacon, fried 4: 30 4:30] 115 | 115 22 | Gl Pigs’ feet, soused 3:45 120 23 | Ca | Pigs’ feet, soused 2: 30 |3: 15 | 135 | 125 24 | Ara | Liver and bacon, fried |3:00| - 94 25 | Bos | Liver and bacon, fried |2:30 |2:45 | 137 | 116 26 | Kru | Liver and bacon, fried 3: 30/3: 30| 125 | 125 27 | Wel | Ham sandwich, fried 2:45 |2: 45] 101 | 101 28 | Gl Scrapple, fried 3:45 85 29 | Oa_ | Scrapple, fried 3:45 3:45] 85 | 85 30 | Gl Pork chops 4:00 129 31 | Ca | Pork chops 3: 45 |4:00| 144 | 134 *Acidities are expressed as cc. of N/10 alkali required to neutralize 100 ce. GASTRIC RESPONSE TO MEATS 207 Roast pork. The response of the stomach to 100 grams of roast pork is charted in figure 1. The evacuation time, as shown, was 3% hours. Figure 2 shows the response of another individual to roast pork. By comparing this chart with figure 22 in the preceding article on beef products (1) it will be seen that whereas roast beef required 12 hours to leave the stomach, roast pork required 33 hours. A comparison of the average results likewise shows for the rapid type of individual an empty- ing time for beef of 2} hours and for pork 23 hours, while for the slow- emptying type the periods were 33 hours and 3¢ hours respectively. Thus roast pork requires appreciably longer to digest than roast beef although the differences are not nearly so great as those found by Beau- mont (see table 1). In fact certain individuals appear to handle roast pork very readily; fully as well as roast beef. Compare figure 3 with figure 23 in our paper on beef products showing an evacuation time for pork of 2} hours as compared with 24 hours for beef. Figures 13 and 24 illustrate the digestion of pork chops. Compare figure 24 with figure 4 showing digestion of roast beef and note that practically the same time was required for each. In the same way com- pare figures 13 and 27 in the article on beef (1), noting the markedly longer time required for pork in the case of this individual. Pork chops and roast pork appear to require about the same periods for digestion in the stomach. Fried ham in our experiments required considerably longer to digest than beef (compare figs. 5 and 6, also fig. 20 in the paper on beef products (1)). . A comparison of boiled ham and minced ham may be obtained from figures 7 and 8. The minced ham shows but slight advantage although the acidity is more rapidly developed in this case than where mincing was not employed. Likewise a difference of only fifteen minutes was noted in favor of roast beef as compared with the minced ham or a dif- ference of thirty minutes as compared with boiled ham (see fig. 9 as compared with figs. 7 and 8). The digestion of liver and bacon is illustrated by figures 10 and 11. If figure 10 is compared with figure 22 of the earlier paper on beef products (1), it will be noted that liver and bacon require appreciably longer for gastric digestion than roast beef. Comparisons of liver and bacon with liver alone are shown by figures 11 and 12, and by figure 10 as compared with figure 25 in paper on beef products. It will be noted that from 4 to 1 hour longer was required for the fried liver without bacon in one case while in the other case the bacon slightly prolonged the evacuation time. 208 SMITH, FISHBACK, BERGEIM, REHFUSS AND HAWK Spr i Roast Pork 40 < Total Qed 120 90 60 eas, 30 on AS en ene — saree — - —s ‘ a 3 Hours { ara 2 \ é i Roast Pork —— Tefal Acid =<=== Free Qed R —-—-— Formol! N —---— Pepsin fe Ne0H ec qo 60 - - _——-* ! i yey . ~ _ : 4 = we < pe tte meee ee eee. ——_~ ++ - - eee — 7 age ee eee GASTRIC RESPONSE TO MEATS oe 6) Roast Pork - — = Jalal Aer, Aiiam Free Aeid Sua) Formol # NaOH ec Ca 4} Moast Beef . w.D Wa 0H de ec Total Acid ----- Free derd STG | pee Formal 209 210 SMITH, FISHBACK, BERGEIM, REHFUSS AND HAWK MeOH WD) 5 7 a ce Tefal Ged s l e =a Free Geid Fried Ham \ / —-—-— Formol Wal b Roast Geet Rare —_ Tefal Aeid oacee Free Qcid —-—-— Forme! ae “=e ia SK ¢ = - ¢ Neer wm s - Y a Hours 1 GASTRIC RESPONSE TO MBATS Bil Bos v e mnced Ham A NaOH —— Total Geid ec ----- Free Geid Bos 8 15 Boiled Ham Va0H 70 ae Total Acid ee ec Free Acid 120) 90 60 30 212 SMITH, FISHBACK, BERGEIM, REHFUSS AND HAWK a ie Bee f ‘| ° 2 ™Med. Total Qed Qra 10. Total eid : 7h ee read Liver ¥ Bacon FENaOH cc qo €0 30 7 =] 3 Hours GASTRIC RESPONSE TO MEATS 213 oe PE 15 Aiver and Bacon re : i Ma0H ec Total Qeid 420 = Free Acid 90 60 NNaOH Bos se Calveshiver L2 . Fried 150 Total Qcid ‘df =—-—-—Formol / 2 3 Fiat 4 214 SMITH, FISHBACK, BERGEIM, REHFUSS AND HAWK GI oe Pork Chops N fg Va0H ce Total Qed t +77 -- Free eid 120 = Fermo/ 90 N 2 g ae Total Qed G | /4 /20 90 60 30 / 2 3 Hours GASTRIC RESPONSE TO MEATS 215 = ‘S Fuicod Hem / : | M yy. OH Onn a —— ah der mn) semi Free Gioid 60 ~-—- = Formos __ Hours s Tilal dod ‘ SUE) | a an eS eae CAE) Ham Bologna GO - - —Formae/ ‘ A 3 Hours NaOH lel Me Tetal Qed See Free Aeid Ham Sandwich mmo 216 SMITH, FISHBACK, BERGEIM, REHFUSS AND HAWK ff Ya OH Wel 18. ss ee aes Fried Bacon ----- Free Qeid 4 —-—-— For mo/ a 1B Scrapple Nao Total acid ----- Free Acid 90 -_—-— Formo! 60 30 oan ee aes ee ge GASTRIC RESPONSE TO MEATS 217 ff a0H cs Total Qed O a aaa ed elon Free Qed Ps O. 120) ——'— Formol Scrapple Oa 2] Sausage s N 70 i oH Total decd ----- Free decd y 2 Pecans THE AMERICAN JOURNAL OF PHYSIOLOGY, VOL. 49, No. 2 SMITH, FISHBACK, BERGEIM, REHFUSS AND HAWK NaH eee DS Gl cD enc EA . Pigs’ Feet ER ey Soused Ca Pigs’ Feet 2 a A Soused NaOH To a Total Aeid ----- Free deid Ei 150 —-=-=Formo/ 12 GO 60 30 fe Seen me Ores _ GASTRIC RESPONSE TO MEATS 219 The comparative responses of pork sausage and pork chops are illus- trated by figures 13 and 14. The averages given in table 3 also indicate that the sausage is somewhat more easily handled. Compare also with roast beef (fig. 27) and beef frankfurters (fig. 26, beef article) and note that the beef has an advantage over sausage. A comparison of fried ham with ham bologna is given by figures 15 and 16, little difference being shown as to response. These charts should be compared with figures 5, 6, 7 and 8 in preceding paper on beef products. The results obtained indicate that ham remains in the N ais Total Gerd 2 Le Ca aonee Free Qed Pork Chops 150 —-—-- Rrmo/ stomach somewhat longer than steaks of the tougher cuts and about the same time as a sirloin or tenderloin steak. The slow evacuation of bacon when ingested in as large amounts as 100 grams is illustrated by figure 18. The comparatively slow develop- ment of acidity may also be noted. The high fat content is presumably responsible for these effects. In contrast with this note the fairly rapid evacuation where two ham sandwiches were given (100 grams bread ~ and 23 grams boiled ham) (fig. 17), also the more rapid development of free acidity. The so-called ‘‘scrapple”’ is a preparation made from pork and cereal, whose “habitat”? is more or less restricted to certain localities. The 220 SMITH, FISHBACK, BERGEIM, REHFUSS AND HAWK head and jowls of the pig are sometimes used as well as heart, liver and meat trimming. The cereals used most commonly are wheat flour, buckwheat flour and cornmeal mixtures. That scrapple leaves the stomach rather slowly is indicated by the charts (figs. 19 and 20) as compared with roast beef (fig. 27, beef article), pork chops (fig. 13) and sausage (fig. 14). The greater delay of digestion of “scrapple” as com- pared with pork sausage is shown also by figures 20 and 21. _ Soused pigs’ feet were also tested. In one case the pigs’ feet required practically as long to leave the stomach as pork chops (compare figs. 22 and 13). In the other case the pigs’ feet were digested much more rapidly (figs. 23 and 24). The latter type of response is perhaps the more characteristic. SUMMARY AND CONCLUSIONS A series of studies of the response of the normal human stomach to various pork products prepared in various ways was carried out using the fractional method of gastric analysis. The average results for evacuation times and acidities developed have been tabulated. Com- parative responses of the same individuals to these various products as well as to certain beef products have been charted. For individuals with stomachs of the rapid-emptying type a general average evacuation time for pork products of 2? hours was found. Subjects of the slow- emptying type showed a general average of 3 hours and 40 minutes. The average total acidity observed at the height of digestion was 117. Pork products in general were comparatively slow to leave the stomach as would be expected from their high fat content. The differences were not as great, however, as some figures in the literature indicate. Thus roast pork was retained appreciably longer than roast beef in most instances. Pork chops required about the same period of gastric diges- tion as roast pork. Fried ham also required considerably longer to digest than roast beef. Minced ham showed a slight advantage over boiled ham as to evacua- tion time. Acidities were also more rapidly developed in the former instance. Roast beef was handled somewhat more quickly than either. Liver and bacon required about the same period of digestion as roast beef. In certain instances liver and bacon were handled more readily than liver alone. In one case the contrary was found. Pork sausage was somewhat more easily handled than were pork chops -but less readily than roast beef. eee nS GASTRIC RESPONSE TO MEATS PPA Ham bologna required about the same time to digest as fried ham or as the less readily digestible beef steaks. The evacuation of bacon was found to be slow and low gastric acidi- ties were developed. Ham sandwiches were more readily handled than most other pork products tested. “Scrapple” left the stomach more slowly than pork sausage and be- longs to the less readily evacuated pork products. Pigs’ feet gave variable results but appear ordinarily to be handled more easily than pork chops. The authors wish to extend their thanks to Dr. R. A. Lichtenthaeler who assisted them in carrying out these tests and also to those Jefferson men who sacrificed time and convenience in acting as subjects. BIBLIOGRAPHY (1) Fisapack, SmitH, Berarim, LICHTENTHAELER, REHFUSS AND Hawk: This Journal, 1919, xlix, 174. (2) Beaumont: Physiology of digestion, 2nd Ed., 1847, Burlington, Vt. (83) JESSEN: Zeitschr. f. Biol., 1883, xix, 129. (4) PenzoupT: Deutsch. Arch. klin. Med., 1898, li, 535. GASTRIC RESPONSE TO FOODS! V. Tur RESPONSE OF THE STOMACH TO LAMB AND LAMB PRopwucTS HAMILTON R. FISHBACK, CLARENCE A. SMITH, OLAF BERGEIM, MARTIN E. REHFUSS anp PHILIP B. HAWK From the Laboratory of Physiological Chemistry, Jefferson Medical College, Philadelphia Received for publication April 22, 1919 The present series of tests on the response of the normal human stomach to lamb and lamb products was carried out in the same manner as our experiments on beef (1) and pork (2) products and with a similar object. Beaumont (3) reported on his subject an evacuation time of 3+ hours for roast lamb as compared with 3 to 33 hours for roast beef. Jessen (4) reports two experiments with raw lamb as compared with raw beef and found both to leave the stomach in two hours. In the present paper are reported the results of fourteen tests with roast lamb and other lamb products on several different normal subjects as well as certain tests on beef and pork products for direct comparison. One hundred grams of meat were ingested in each case. The results of these experiments are averaged in table 1. Values obtained for men whose stomachs in general empty rapidly are given separately from the values obtained with men whose stomachs were of the slow-emptying type. The distinction between the two types of stomach is not so marked in the case of lamb products as it is with certain other foods. As the table indicates from 2% to 2? hours were required for lamb to leave the stomach in the one case and 3 to 4 hours in the other. The charts showing the results of fractional gastric analyses in a number of cases where these meats were fed enable us to compare the responses of the same individual to various meats. In certain cases reference is made to preceding papers upon beef and pork products for such comparisons. The acid curves enable us to distinguish between ' The expenses of this investigation were defrayed by funds furnished by Mrs. M. H. Henderson, the Curtis Publishing Company and Dr. L. M. Halsey. 222 GASTRIC RESPONSE TO MEATS 223 certain pathological responses where evacuation is rapid although little acid is secreted and hence little gastric digestion occurs, and a normal type of rapid-emptying stomach where acid secretion is normal and considerable protein digestion takes place in this organ. The digestion of roast lamb is illustrated by figures 1 to 5. The extreme variation in evacuation times of these normal subjects (com- pare, for example, figure 1 showing an evacuation time of 3? hours with TABLE 1 Gastric digestion of lamb and lamb products TYPE OF STOMACH NUM- | SUB- Rapid-emptying Slow-emptying BER JECT ween ————E—E———————————————— time, Roursand | Miehest of! | ge, hoursand| Highest total average average average average 1 Riv | Roast lamb {1:45 114 2 | Ara | Roast lamb (3:15 138 3 | Bos | Roast lamb [8:45 147 4 | Don | Roast lamb [2:30 147 5 | Han | Roast lamb |2:45 |2:45 | 142 | 137 6 | Wel | Roast lamb 3:45 156 7 | Cop | Roast lamb 3:00 | 3:30} 1238 | 140 8 | Cop | Stewed lamb 4:00 -| 122 9 | Ber | Stewed lamb 4:00} 4:00} 150 | 136 10 | Tri | Lamb chops |2:30 |2:30 | 140] 140 11 | Cop |} Lamp chops 3:30 115 12 | Oa Lamb chops WIE sya (00) |) Tlie anes 13 | Hou | Sheep brains 2215 97 14 | Sim | Sheep brains 2:45 |2:30| 73 85 *Acidities are expressed in terms (cc.) of N/10 alkali required to neutralize 100 ce. of sample. figure 3 where the stomach is emptied in 13 hours) is of interest. The subject of experiment 3 is however unusual in this respect. For comparisons of roast lamb with roast beef, observe figure 1 showing an evacuation time of 3? hours and figure 9 in preceding paper on pork products which shows an evacuation time for roast beef of 2? _hours. Also compare figure 3 showing an emptying time of 13 hours with experiments on roast beef with the same individual recorded in preceding paper on beef products (figs. 1 and 2) which show the beef leaving in 2 hours. A more marked difference in favor of roast beef is ———— 224 FISHBACK, SMITH, BERGEIM, REHFUSS AND HAWK “a0H : Bos be Total Qeid fae Srey Roast Lamb 150} —-—-— Formol WN NadH a Qra Tetal Qed P eae Frce Geil Roast Lamb 120 90 £0 30 /20 90 60 30 GASTRIC RESPONSE TO MEATS . 6) Roast Lamb © M va0H Re Talal Acid anne Free Qed 120 —- == Formo/ 90 60 Wel Ly Total Geid as Free Qcid Roast Lamb Ss Fy | oO /A0 90 60 AC e¢ 150 120 90 60 30 FISHBACK, SMITH, BERGEIM, REHFUSS AND HAWK Cop a Total Ged peice eilerd, Roast lamb —-—-— Fermol Total zi Tr : b ee Free eid Lamb Chops Hours GASTRIC RESPONSE TO MEATS 227 Oa 7 "Noon" ¢ hamb, Chops A va0H Hides inn ievico ree Acer. i) ee Formol /20 ee | Qn / 2 Hours 3 ce 8. Lamb Chops N ao Total Geid . 10 ls ta Free deid =: += Forme] 720 70 Fame nen FN 60 228 FISHBACK, SMITH, BERGEIM, REHFUSS AND HAWK mon e 9. Stewedhamb Total Gcid SRS Free Qed ---— Formol 120) 90 Cop 10. Stewed Lamb nN Total Qeid Zoiseon =m == Free Ged — =—-= Formol GASTRIC RESPONSE TO MEATS Bec Dried Beef HIP Total Acid —~--- Tree Bei SSeS te) 229 Oa Total Aad Roast Beef le . —----Free Aad a For mol Rare 230 FISHBACK, SMITH, BERGEIM. REHFUSS AND HAWK shown by figure 2 as compared with figure 22 in article on beef, the latter leaving in 12 hours. A comparison of roast lamb and roast pork is obtained from figure 2 and figure 12 in preceding paper on pork products, the roast pork re- quiring 33 hours digestion as compared with 3} for lamb chops. Roast lamb may also be compared with boiled ham, figure 1 showing evacua- tion time for roast lamb of 32 hours while figure 8 in preceding article on pork shows 31 hours for the boiled ham. As would be expected, - roast lamb (fig. 4, 33 hours) leaves the stomach sooner than bacon (fig. 18 in preceding article on pork showing evacuation time of 43 hours). Anon | Tri MS, Teta! Qeid -=---Fee aed Roast Beef a ey Rare Lamb chops appear to require about the same period of gastric diges- tion as roast lamb (see table 1). A direct comparison of the two on the same individual’may be obtained from figure 5 (roast lamb, 3 hours) and figure 8 (lamb chops, 3} hours). Compare also figure 6, lamb chops, 25 hours, with figure 13, roast beef, 23 hours and also with rump - steak, 2$ hours (figure 10 in preceding paper on beef). Further comparisons of lamb chops with roast beef are given by figure 7, lamb chops, 24 hours and figure 12, roast beef, 3 hours and by figure 31 in beef article, sirloin steak, 3 hours. The same individual shows an evacuation time of 23 hours for pork sausage (fig. 21 in article on pork). Stewed lamb (fig. 10) left the stomach in 4 hours as compared with 35 hours for lamb chops (fig. 8) and 3 hours for roast lamb (fig. 5). In GASTRIC RESPONSE TO MEATS 231 Sim gs fe Sheep Brains Tefal Acid ----- Free Acid Hou 15% Sheep Brains Total Acid i Free Aeid 232 FISHBACK, SMITH, BERGEIM, REHFUSS AND HAWK another case (fig. 9) stewed lamb required the same time as dried beef (fig. 11). Sheep brains left the stomach in moderate time. In one case 23 : hours were required for sheep brains (fig. 14) as compared with 3% and 33 hours for roast beef (figs. 3 and 4 in preceding paper on beef). An individual who showed an evacuation time of 25 hours for sheep brains (fig. 15) required 3 hours for raw hamburg steak. SUMMARY AND CONCLUSIONS The response of the normal human stomach to roast lamb, stewed lamb, lamb chops and sheep brains was studied using the fractional method of gastric analysis. The results have been tabulated as aver- ages (table 1). Comparisons of lamb cooked in different ways as well as comparisons of lamb with pork and beef have been charted. Lamb was found to require from 2 to 3 hours (average 23 hours) for individuals possessing the rapid-emptying type of stomach to digest -and from 3 to 4 hours (average 3 hours 20 minutes) for individuals with the slow-emptying type of stomach. Roast lamb and lamb chops re- quired practically the same period of gastric digestion and stewed lamb a little longer than the other two. Sheep brains left the stomach rather rapidly (23 hours) and developed a lower acidity than the other meats. Lamb stimulated acid production fully as much as any other class of meats and apparently to a slightly greater extent than beef or pork. The average total acidity at the height of digestion was 134. On the average, roast lamb remained in the stomach a few minutes longer than roast beef but not as long as roast pork. The authors wish to extend their thanks to Dr. R. A. Lichtenthaeler who assisted them in carrying out these tests, and also to those Jefferson men who sacrificed time and convenience in acting as subjects. BIBLIOGRAPHY (1) Fisupack, Smirx, Bercrrm, LicHTENTHAELER, REHFUSS AND Hawk: This Journal, 1919, xlix, 174. (2) Smitu, Fisapack, BerGEIM, ReHruss AND Hawk: This Journal, 1919, xlix, 204. (3) Beaumont: Physiology of digestion, 2nd Ed., 1847, Burlington, Vt. (4) Jessen: Zeitschr. f. Biol., 1883, xix, 129. THE ELECTRICAL CONDUCTIVITY METHOD OF DETER. MINING THE RELATIVE VOLUME OF CORPUSCLES AND PLASMA (OR SERUM) IN BLOOD G. N. STEWART From the H. K. Cushing Laboratory of Experimental Medicine, Western Reserve University Received for publication April 28, 1919 Many years ago (1) I worked out a method of determining the per- centage volume of plasma (or serum) in blood, based upon the fact that the corpuscles may be assumed to be non-conducting particles sus- pended in the plasma. Although the method unquestionably gives more accurate results than the haematocrite and requires little time, it has not been greatly em- ployed even in the laboratory, still less in the hospital. P. Fraenkel (2) recommended it for scientific purposes, after comparing it with Bleib- tren’s chemical method, and Wilson (3) compared it with the haemato- crite method. However, he did not keep up the rotation of the haemato- crite until the column of corpuscles had assumed a constant volume, but rotated for a fixed time (five minutes). This was done purposely because frequently the haematocrite is employed in this way. But although useful comparative results may be obtained on the same blood with a fixed time of rotation, this is not the case where bloods differing greatly in the percentage of corpuscles are to be compared. As the measurement of the conductivity of physiological liquids is a much more familiar operation among biologists and clinicians than it was twenty years ago, and as we have been recently making use of the method again in calculating epinephrin concentrations in serum from the concentrations in the corresponding blood, and have had the oppor- tunity to compare it rather extensively with the haematocrite method, I am confirmed in the belief that its advantages have not been sufficiently appreciated. To be sure, a larger quantity of blood is needed than that required to fill a haematocrite tube. I use a conductivity tube holding about 3 ce. and, therefore, must have 3 cc. of serum. But it is not difficult, as Wilson did, to employ a tube which requires only 4 to 5 233 THE AMERICAN JOURNAL OF PHYSIOLO3Y, VOL. 49, No. 2 4 234 G. N. STEWART drops of ‘blood. The principle of the method permits the assumption that the formulae worked out on dog’s blood will also be applicable to other bloods, since the corpuscles can always be taken as practically non-conducting. In the previous paper the percentage volumes of serum as determined by the electrical method in thirty dogs taken at random are given. The range is from 39.6 to 74.0, and the average 55 per cent. The average for blood specimens taken from six of the dogs used in the recent work is 52 per cent of serum, the range 36.5 to 66.5. The results are compared with haematocrite readings in table 1. TABLE 1 PERCENTAGE OF SERUM BY NUMBER OF i ANIMAL |Electrical ethod Haematocrite 1 52.3 | 48 (5 minutes), 49 (10 minutes), 50 (15 minutes) 2 36.5 | 29.5 (40 minutes), 33 (60 minutes), 35 (70 minutes) 263 66.5 | 62 (15 minutes), 65 (23 minutes) {| 25.5 (10 minutes), 36 (20 minutes), 41 (80 minutes), 45 (40 min- 297 51.0 : : utes) 48 (50 minutes) 306 46.6 | 10 (10 minutes), 25 (20 minutes), 33 (32} minutes) 307 62.0 It will be observed that while great differences exist between the haematocrite readings with a given blood, according to the time of rotation, in no case does the percentage of serum with the longest time of rotation quite equal the percentage determined by the electrical method. The latter obviously constitutes a limit toward which the haematocrite readings approach more nearly the longer the rotation is continued. With some bloods the approach is extraordinarily slow (dogs 2 and 306,e.g.). Where the serum is scanty thisis usually the ease. In dog 306 after 324 minutes rotation the end point had not been nearly reached. The percentage of serum as determined by the haematocrite at this time would have been less than two-thirds of the real percentage. The speed of the haematocrite was about 4000 turns a minute. A very high speed was purposely avoided so as to permit such differences to be readily detected. But with higher speeds they would still exist, although the end point would be reached sooner. In table 2 is given a similar comparison on bloods from eighteen cats. i , ELECTRICAL CONDUCTIVITY TO DETERMINE BLOOD VOLUME 235 TABLE 2 aE PERCENTAGE OF SERUM BY 0) LenS E pees! Haematocrite 1 73 (5 minutes), 73.5 (10 minutes), 74 (15 minutes), 74.5* (20 minutes) 2 62.5 | 57 (8 minutes), 60.5 (16 minutes), 62 (21 minutes) 8 71 (5 minutes), 71.5 (10 minutes), 72* (15 minutes) 9 51.5 (5 minutes), 53.5 (10 minutes), 54.5 (15 minutes), 55* (20 minutes) 91 87*t 214 71.0 239 70.0 259 76.5 | 65 (8 minutes), 70 (15 minutes), 73.5 (20 minutes) 284 50.5 (15 minutes), 51 (22 minutes), 52 (34 minutes) 285 56.5 | 46 (15 minutes), 49.5 (22 minutes,) 52 (34 minutes) 286 67.3 | 32 (5 minutes), 57 (15 minutes), 60 (22 minutes), 62 (30 minutes) 287 44.7 | 30 (5 minutes), 40 (15 minutes), 41 (22 minutes), 42 (80 minutes) 288 | 67.1 289 72.3 | 69 (15 minutes), 70 (25 minutes) 290 | 57.0 | 53 (10 minutes), 56 (20 minutes) 298 82.0 : 305 53.8 | 43 (10 minutes), 48.5 (20 minutes), 51.5 (824 minutes) 308 65 (10 minutes), 68 (15 minutes), 69.5 (20 minutes) 70* (25 minutes) * With these bloods rotation was continued until the increment of the column of serum in successive rotation periods became negligibly small. It was seldom that an absolutely constant length was reached. t This blood as it sedimented in the test tubes obviously consisted mainly of serum. The average for the eighteen cats, including those where only haema- tocrite determinations were made, is 66.2 per cent of serum, the range 44.7 to 87 per cent. The average for all the cats used by us would cer- tainly be distinctly higher, for a number of old animals with an abnor- mally low serum content for a cat are included in the table. In accordance with the fact that the cat’s corpuscles in general sedi- ment much more rapidly on standing than the dog’s, and also because of the lower proportion of corpuscles, the haematocrite readings approxi- mate sooner to the percentage determined electrically. The latter still, however, constitutes a limit which is not exceeded by the haemato- crite determinations. I have found the same to be true for human blood, for example, in a case of diabetes insipidus with anaemia, studied along with Christie (4). Wilson (3) invariably obtained lower serum 236 G. N. STEWART percentages by the haematocrite than by the electrical method in pathological cases. Probably the difference in these cases would have been reduced by longer centrifugalization. That the electrical method gives results which are approximately correct was established by com- parison with two other methods in the former paper (1). It is strong corroborative evidence that the haematocrite readings come nearer and nearer to the values determined by the electrical method, the longer the rotation, without quite attaining them, since some serum is inevitably left in the sediment. In the electrical method no alteration whatever can be produced in the corpuscles, the measurement being made while they are normally suspended in the serum. Since the viscosity of blood is influenced greatly by its content of corpuscles, it is easy to see that very considerable differences may exist in the coefficient of viscosity of the blood of healthy individuals of the same species and in the average viscosity of the blood of different kinds of animals. Burton-Opitz has shown this in his elaborate investigations on the viscosity of blood. He found that the viscosity of dog’s blood was on the average five times greater than that of distilled water (at 37°C.), that of rabbit’s blood only 3.4 times greater, while cat’s blood possessed an intermediate value. Lewy (6) also observed a great difference in the viscosity of blood from different animals of the same species as well as in animals of dif- ferent species. Welsh (7) found a considerable range in healthy human beings and of course very great variations in disease. The fact that great variations in the viscosity are compatible with a perfectly efficient circulation, suggests that the emphasis which has been placed on the superiority of such substances as gum or gelatine as constituents of transfusion liquids is scarcely warranted. In so far as they may attract water from the tissues and retain it in the circulation, they may have some advantage. But when it is argued that since gum or gelatine solutions by increasing or maintaining the viscosity of the blood enable a greater arterial pressure to be attained, they must be superior to simple salt solutions, the physiological basis for the conclu- sion seems open to question. Why should it be necessarily advantageous fe artificially increase the resistance which the heart must overcome in order to drive blood through the tissues? When the viscosity is increased the resultant rise of blood pressure, provided the response of the heart is adequate, does not mean as a matter of course that the tissues are getting more blood than before but may merely mean that the heart by working harder ELECTRICAL CONDUCTIVITY TO DETERMINE BLOOD VOLUME 230 is able to deliver to them as much blood as before. It is true that the physiologist or the physician who is estimating the blood pressure may have the satisfaction of seeing it mount toward what is considered a normal level, but beyond this it is not clear that there would be any necessary advantage. If the response of the heart is inadequate and the rise of blood pressure is insufficient to overcome the extra resistance, the blood flow in the tissues may be diminished although the pressure has been increased. Of course, it may be argued that a certain minimum blood pressure is essential and that if this were not reached the organs, including the heart, would not function properly, even if a sufficient blood flow through them could be maintained. This, however, is one of the moot points of physiology, while there is general agreement that the important thing is a sufficient flow of blood. There are certainly conditions in which this essential blood flow might be promoted by diminishing the viscosity of the blood. If no other change occurred the blood pressure might be expected to fall. But where: the blood viscosity is diminished by the injection of salt solutions the volume of the circulating liquid is at the same time increased, and if the pressure does not fall (it is not necessary that it should rise) the blood flow will be increased. When blood corpuscles are injected the viscosity is necessarily increased and the flow to that extent rendered more difficult. But there is the compensating advantage, which is most obvious in haemorrhage, that the increased viscosity is due to the addition of essential elements to the blood, an advantage which, of course, does not exist in the case of gum. These remarks are not intended in any way to prejudge the question whether clinical experience or physio- logical experiments may not have demonstrated the superiority of solutions containing such substances as gum. BIBLIOGRAPHY (1) Stewart: Journ. Physiol., 1899, xxiv, 357. (2) FRAENKEL: Zeitschr. f. klin. Med., 1904, lii, 476. (3) Witson: This Journal, 1905, xiii, 139. (4) CHRISTIE AND Stewart: Arch. Int. Med., 1917, xx, 10. (5) Burron-Opitz: Journ. Amer. Med. Assoc., 1911, lvii, 353; Pfliiger’s Arch., 1900, Ixxxii, 447; Journ. Physiol., 1905, xxxii, 8. (6) Lewy: Pfliiger’s Arch., 1897, Ixv, 447. (7) Wetsu: Heart, 1911, iii, 118. THE EFFECT OF FEEDING PARS TUBERALIS AND PARS ANTERIOR PROPRIOR OF BOVINE PITUITARY GLANDS UPON THE EARLY DEVELOPMENT OF THE WHITE RAT CARLETON J. MARINUS From the Research Laboratories of Parke, Davis and Company Received for publication May 1, 1919 INTRODUCTION The pituitary body (hypophysis) is usually described as made up of two component parts, the anterior and posterior lobes (1). Under the general term posterior lobe are included the pars nervosa, the pars intermedia and the neural stalk. Functionally these structures are very closely related. Extracts of each of them are capable of producing similar characteristic immediate effects when injected into the blood stream. It is believed that the active principles of the posterior lobe are elaborated in the pars intermedia and traverse the pars nervosa and neural stalk to the third ventricle, thus reaching the cerebrospinal fluid (2). The pars intermedia is histologically distinct from the pars ner- vosa and neural stalk, and traces its embryological origin to an entirely separate anlage. It is, however, very closely joined to the pars nervosa and is an essential part of the posterior lobe. Injection of extracts prepared from the anterior lobe produce none of the effects characteristic of posterior lobe extracts. LLong-continued feeding with the anterior lobe tissue, however, induces certain altera- tions in development, while the use in a similar way of posterior lobe preparations gives negative results. Robertson in 1916 published a report in which he states that when fed to growing mice, anterior lobe produced a definite retardation of growth in the period immediately following puberty, this retardation being succeeded by a marked stimulation of growth (5). Goetsch, working with a much smaller number of white rats, stated that anterior lobe induced a uniform increase of growth-rate, denying the period of retar- dation (6). Later, Robertson and Delprat reported that anterior lobe feedings definitely increased the prepubertal growth rate of white mice. 238 EFFECT OF PITUITARY FEEDING ON GROWTH 239 The anterior lobe is also known to exert a certain control over the development and proper functioning of the reproductive system. Clinically, pituitary disease is always associated with more or less sexual abnormality, both anatomical and functional (9). Partial extirpation of the anterior lobe in experimental animals is followed by marked hypoplasia of the genitalia (3). Goetsch noted a marked hypertrophy of the genitalia in his pituitary-fed animals (6), while Robertson noted an increase in pugnacity and general virility in his pituitary-fed males (5). Recently it has been shown that in addition to the structures men- tioned above, the hypophysis contains a third epithelial lobe, the pars tuberalis, closely investing the neural stalk (10). The question arises whether this newly described structure is a part of the posterior or of the anterior lobe, or whether it possesses an entirely separate function. From its structural relations it might at first be considered a part of the posterior lobe complex for it is apparently continuous with the pars intermedia which has been proven to be a part of the posterior lobe mechanism. Atwell (11) has shown, however, that, in the rabbit at least, the pars tuberalis is embryologically quite distinct from the pos- terior lobe elements, arising as two lateral thickenings of the anterior lobe anlage and only later surrounding the developing neural stalk. In a recent paper Atwell and Marinus (12) have compared the blood. pressure and oxytocic reactions of pars tuberalis extracts with the re- actions of pars intermedia, neural stalk and pars nervosa extracts. The reactions elicited by pars tuberalis extracts were so small that they were evidently due to unavoidable contamination of the extracts with active posterior lobe constituents, and not to any inherent activity on the part of pars tuberalis. It was concluded by the authors that the pars tu- beralis is not a functional part of the posterior lobe. Owing to its close anatomical relationship to the anterior lobe it was suspected that the pars tuberalis might be included in the ordinary anterior lobe preparations. Investigations showed that such was the case. As the anterior lobe is rolled from its capsule a small bit of the pars tuberalis is usually left attached to the pars anterior proprior. This fact opens the possibility that some of the effects of the anterior lobe feeding may be due to the inclusion of small portions of the pars tuberalis in the preparation. In the present study, white rats have been fed upon carefully separated pars tuberalis and pars anterior proprior, in an attempt to answer this question. 240 CARLETON J. MARINUS MATERIAL AND METHODS In this experiment albino rats were fed portions of the pituitary gland, and carefully observed for any changes in growth rate and sexual devel- opment. The rats used were secured at the age of two to three weeks (shortly after weaning). They were immediately weighed and grouped according to weight and sex. Three separate series of experiments were TABLE 1 Experiment 1. Gain in body weight (in grams) AFTER 6} WEEKS OF | AFTER 12 WEEKS OF FEEDING FEEDING Sx Bileae |e edhe lie aSelans| ag |ase| anal at B22|Sa5| S5 | 325 S28) Ss 1) 9) .o) ©) 16) ie) (| Number in group............. 6 2 4 Very young)| Average final weight......... 72.6 |68.0 |73.1 | Not weighed ~ females Average initial weight........ 16.0 |16.7 |17.0 because of Average gaini\;.2:.cuienia aie 56.6 |51.3 |56.1 pregnancies Number in group.............| 4 3 3 }| Average final weight......... 98.2 /83.1 |97.8 | Not weighed pone eerailes Average initial weight........ 36.4 |35.3 [38.8 because of Average gain.................|61.8 |47.8 |59.0 pregnancies Number in group sss sec cle + 2 4 2 Very young Average final weight......... 74.7 |84.2 90.5 |97.0 males Average initial weight........ 18.2 {16.7 18.2 |16.7 IAVErAge Paine sae eee ee 56.5 |67.6 72.7 180.3 () Number in group............. 3 3 3 3 3 3 nae ears Average final weight......... 113.6/107.1)113.5)130.3/121.3)134.3 , Average initial weight........ 38.3) 38.6) 46.0) 38.3) 38.6} 46.0 INOUE AS (ANd bo beeen ooo nee Be 75.3) 68.5| 67.5| 92.0) 82.7) 88.3 conducted, one group comprising fifty-three rats, the second, thirty- seven, and the third, ten. The third series contained a single litter born at this laboratory. During the entire experiment the rats were kept on a standard diet consisting of water and cracked mixed grains in abundance, stale (but not mouldy bread) once a week, and a small quantity of fresh milk daily. The rats were kept in metal cages, without litter except for the EFFECT OF PITUITARY FEEDING ON GROWTH 241 grain they scattered about. The cages were cleaned weekly, using a coal-tar disinfectant. Individual rats were distinguished by spotting with stains—methylene blue, acid fuchsin and picric acid proving the most satisfactory. Each rat was weighed twice weekly. In addition to the standard diet the rats were daily given the experi- mental foods. A small portion of the fresh gland was presented to the rat in forceps, whereupon it was invariably seized and swallowed. At TABLE 2 Experiment 2. Gain in body weight (in grams) AFTER 5} WEEKS OF | AFTER 11 WEEKS OF FEEDING FEEDING mica 8 Hs, Ei a) “> = aS¢| ana! os | as eae a3 sa) ga8| 8 | 228) sa3| 35 1) oO oo) ©) ie) o Number in group........... 3 3 4 Very young fe-|}| Average final weight....... 61.3] 61.3] 63.2) Not weighed males Average initial weight...... 22.5] 27.5] 26.11 because of Average gain ..............| 88.8] 33.8] 37.1] | pregnancies Number in‘ group). 2.2 6.0.0: 5 4 6 Giger etamales Average final weight....... 94.9) 91.2} 94.3) Not weighed Average initial weight...... 44.8) 47.1) 45.5} because of Average gain...............| 50.1] 44.1] 48.8] ~ pregnancies Number ingroup: .2625../.3./ 7 5 5 7 5 5 Very young}| Average final weight....... 76.4} 62.9} 73.9)116.4) 94.0)109.0 males Average initial weight...... 29.5} 30.1) 30.0} 29.5) 30.1] 30.0 Average gain .............. 46.9) 32.8) 43.9] 86.9) 64.1] 79.0 Number in group........... + 4 3 4 4 3 ile males Average final weight... ....|109.4/ 90.0/101.8)148.5}119.5)138.5 Average initial weight...... 46.9} 44.0) 45.3) 46.9] 44.0) 45.3 PV CTA PO AIT. 5 0:0 010.000 ofe0.4 ous 62.5} 46.0} 56.5]101.6] 75.5} 93.2 each feeding it was definitely ascertained that the portion allotted was completely devoured. The glands used were taken indiscriminately from steer, cow and heifer heads. As soon as possible after the animal was slaughtered the head was split in the sagittal plane and the pituitary gland dissected out. The glands were immediately wrapped in oiled paper and packed in ice. In every case the glands were dissected into their component parts and fed to the rats within six hours after the TABLE 3 Experiment 8. Gain in body weight (in grams). After 63 weeks of feeding GROUP I. ANTERIOR GROUP II. PARS LOBE TUBERALIS GROUP III. MEAT hla tate CRC op am er cape) 1. Female.........0:.......| 82.01105.5) 73.5]. 32.0} 80.5] 4875] 3295|/9620\"G315 2. Female...................] 35.0/118.5| 83.5] 34.0) 88.5} 54.5] 33.0) 94.0} 61.0 3. Male. .2..:.......2.2-..2.| 36.5]129.5! 93.0] 32.0/100.0) 78:0) 37_O12°5\i7aes Al SMIDNOS cee ore oo ee os eee 33.5} 87.5] 74.0 Total... 2.22.0. 02.0...2. +. 1108.5/853-5|250- 0/131. 51350. 5|255.0/102 51302520008 AVELASC: ch. Uae 34.5)117.8) 83.3) 32.9] 89.1] 63.7) 34.1/100.8| 66.6 Relative alien meme ete none site toh LOO 95.0 100.0 Normal valuedeatalOOl aw marets es cee (cf.table 5) TABLE 4 Experiment 3. Body lengths in centimeters after 63 weeks of feeding GROUP IV. Keaenras wea uur s te de Memale:: 0... sav actions Cec be ee 15.2 13.6 Divemale : 2): i. icobth te eb ectenee eke eae 16.2 13.9 Sr Malen si58.... Jc Sink. ee sooo cua ae 16.3 15.2 AVE Bled test: 5 AS ech aitobe ok OG 2:2 52 och Bice dees See 47.7 42.7 BAVCLALE: joc. ihe tee ae OM cree ae eas 15.9 14.2 TABLE 5 Experiment 3. Weights of genital organs in milligrams epQunLE| aero} enone 25 | eco ete Male Female | Male Female | Male Female 1 160 120 115 2 220 100 140 3 1530 885 910 4 865 Averdgelun hind. Lae ee 1530 190 875 110 910 135 Relative: variation 4. :.... 0506.6 168 96 100 Normal valued at 100............ 140 81 100 EFFECT OF PITUITARY FEEDING ON GROWTH 243 death of the animal. During this time there was no actual contact be- tween the ice or ice water and the glands. These precautions were taken in order to make certain that the material should lose none of its activity by autolysis, by decomposition or by solution of its constitu- ents in the ice water. The partes tuberales were dissected out as described by Atwell and Marinus. The material available was then divided into equal portions sufficient to supply all the rats to be fed. Each rat was given a quan- tity of pars tuberalis which varied from day to day but which approxi- mated one-fourth of an entire pars tuberalis. TABLE 6 Experiment 2. Birth of first litter and weight of mother at conception sano ee GROUP III. MEAT Bras 3 = 3 E qibeweek of feeding..« .isc..%e<605.04,,,4,.,LOL.0 SHIT WEC KNEE oe ot avcs5,4-.5° tojs'. a croierasens Sites 2 | 94.0 90.0 GUneweekipierie ties eset eee Mi CW ECL e ae oo ee eee Se 1 |107.5 Vt Ce etay Pees cecnd Ne totscecdietonsin dec DPN AS Eas 12055 1 107.0 WTS Keser cycet ciepcleiers sieusue lc ele ove ors 1 122.0 2 94.0 89.5 HeSpamWcelcna eee, cd oui SRE, Cb ids 2 94.5 2 127.0 (2 preg.) | 85.5] (8 preg.) |121.5 PNVET AGC CW ELON G trocar crolet ciara raisiiansiaisc site isis 100.9 100.6 107.8 The anterior lobes were secured by splitting the glands in the mid- sagittal plane and rolling the entire anterior lobe out of its capsule, leaving the posterior lobe attached to the capsule and dura mater. The portion of the anterior lobe at the point of origin of the pars tuberalis was snipped off, making certain that no pars tuberalis fluids or tissues were included with the anterior lobe as fed. Each rat was given a por- tion equal to about one-sixth of the entire lobe (approximately 250 mgm.). Asa control certain of the rats were fed beef muscle. A por- tion of the muscle was freed from all loose fat and was then divided into: portions approximately equal in weight to the portions of anterior lobe. 244. CARLETON J. MARINUS All the rats in series 3 (see above) were killed with ether after six and one-half weeks of feeding. The body weights and lengths were recorded. The entire female genital tract was dissected out down to the trigone and preserved intact. The sex organs were then fixed in Bouin’s fluid and dehydrated in alcohols. When in 80 per cent alcohol each testis (together with the corresponding epididymis) was weighed separately. The female genital tract was weighed as a whole. The tissues were completely dehydrated, cleared with xylol, imbedded in paraffin and cut 5 micra thick. The sections were stained with Heidenhain’s iron haematoxylin and eosin. DISCUSSION Puberty occurs in the white rat from sixty to ninety days after birth (13). The rats of experiments 1 and 2 were then barely approaching the normal time of puberty after six and one-half and five and one-half weeks of feeding. This stage corresponds roughly to the end of the second or beginning of the third growth cycle described by Robertson for white mice. Comparison of the weights at this stage (tables 1 and 2) shows a small but well defined increase in weight in the anterior-lobe- fed groups over all other groups. This is in agreement with Robertson and Delprat who conclude that anterior lobe feeding stimulates growth during the second development cycle. The rats of experiment 3 were born in the same litter and allow more exact comparisons. Here also the anterior-lobe-fed surpassed the other animals at the age of nine weeks (after six and one-half weeks of feed- ing) (table 3). The difference is even more marked in this experiment owing to the greater uniformity of the animals. After twelve weeks of feeding all the females had given birth to at least one litter or were in some stage of pregnancy. The rats had, there- fore, all passed puberty. At this stage, also, the anterior-lobe-fed males were heavier than any of the others, the difference being greater than at the age of puberty. This observation is contrary to Robertson’s conclu- sions that after puberty the administration of anterior lobe to white mice produces a preliminary retardation of growth. The seeming incon- sistency may be due to a possible difference in the relative lengths of the growth cycles of white mice and white rats. The nose-to-anus lengths recorded in table 4 show that the anterior- lobe-fed rats were considerably larger than cither the controls or the ‘pars-tuberalis-fed rats. The increased weights noted in the case of the EFFECT OF PITUITARY FEEDING ON GROWTH 245 anterior-lobe-fed rats are, then, due to an increased skeletal growth. This conclusion is in keeping with the increased skeletal growth noted in cases of pathologic hyperpituitarism. While the anterior-lobe-fed rats were growing faster than the controls, the pars-tuberalis-fed animals were losing ground. In all three experi- ments the pars-tuberalis-fed rats were markedly smaller than the con- trols. This was even more constant and more marked than the over- growth of the anterior-lobe-fed animals. It should be remarked, however, that the pars-tuberalis-fed rats were not strictly controlled. The rats of the other groups received daily a quantity of muscle or glandular tissue weighing approximately 250 mgm. while the tuberalis- fed rats were given only a minute portion of tissue weighing but 5 to 10 mgm. It is evident that the accelerated growth reported by previous obser- vers as following anterior-lobe-feeding has not been due to any admix- ture of pars tuberalis substance, inasmuch as the same effects are pro- duced by anterior lobe material known to be free from other parts of the gland, and inasmuch as no overgrowth is induced by feeding pars tuberalis alone. The apparent retardation of growth must be further studied before it is to be definitely ascribed to pars tuberalis feeding. In addition to its action on the process of growth, the anterior lobe is known to control, to some extent at least, the development of the repro- ductive system. The effects of anterior lobe feedings on the sexual organs may be evaluated by a, study of the organs themselves, or }, date of birth of the first litter. Both methods have been used in this study. The testes of the anterior-lobe-fed male (experiment 3) were markedly larger than those of the other males, weighing nearly twice as much as the controls. Upon section it was found, as reported by Goetsch, that all of the tissues in the testicle are involved in the hyperplasia but that the increase in size and weight is chiefly attributable to changes in the seminiferous tubules. The female organs were also better developed although the gross difference was not so marked. The genital organs of the pars-tuberalis-fed rats could not, however, be distinguished from those of the controls. The slightly greater weight of the control organs is within the limits of individual variation and is explained as concomitant to the larger size of the control animals. Microscopical examination of both testes and ovaries revealed no dif- ference between those of the pars-tuberalis-fed and control rats. 246 CARLETON J. MARINUS In normal healthy rats the first copulation occurs shortly after the sex glands become histologically mature. Thus the date of birth of the first litter is a good criterion of the relative maturity of two groups of animals. During the ninth week of feeding it became evident that several of the anterior-lobe-fed animals were pregnant, while none of the controls were showing signs of pregnancy. This observation was borne out by the fact that three anterior-lobe-fed females gave birth to the first litters two weeks before any of the control litters were born. The females evidencing this sexual precocity were not larger than the slower controls at the calculated date of impregnation, 1.e., the sexual develop- ment had been more rapid than the somatic. The pars-tuberalis-fed and control females dropped their litters during the same period of time, averaging more than two weeks after the anterior-lobe-fed females. In keeping with the microscopical evidence afforded by experiment 3, the births in this experiment. show that the pars-tuberalis-feedings do not alter the sexual development or function of the white rat. SUMMARY AND CONCLUSIONS One hundred young rats were separated into three groups. The first group was fed upon pars anterior proprior of the pituitary gland, the second upon pars tuberalis, and the third or control group upon beef muscle. During twelve weeks of feeding the rats of the first group exhibited increased growth rate accompanied by a more rapid develop- ment of the reproductive system, evidenced by gross and microscopical hypertrophy of the organs and by the earlier birth of young. In the second (pars tuberalis fed) group there was no change in the sexual development as compared with that of the control group. The growth rate was slightly slower in the second group, ow ving perhaps to the smaller amount of meat fed. This study has not shown that any of the functions ascribed to the anterior lobe as a whole are due to the pars tuberalis. I wish to express my indebtedness to Dr. Wayne J. Atwell for his valuable assistance in the preparation of this paper. = EFFECT OF PITUITARY FEEDING ON GROWTH 247 BIBLIOGRAPHY (1) Brnpu: Innere Sekretion, 19138, 2 Aufl., Heft. ii. (2) Herrine: Quart. Journ. Exper. Physiol., 1908, i, 121. (3) Crown, CusHina AND Homans: Bull. Johns Hopkins Hosp., 1910, xxi, 127. (4) Aupricw: This Journal, 1912, xxx, 352. Wouzen: This Journal, 1914, xxxiv, 127. ScHAFER: Quart. Journ. Exper. Physiol., 1912, v, 203. Lewis AnD Mitumr: Arch. Int. Med., 1913, xii, 137. (5) Roprertson: Journ. Biol. Chem., 1916, xxiv, 385. (6) Gortscu: Bull. Johns Hopkins Hosp., 1916, xxvii, 29. (7) RoBERTSON AND DevpratT: Journ. Biol. Chem., 1917, xxxi, 567. (8) Barney, E. L.: Journ. Lab. and Clin. Med., 1918, iii, 480. RoBERTSON AND Burnett: Journ. Exper. Med., 1916, xxiii, 631. (9) Faura anp Meyers: The ductless glandular diseases, 2nd ed., 1916. (10) Tinney: Internat. Monatschr. Anat. and Physiol., 1913, xxx, 258. (11) Atwexu: Amer. Journ. Anat., 1918, xxiv, no 3. (12) AtwreLut aNnD Marinus: This Journal, 1918, xlvil, 76. (18) Donatpson: The rat, Memoirs of Wistar Inst., no. 6. THE RELATION OF HYPOPHYSIS TO GLYCOGENOLYSIS ROBERT W. KEETON anp FRANK C. BECHT From the Laboratories of Pharmacology, University of Illinois College of Medicine, and Northwestern University Medical School, Chicago Received for publication May 8, 1919 In a previous report it was shown by the authors (1) that stimulation of the hypophysis produced a hyperglycemia, which did not occur if the stimulus was applied contiguous to but not on the gland, and that this rise in sugar was absent in animals whose splanchnic nerves had been previously sectioned. The present study was undertaken to determine the significance of this apparent nervous relation of the hypophysis to the glycogenolytic process. The same general plan of experimentation previously adopted was followed. The blood sugar however was estimated by the Benedict method as modified by Meyers and Bailey (2) and by Benedict (8) rather than by the Bertrand (4) titration after the removal of proteins in acid sodium sulphate solutions. Stimulation of gland. It was soon observed that under etherization alone the colorimetric methods gave a continuous persistent rise in glycemia despite the use of precautions to rule out all influences other than ether. A study of this mechanism was undertaken and has been recently reported by one of us (5). Stimulation of the hypophysis gave in some of the animals a glycemic level which was no higher than that attained by ether stimulation alone. In other cases the level was distinctly above that ever obtained by simple etherization. Responsiveness of different animals to such experimental procedure shows rather wide individual variations, so that it is difficult to establish a normal. Consequently a quantitative value cannot always be assigned to the ether hyperglycemia. However, the character of the curves under the two experimental conditions differ. Ether shows a slow rise with a maximum attained in the interval between second and third hour. With constant ether administration the curve appears within these ranges to be a simple function of the time. Following the excitation of the hypophysis, whether it be done mechanically (as in 248 4 oa RELATION OF HYPOPHYSIS TO GLYCOGENOLYSIS 249. drilling the bone out over the gland or manipulating it in its removal); or electrically, there is an immediate step up in the blood sugar. ‘The quantity of sugar so liberated may be greater than would appear under prolonged etherization but of this we have no conclusive proof. How- ever, the evidence furnished on stimulating the gland in animals with denervated livers is strongly suggestive that an increase above the ether level occurs. Certainly it is clear that there is an immediate accelera- tion of the glycogenolytic process. - TABLE 1 Stimulation of hypophysis in normal animals AFTER ANIMAL BEFORE ETHER Time of Ether Drilling? | Stimulation Rest experiment in minutes “il 0.094 0.091 0.088 0.100 0.106 73 2 0.088 0.113 0.182 0.232 0.183 75 3 0.124 0.176 0.193 0.169 55 4 0.115 0.136 0.260 0.273 63 5 0.145 0.201 0.243 105 6 0.096 0.133 0.146 0.155 0.160 80 * Attempt had been made to section cord in this animal previously. Appetite good but he never regained complete health. + Gland exposed by using a dental drill. The results are the average of duplicate estimations, figured to the percentage of dextrose in the whole blood. Doubly splanchnectomized animals. In the previous report it was shown that when the splanchnic nerves were cut the rise in sugar did not follow the hypophyseal senemeees This finding was confirmed in two animals: Dog 25. Splanchnics were sectioned 17 days previously; the blood sugar after relaxation under surgical anesthesia 0.128 per cent; 1 hour and 43 minutes later during which gland was exposed and stimulated, 0.093. Dog 26. Splanchnics cut 7 days previously; after surgical anesthesia, 0.087; 45 minutes later during which the gland was exposed and stimulated, 0.091. Section of nerve in hepatic pedicle. In the first two cases (animals 7 and 8) only the nerves about the hepatic artery were cut. In the others (9, 10, 11) all of the structures in the hepatic pedicle were severed. The coats of the artery vein and common bile duct were cauterized lightly with hot iron. This precaution, as had been shown by Macleod (6), THE AMERICAN JOURNAL OF PHYSIOLOGY, VOL. 49, NO. 2 250 ROBERT W. KEETON AND FRANK C. BECHT must be taken if one is to be certain of a complete separation of liver from its nervous connections. Animals so operated have been shown previously (5) to give a lower hyperglycemic response to ether than normal animals. The last column of table 2 shows these ether control values reproduced from the former study. Table 2 indicates quite clearly that the blood of these animals attains a high grade of hyperglycemia following excitation of the hy- pophysis. This rise in comparison with the control experiments suggests further that stimulation of the gland probably not only initiates and accelerates the glycogenolysis, but also raises it to higher level than ether alone does under similar experimental conditions. TABLE 2 Effect of stimulation of the hypophysis after section of nerves in the hepatic pedicle AFTER ANIMAL BEFORE ETHER Control after Ether Drilling Stimulation Rest 3 hours ether anesthesia Hepatic artery denervated* v4 0.101 0.137 0.208 0.216 0.234 8 Osi 0.201 0.225 0.234 Section of all nerves in pediclet 9 0.105 0.148 0.167 0.248 0.277 0.132 10 0.083 0.106 0.161 0.168 0.163 0.124 11 0.090 0.095 0.133 0.164 0.117 * Nerves removed from artery alone and coats cauterized. + Entire pedicle sectioned except hepatic artery, portal vein and common bile duct. Coats of these were cauterized. Transection of cord. The cord was transected by removing the second dorsal spine and severing it with a sharp-pointed probe. It was sug- gested in our former study that the alleged hormone, which Weed, Cushing and Jacobsen (7) believed they had liberated in the stimulation of the hypophysis and the superior cervical ganglion, might really exist and might find its site of action on the terminations of the pre-ganglionic splanchnic fibers which we had destroyed in our splanchnectomy. In order to test out this hypothesis, the experiments on animals with transected cords were performed. Reference to table 3 shows that such animals were used in all stages of recovery (from four to thirty-six RELATION OF HYPOPHYSIS TO GLYCOGENOLYSIS 251 days), so as to eliminate the vasomotor instability associated with spinal shock and that in none of these was there a suggestion of hyper- glycemia. TABLE 3 Stimulation of hypophysis in animal with cord transected ut the level of second thoracic vertebra AFTER DAYS AFTER ' ANIMAL TRANSECTION | BEFORE ETHER Ether Drilling Stimulation Rest 12 4 0.108 0.111 0.117 0.076 0.088 13* 6 0.112 0.060 0.076 0.082 14 16 0.077 0.093 0.077 0.071 0.063 15 21 0.102 0.091 0.098 0.089 0.073 16* 25 0.069 0.087 0.084 0.112 0.111 17 36 0.104 0.097 0.088 0.071 * Sugar estimated by sodium sulphate precipitation: Bertrand titration; others by colorimetric method. TABLE 4 Glycemia following hypophysectomy | AFTER REMOVAL OF GLAND AFTER DRILLING] Jme- diately AFTER ANIMAL ETHER Hours expressed as exponents Normal animal 18 0.143 | 0.227 | 0.277 | 0.093%; 0.055°; 0.08374; 0.06247; 0.067109 19 0.143 | 0.142 | 0.137 | 0.0933; 0.099°; 0.0727; 0.062*6 20 | 0.143 | 0.273 | 0.311 | 0.10018; 0.09275 21 0.153 | 0.146 | 0.153 | 0.1074; 0.09277; 0.08346; 0.10372; 0.1034 Complete denervation of hepatic pedicle 22 0.143 | 0.168 | 0.330 | 0.134°; 0.0908 23 0.106 | 0.161 | 0.156 | 0.1364; 0.09077 24 0.090 | 0.134 | 0.167 | 0.0854; 0.0695; 0.08979 Splanchnic nerves on both sides sectioned 2. or | 0.128 | 0.124 | 0.102 | 0.095°; 0.09474 Hypophysectomy. Cushing and associates (8) have reported that in dogs a transitory glycosuria follows hypophysectomy, manipulation of gland or compression of stalk with a metal clip. The literature has been 252 ROBERT W. KEETON AND FRANK C. BECHT critically reviewed by Goetsch (9) but these workers are apparently the only ones who have investigated the relation of hypophysis to carbo- hydrate metabolism using the methods of glandular removal and elec- trical stimulation. We desired to know the duration and persistence of this hyperglycemia, so glands were removed in several animals as shown in table 4. Examination of the data shows that within three to five hours after the removal, the sugar level is normal and remains so until death. In animal 19 there appeared to be some evidence of hypoglycemia but this we attributed to his moribund condition. No attempt was made to determine the completeness of the removal by microscopic section, since the animals died with all the evidences of insufficiency within the usual time limits. DISCUSSION The data presented demonstrate clearly that if the stimulus be pre- vented from reaching the level of the adrenals no hyperglycemia results from stimulation of the hypophysis. A hormone! if liberated by the stimulation does not act on any of the peripheral mechanism of glyco- genolysis. For section of the cord leaves the splanchnic nerves (both pre- and post-ganglionic fibers), all their terminations in the adrenals and liver intact, and yet, following this, the experiment does not give a hyperglycemia. Such a hormone would have to find its site of action on some central cranial structure. If the pathway be assumed to be a nervous one, then section of splanchnics removes the block a little further peripheralward, a pro- cedure which prevents the hyperglycemia. Section in hepatic pedicle beyond the adrenals does not interfere with the rise in blood sugar. These findings are all analogous to those of Macleod (10) on stimulating splanchnic nerves, and Keeton and Ross (5) in their study of ether hyperglycemia. It appears then that excitation of the hypophysis has originated a stimulus which is directed peripheralward by nervous con- nections and falls upon the splanchnic-adrenal-hepatic mechanism controlling the ultimate partition of glycogen. _ The transitory nature of the hyperglycemia following the removal of the hypophysis coupled with the maintenance of a fairly normal sugar level until death we believe points to the fact that the rédle played by the hypophysis in carbohydrate metabolism deals not with the 1 Under the term “‘hormone”’ is included any chemical product formed in one organ which may stimulate any other organ to activity. RELATION OF HYPOPHYSIS TO GLYCOGENOLYSIS 253 process of glycogenolysis, but with some other phase. Indeed the well established alteration of sugar tolerance in cases of acromegaly and pituitary tumors (11) as well as the studies of Cushing in carbohydrate tolerance after removal of the posterior lobes indicate that future inves- tigation should be directed toward the influence of the hypophysis on the utilization of the sugar by the organism. CONCLUSIONS 1. Stimulation of hypophysis in dogs causes hyperglycemia inde- pendently of the ether used in the anesthesia. 2. This hyperglycemia is absent after transection of cord at level of second thoracic vertebra and after section of the splanchnics. It per- sists after section of the nerves in the hepatic pedicle. 3. Following hypophysectomy a transitory hyperglycemia occurs, and persists three to five hours. After this the sugar level remains normal until death. 4. If a hormone is liberated by stimulation of the gland, it must have a central action. 5. The view is favored that the pathway is a nervous one mediated through the splanchnic nerves to their terminations in the adrenals and liver. 6. The physiological role played by the hypophysis in carbohydrate metabolism does not deal with transformation of glycogen into sugar, but more probably with the utilization of the sugar by the organism. BIBLIOGRAPHY (1) Kerton AND Becut: This Journal, 1915, xxxix, 109. (2) Mryers AnD Battery: Journ. Biol. Chem., 1916, xxiv, 147. (3) Benepict: Journ. Biol. Chem., 1918, xxxiv, 203. (4) Sonntaa: Biochem. Zeitschr., 1913, liii, 501. (5) KEETON AND Ross: This Journal, 1919, xlviii, 146. (6) Macitreop anp Pearce: This Journal, 1912, xxix, 419. (7) WrED, CUSHING AND JACOBSEN: Johns Hopkins Hosp. Bull., 1913, xxiv, 40. (8) Crown, CusHine AND Homans: Johns Hopkins Hosp. Bull., 1910, xxi, 127. (9) GortscH, CusHING AND JAcoBsEN: Johns Hopkins Hosp. Bull., 1911, xxii, 165; 1910, xxi, 260. GortscH: Quart. Journ. Med., 1914, vii, 173. (10) Mactrop: Diabetes, 52. Mactreop AND Pearce: This Journal, 1912, xxix, 419. Macteop: This Journal, 1908, xxii, 373. (11) BorcuarnptT: Zeitschr. f. klin. Med., 1908, Ixvi, 332. THE GASTRIC RESPONSE TO FOODS! VI. DIGESTION IN THE NorMAL HUMAN STOMACH OF Eacs PREPARED IN DIFFERENT WAYS RAYMOND J. MILLER, HARRY L. FOWLER, OLAF BERGEIM, MARTIN E. REHFUSS anp PHILIP B. HAWK From the Laboratory of Physiological Chemistry of Jefferson Medical College, Philadelphia Received for publication May 7, 1919 Eggs like meats are particularly rich in protein. Hence their diges- tion is carred out to a considerable extent in the stomach and is of more than usual interest not only from the standpoint of normal nutrition but also from that of clinical dietetics, inasmuch as eggs in the raw state or prepared in different ways are frequently used to replace meat in the diet of invalids. Beaumont (1) found that raw egg white left the stomach of his subject (Alexis St. Martin) very quickly, in fact sooner than any-other food investigated. Pavlov (2) noted in dogs that such egg white produced no stimulation of gastric secretion. Bateman (3) found the utilization of raw egg white to be poor, particularly when large amounts were fed to dogs, and that this indigestibility was due to the ovalbumin which the egg white contains. Penzoldt (4) studied the evacuation times of eggs in the human stomach, using a large stomach tube, and obtained as ° the result of five experiments the values given in table 1. Jaworski and Gluzenski (5) reported that it required one and a quarter hours for the white of one egg, finely chopped and taken with two and one-half ounces of water, to leave the stomach. Water has, however, in itself a stimulatory effect upon secretion (6). The present study was made to determine the response of the normal human stomach to eggs prepared in different ways. The fractional method of gastric analysis was employed to follow the course of digestion. The experimental conditions and the methods employed were in general those used in the earlier work carried out in this laboratory upon meats 1 The expenses of this investigation were defrayed by a fund furnished by Mrs. M. H. Henderson, the Curtis Publishing Company and Dr. L. M. Halsey. 254 — GASTRIC RESPONSE TO EGGS 255 (7). The subjects were normal medical students who came to the labor- atory at 8:00 a.m. without breakfast. Residuums were not removed. The number of eggs given to each man was two except where otherwise specified. The subjects were permitted to eat these in their ordinary manner. The time required was about ten minutes with not more than two or three minutes variation. Most of the subjects of these tests swallowed the tube without assistance and showed no signs of discomfort. They remained seated most of the time and at rest, i.e., talking, reading and copying notes. Samples were withdrawn at 15 minute intervals and kept in ice water for the short period preceding analysis. Lavage was used in every case to determine conclusively whether the stomach was empty or not. In practically every case the results of lavage were con- firmatory, showing that the stomach can be completely emptied by means of the tube used. In a few cases it was necessary to discontinue the experiment after a period of hours before digestion was complete. TABLE 1 : Evacuation times of eggs from the stomach (Penzoldt) PREPARATION EVACUATION TIME hours 2) celote be Tio! G0] Re Res 6a a aa ee Pa z 2 TEN CUES 3 GB e Bag TUS Eee ao EE ne ne nearer e z memancned lepes: 5 grams! Dubter,. .. occ. 66. ce ce eee ec ee ce os 5 PME OMLE CC PES bocs)s tata 4 artis) asarAuapyels aralldiaveld ae ured ereve'e RRO 3 “RRS TOT) G Ee ne a nnn eer Arn. 6 3 In such cases the stomach was emptied and the volume of contents determined. All experiments were carried to completion except where otherwise indicated on the charts. Subjects showing any indication of pathological response were rejected. Free acidities are distinguished in charts from total acidities by using the prime mark as A’. Among the egg preparations tested were raw white, raw yolk, raw whole eggs (strained and unstrained), soft boiled, hard boiled, scrambled (with and without excess of fat), fried (with and without excess of fat), plain omelet, Spanish omelet, deviled eggs, poached eggs, pickled eggs, shirred eggs and soft cooked eggs. Frozen eggs and cold storage eggs were compared with fresh eggs. Duck and turkey eggs were also used as well as the Chinese preserved duck egg called pidan. Eggs with milk, French toast or eggs with bread, scrambled eggs with frizzled beef, and bacon and eggs were food combinations tested. A few tests were made on raw eggs with water and egg albumin with orange juice. 256 MILLER, FOWLER, BERGEIM, REHFUSS AND HAWK TABLE 2 _ Response of the normal human stomach to eggs prepared in different ways RAPID-TYPE INDIVIDUAL | SLOW-TYPE INDIVIDUAL Highest | Evacuation | Highest ‘BER Fie tanh bers hiaaea te Beaten acidity* time acidity* |Average Average Average} Average Hens’ eggs 1. a) Rawawhitessweerins. tee seers an oO 37 PARE A, AM Hoe bn FES AE GA BO eee Doe C 1:00 83 Si RaAwaw Mites ee rermec ss es elo LOO MesOn OOO Sa Raw, White ptee eee. ace ce cee 2:15} 2:15 | 6.0) 6.0 AA RAW: yO lkciee. ton tasers ronyciee en: ae ee 2:15} 2:15 | 941 94 PEGs wiRaw Wolke tone ow eh cha i 3:00 84 6 |Raw yolk 2:45 7 |Raw yolk 2 AR ee ee 2:00) 2:35 |105 | 95 8. “|Raw eggs.(whole): 3c...00. 50 2:15 107 9 |Raw eggs (whole)............... 3:30] 2:55 | 43 | 75 10 |Raw eggs (strained)............. 3:00 81 11 |Raw eggs (strained) >.2.-.%.'...- 3:10 Ho "|Raw eggs (strained) =. 2 .5....2.023- 2:15 80 13 |Raw eggs (strained)............. 200) 2335 |" wh" v7 14 |Raw eggs (strained) ............ 3:00} 3:00 | 53 | 53 1155. “Iiscortimloyorl eyole au easaodancceccan coaouleauo) 94 16a Sontpbowledsceececi seein eters leo 106 sa SOLG DOW it scco. tree ameter 2:30 68 iS MiSort: bovled4 sce. ence eee 63 iD Sort boiled’ 2255. {ac cee e oo 94 ZUM Solt) boilledsss-pec.seeeee eee 24 leon) 85 Divi Sott boiledieer ses eens ee 2:45 122 22.1 Sort, Doledsiestiaesmes a5 2s eee 2:50 2p AOOTt: DOU sno tone tase ene 3:00 79 mea | Sort, bolled cet e see eee eee 2:00 48 2D Olt DOME. ce ssoete ae ae eee 4:05 26) |Sott boiled: 4 2s. | sneer eee 3:30 58 O27 Sort. boned Sisbes ae eee 3:00} 3:00 77 £28) tard boiled’ 42.4. ten Load sb 12200 92 2, (Hard boiled... 3. .: aden Sane 132 *p0\ \Hard boiled. -.. 55.30.40 seater pe 82 20s [Hard boiled’... .-.-ee ee nie aU 101 S250" ard Worled st 4 eke ote Dae 2:15 70 ‘eer (Hatd boileds))74 109.2 ee SAS) 0) | 093) 2.85 Soa ielard boiled... sists alee: eee 3:15 34 4jHard boiled..... Beep ,35 3:30 MUELATdsbolleds sc. Ssh eee | GASTRIC RESPONSE TO EGGS 25 ~I TABLE 2—Continued RAPID-TYPE INDIVIDUAL | SLOW-TYPE INDIVIDUAL NUM- KIND OF ae ee Evacuation | Highest | Evacuation | Highest BER time acidity time acidity Average| Average Average] Average Some Lardebolledientmas iscce cere: 3:00 107 Sian Elard boiledve hiss ssc. sate 3:30] 3:20} 97 |102 2's) TS Cerra 0) £20 ec ae eae Pr 86 BOIMCLAMDICMN cs. 056 ode ssw oe coe (2lol 2:25:|100). 93. BOM PCTAMIDICG 2. oc lens see aw cee es 2:45 81 cA) TS eUeATinl of yc i SAA Ae et SR 3:50 22. USC nto] (is ae oe a 3:15} 3:15 | 94 | 85 SAMMI TACE Sete cys at o's cede «8 ais = ont ROO 106 SAME TIC ttc «Ged sited e ditties etieeo OL Qh 106 AA) LTT I GY gee ae 2:00} 2:00 |108 |108 46 |Fried (excess fat)...............|/2:45] 2:45] 91] 91 47 |Fried (excess fat)............... 3:00) 3:00 | 90 | 90 BoP Memeles PIA, 66 hic ges soe ee (OLS 83 49 jOmelet plain. ..)..0.....0825.....1/2:30) 2:25 | 80). 82 50 |Omelet Spanish.................|2:30} 2:30] 100} 100 51 |Deviled eggs.......... PRL 2:45} 2:45 | 103) 103 Bor woviled egPss.. oo... cs. bees 3:40} 3:40 my, OaChed Egrs. ..... 6... se cc's (LBOL LON 7117 PAISMORCRER OPTS: 5. 6 Woh. ce dee oh os 3:30} 3:30} 61 | 61 So, jobirred eggs. 2... 26s. . 04:.)....2(200), 2500)) 95): 95 PRP MPIIEEO: CP ES. 5. 5) oe be ten ee et 2:30) 2:30 | 85 | 85 ye EAS fa 51 lee) -nsa|2elole oom Onion St iBacon andveges..2cee. 4. -oe.oe ORE 85 |Frizzled beef and scrambled eggs.|2:30) 2:30| 67| 67 86 |Frizzled beef and scrambled eggs. 2:45) 2:45 |146 |146 87 |Chinese pidan eggs..............|3:15} 3:15 | 99) 99 88 |Chinese pidan eggs.............. 4:45| 4:45 | 30 | 30 89 |Raw hens’ eggs and water....... 3:15) 3:15 | 67 | 67 90 |Raw white and water........... 2:15) 2:15.) 85 | 85 91 |Raw white and orange juice..... TELS )\= Lel5o) SS86l. 286 92 |Raw white and orange juice..... 2a 2:15 |109 |109 * Acidities expressed as cubic centimeters of N/10 alkali required to neutralize 100 ec. of sample. Evacuation times and highest total acidities are recorded in table 2 which also gives average responses for individuals of the rapid- and slow- emptying types. The necessity for this division of subjects into classes is clearly apparent from an examination of the charts for certain of these individuals. Compare, for example, subjects Se and Da (figs. 1, 10 and 20) showing average evacuation times of about two hours for eggs with subjects Me and Ka (figs. 7, 19, 14 and 16) whose gastric digestion was not usually completed in three hours. Similarly the grand average evacuation time for 44 experiments on subjects of the rapid type was 2 hours 15 minutes and for 48 experiments on the slower type, 3 hours and 5 minutes. In order that comparisons of the digestion of eggs prepared in different ways might be made as direct as possible, several experiments were made GASTRIC RESPONSE TO Case,- Da 7, Frau Whites he $7. Sponge Coke Grae en) eon “9p Raed, thour 2h Sarg Fig. 1 pee Be Cases. #27, ~ to lUhites@) with 25000 Orange Juice (uh & ain Omelet (Os) 5 & & x 5 gS e x oe rat * — i $ g S rN 8 N: & a S ° eT hers Zz 3 Fig. 3 g ay nae Fra. $6 4 Whole ii pee 3, unkeaten; EB #0. w 8 eee, Fig. 5 00 “ho, HOH. iS 8 EGGS = &Y Ty 259 Sonar der is & Subrect,- CL 8 Fig Whites 1 hoor S0ce Orange Juice A Case. & 260 MILLER, FOWLER, BERGEIM, REHFUSS AND HAWK Case... Me. Subject. Ad. * Case /,9. Ai. ee £e98, un beaten{p) 5¢. Poached. & / Faw Bu with 250co,Distld Water. FR) 72. Soft Boiled 60 26. Piokled. (P) 9, Soft-Baled Eggs, 6) ui oo np KOH $ = & ae Ss So 8 ) g 3 ‘hour 2 hors 3 hours = Fig. 7 sl . Ss Subject. Mh. Cases,. 2,/2,/9,/130. CY el ee Cases. 3,//UL, 18,228. Zz Fas E sf, Pie @ bard Pho ad z 3. S. x 24 rons nen fags by) py Te holed eH 2/ tJ” ~~Se) 28 Plas'n Omelet FOr ‘ Subyect,. Se CaeeS,. 2/ 28, Z/ er epiegA £aa3,. (Se) 28, Alain Omelee (FOr) GASTRIC RESPONSE TO EGGS 261 73. Hard Boiled. Wy 57 Shirred, (3) g WE Fried, pee ae & 65 Bacon and Fags Ga) sts 9S © s : V, 2 Hand Boled Exgs; Borage? \ Pieaa Rh: : i ns Fee conrdzicer a by ase,. Harn. 17 Orn | ; 47, Fried, both siges (A 64 Bacon ant E7es (Ba) g 59, poe oo ce 4 hour Lhry Bhra Fig. 15 Subject. Mi Cases,. 39, //0 a - Pie ae Case,- /09.-Don:Clinese dan 30 Devilled £ags, (P) ARS S . 9h- =. Turkey Eggs, are boiled HOFaw Egg Whe (Fi) éo SEfoat Pelibiey, Fae. / etd : / —Tetal + Turkey. ag CA BESS 262 MILLER, FOWLER, BERGEIM, REHFUSS AND HAWK 8 Case Me P ee Fiat on oo wae Ee Trae Sage a / S Wa teed ep ae 2S nvee Dr mi + both vh s S fea Unie Py ead Ce, ten: oe er, : S38 3 Y 7’. 2 Se Stona ge Bits dt %Y Roos ee sage Esper ‘ Case, Gi Ae Pidan Bock) £98. (2) Fig. 21 Fig. 22 Su. — Cases - £/02029 Si Zz tes, with .\ ce Distld later (ul fe. SHtPr 20 Fred £e eB Pegi WAN 60 100 oc %o How & . ¥o i > . GASTRIC RESPONSE TO EGGS 263 upon most of the subjects used. About 75 of these experiments are charted in figures 1 to 23, which illustrate all of the most important facts brought out by this investigation. DISCUSSION The response of the stomach to raw eggs, raw white and raw yolk. In the experiments on raw egg white, the whites of three eggs were strained through cloth and given without any addition. This egg white left the stomach rather rapidly, i.e., in from 1 to 2} hours. (See table 2 and figs.1,2and17). In one case egg white showed hardly any stimulation of secretion, in another case the acidity was rather low, while two other cases showed a moderately high acidity. It appears that the stimula- tory power of egg white is insufficient to cause any material secretion in individuals of a low acid type while subjects who respond readily to most food stimuli will show a response to egg white. Thus in cases Do (fig. 2) and Mi (fig. 17) a distinct stimulation of secretion by egg white oc- curred, although the secretion was not nearly as pronounced as with most cooked eggs. The finding of Pavlov (2) that egg white produced no stimulation of gastric secretion in dogs cannot be applied to man without qualification. The experiment on egg white charted in figure 17 was repeated the following day but instead of withdrawing samples at 15 minute intervals the entire gastric contents were aspirated after 45 minutes. Twenty cubic centimeters of liquid with a total acidity of 42 and a free acidity of 18 were withdrawn. Of the original 100 ce. of egg white given, not 10 per cent remained. The bulk of the egg white thus left very quickly but not without giving rise to a secretion of gastric juice which continued for an hour longer. Where 250 cc. of water were given with the egg white (exp. 90, fig. 23) gastric secretion was distinctly stimulated, not more so however than is usual with water alone (6). The addition of 200 cc. of orange juice (expts. 91 and 92 and figs. 3 and 4) led to a distinct acid secretion and rapid evacuation of the stomach. Experiment 92 (fig. 4) showing an evacua- tion time of 24 hours for albumin with orange juice should be compared with experiment 34 on the same subject showing an emptying time of 3% hours for hard boiled eggs and experiment 41 on scrambled eggs which required 3 hours and 50 minutes to leave the stomach. The use of egg albumin with orange juice in the diet of invalids would appear therefore to be supported from the standpoint of gastric digestion. 264 MILLER, FOWLER, BERGEIM, REHFUSS AND HAWK In the tests on egg yolk the yolks of three eggs were given after being strained through cheese cloth. Egg yolk shows a distinctly different response from the white. The time required for gastric digestion is notably longer. For instance subject Do (fig. 2) required 1 hour for egg white and 2} hours for the yolk. Higher total and free acidities were also developed by egg yolk. The high fat content of egg yolk (33 per cent) may well account for the delayed evacuation. In one case more or less pathological and therefore not included in the present series, a high total but no free acidity was developed. The acidity in this case must have been due to the action of regurgitated lipase on the fat of the yolk. Two whole raw eggs were fed in certain cases. A number of tests were also made on such eggs after being mixed and strained through cloth. It might be expected that the response of the mixed white and yolk would be intermediate between that of yolk and white taken separately. It was found, however, that the response was much the same as that of yolk alone. In fact the average evacuation time for two whole eggs was greater than that for three yolks. Note the very similar response of egg and yolk on subject Ra (fig. 5). Note also the slower evacuation and higher acidity developed by whole raw egg as compared with egg white in the case of subject Da (fig. 1). Observe likewise the response of raw eggs as charted in figures 6, 7, 8, 9 and 10. The acidities developed (especially the free acidities) are lower than for most cooked eggs, but not markedly so. Soft boiled and hard boiled eggs. The ‘‘soft boiled” eggs were placed in boiling water for 33 minutes, the “hard boiled” eggs for 8 minutes. On the average the hard boiled eggs required a few minutes longer to digest than soft boiled eggs. Compare the two methods of cooking on subjects Mi (fig. 9), Se (fig. 10), Do (figs. 2 and 11), and note the simi- larity of response, in one case the evacuation times being the same, in another case the hard boiled having a slight advantage, while in the third the soft boiled left 15 minutes sooner. The acid response to hard boiled eggs was more marked in one case (fig. 9) but was the same as for soft boiled in the two other cases just mentioned. Comparisons of raw eggs with boiled eggs are found in figures 5, 9 and 10. In cases 9 and 10, raw eggs took distinctly longer than either soft or hard boiled eggs. Apparently the stomachs of the rapid-emptying type handle the cooked eggs more readily than raw eggs. Fried eggs and scrambled eggs. Scrambled eggs required on the average a little longer to digest than boiled eggs. Direct comparisons may be 4 GASTRIC RESPONSE TO EGGS 265 obtained from figures 2 and 11, showing scrambled eggs to take } to 4 hour longer to leave than either hard or soft boiled eggs; from figures 10 and 12, showing scrambled eggs to take 25 hours as compared with 14 and 2 hours for soft and hard boiled eggs respectively; from figures 5 and 13, which indicate that the boiled eggs had a very slight advantage; and from figure 23, showing scrambled and soft boiled eggs each to leave the stomach in 2? hours. The effect of scrambling the eggs with a large excess of bacon fat was tested in two cases. In one case (fig. 19) (that of a slow-emptying stomach) the response was similar to that for soft boiled eggs, while in the other case, that of a rapid-emptying stomach, the scrambled eggs with excess fat remained an hour longer in the stomach. Six tests were made on fried eggs particularly to determine the effect of frying on both sides with excess of bacon fat. This was done in view of the common opinion as to the indigestibility of greasy foods. Eggs fried in the ordinary way and not turned over left the stomach fully as soon as eggs cooked in any other manner. Compare experiments 21, 32, 40 and 45 on the same individual (fig. 23) showing evacuation times for fried eggs (2 hours), scrambled eggs (23 hours), for hard boiled (31 hours) and soft boiled (23 hours). Observe also figure 9, showing fried eggs to leave in 2 hours as compared with 24 hours for hard boiled and 2% hours for soft boiled eggs. When excess of fat was used the emptying period was somewhat longer than for shirred eggs (fig. 15) but not as long as for hard boiled eggs (fig. 14). It appears that an excess of fat may delay the digestion of eggs appreciably in individuals of the rapid- emptying type but has little effect in the case of slowly evacuating stomachs. The common opinion that fried foods are less digestible was not borne out in the case of eggs. We have previously shown that fried meats are readily handled by the stomach (7). Omelets, poached, shirred and soft cooked eggs. The digestion of plain and Spanish omelets was compared. Figures 10 and 12 show that the response of the stomach of this individual was identical in the two cases. The omelets required the same period of digestion as scrambled eggs and a longer period than hard or soft boiled eggs. That a plain omelet may remain in the stomach an hour longer than egg white with orange juice is indicated by figure 3. Poached eggs were found to leave the stomach in the same time as soft boiled eggs in the case of a rapid-emptying individual (see fig. 6) and to require a little longer in the case of a slow-emptying individual (fig. 7). Shirred eggs appear to leave the stomach more rapidly than hard boiled THE AMERICAN JOURNAL OF PHYSIOLOGY, VOL, 49, No. 2 266 MILLER, FOWLER, BERGEIM, REHFUSS AND HAWK eggs or eggs fried with excess of fat (figs. 14, 15 and 16) and belong with the more readily digestible forms of eggs. Soft cooked eggs appear also to be digested in medium time (expts. 61 and 62 and figs. 1 and 20). Pickled and deviled eggs. Eggs pickled in a vinegar extract of beets appeared to require about as long to digest as the hard boiled eggs from which they were derived (expts. 57 and 58 and fig. 7). Deviled eggs required 23 hours to leave the stomach as compared with 23 hours for hard boiled eggs and 23 for soft boiled eggs (figs. 9 and 17). Duck and turkey eggs, Chinese preserved eggs. Soft and hard boiled duck eggs and hard boiled turkey eggs were compared with hens’ eggs prepared in the same ways. Two eggs were given to each subject. A comparison of experiments 26 and 63 (figs. 7 and 19) and experiments 36 and 64 show that duck eggs were handled by the stomach in about the same time as hens’ eggs. This was perhaps to be expected from the similarity in composition of ducks’ and hens’ egg. Hard boiled turkey eggs were compared with hard boiled hens’ eggs in two cases. In the completed experiments (figs. 2 and 11) the subject Do required 2? hours for the turkey eggs as compared with 12 hours for hens’ eggs prepared in the same way. The difference is probably due to the larger size of the turkey eggs, whose contents weighed 77 grams each. The Chinese preserved egg called “‘pidan’’ was tried out in two cases. These eggs have dark greenish yolks and yellow brown “whites” of a firm gelatinous consistency and possess distinct odors of ammonia and hydro- gen sulphide. The period of retention of these eggs in the stomach we believe to have been influenced by their unappetizing character and in — one case at least (fig. 18) to a prejudice against them. In one case (fig. 18) a single egg only was given. This remained in the stomach for three hours as compared with 13 hours for hard boiled hens’ eggs (fig. 2). In the other case (figs. 13 and 22) two “pidan”’ eggs were given and remained in the stomach 42 hours as compared with 3 hours for hard boiled hens’ eggs. The composition of these eggs has been studied by Blunt and Wang who have also carried out tests on the digestibility of these eggs in vitro (8). We desire to thank them for supplying us with the Chinese eggs used in our tests. Cold storage and frozen eggs. An attempt was made to determine whether the keeping of eggs in cold storage for eight months had any effect upon their gastric digestibility when cooked in different ways. When the cold storage eggs were fried and compared with fresh eggs fried in the same way (figs. 15 and 21), it was found that both remained GASTRIC RESPONSE TO EGGS 267 in the stomach the same length of time and developed similar acidities. Another individual (figs. 2 and 11) evacuated hard boiled fresh eggs and soft boiled storage eggs in the same period (1% hours) and the highest acidity in each case was about 90. No differences in the responses of the stomach to fresh and cold storage eggs were demonstrated. The commercial frozen egg mixture was given to our subjects in the form of scrambled eggs and also made up into sponge cakes inasmuch as such eggs are mainly used in baking. Our two subjects who were given scrambled eggs both showed evacuation times a few minutes shorter for preparations made from frozen eggs than for the fresh egg prepara- tions. The acidities developed were also practically identical (figs. 2, 11, 5 and 13). Sponge cakes into which fresh and frozen eggs had been incorporated were likewise compared on two subjects, 100 gram portions being used. One of these comparisons is charted in figure 1. It shows a few minutes more rapid emptying where the fresh eggs were used but this difference is within the limit of experimental error. No appreciable differences in the action of the stomach on the two cakes could therefore be demon- strated nor does there seem to be any objection to the use of such eggs when canned under proper conditions. Eggs used in combination with other foods. Several popular combina- tions of eggs with other foods were fed to certain of our subjects and all were found to be readily taken care of by the stomach. ‘The combi- nations tested were: a, milk and eggs; b, bacon and eggs; c, French toast; d, frizzled beef with scrambled eggs. The egg-milk combination used was an egg-nog consisting of 1 egg, 7 cup milk, ? tablespoon sugar, + teaspoonful vanilla extract and a sprinkle of salt and nutmeg. This combination took a little longer than eggs alone in the case of one man of a high acid, rapid-emptying type (fig. 11) but hardly as long in the case of a low acid individual (expt. 80). The addition of eggs to milk distinctly alters the curdling effect of the gastric juice on such milk, the albumin preventing the formation of hard massive curds and giving rise to a light, flocculent precipitation of the casein. The French toast used was made from 85 grams of bread with 2 eggs and fried in bacon fat. This toast required a little longer to digest than _ bread and butter alone but no longer than 2 hard boiled eggs (figs. 14 and 16) and must from this’standpoint be considered as a satisfactory food. Two eggs with bacon required in one case (fig. 14) only a little longer than fried eggs alone, while in another case (fig. 15) the bacon and eggs 268 MILLER, FOWLER, BERGEIM, REHFUSS AND HAWK left half an hour sooner. Individuals vary in their response to fatty foods but it appears that bacon and eggs are handled at least as readily as other foods high in fat and protein. The frizzled beef and scrambled egg preparations used were made from 2 eggs with 25 grams chipped beef and a tablespoonful each of cream and butter. This chipped beef preparation took no longer to digest than scrambled eggs alone and gave rise to a more pronounced acid secretion (figs. 5 and 13). Meat-egg preparations would therefore appear to possess certain advantages over eggs alone. Eggs are distinguished from meats by the lower acidities which they provoke and by their more rapid evacuation. As examples of this note charts 15, 16 and 21, illustrating the digestion of roast lamb and boiled tongue as compared with eggs. The results presented in this paper should also be compared with our findings on meats as presented in preceding papers (7). The average of the highest total acidities for all egg tests was about 80, and for free acidities 60. Meats on the other hand showed an average total acidity of 125. The average evacuation time for subjects of the rapid type on beef and beef products was 2 hours and 35 minutes as compared with 2 hours and 15 minutes for eggs and egg preparations. Subjects of the slow-emptying type required on the average 3 hours and 25 minutes for beef as compared with 3 hours and 5 minutes for eggs. Pork required a longer time than beef. SUMMARY AND CONCLUSIONS A series of over 90 experiments on 18 different subjects was carried out to determine the response of the normal human stomach to eggs prepared in various ways. ‘Two eggs were used as the experimental meal except where otherwise specified. The fractional method of gas- tric analysis was employed. The evacuation times and highest acidities have been tabulated and curves plotted to show the comparative re- sponses of certain subjects to different egg preparations. The subjects were classified as belonging either to the rapid- or to the slow-emptying types. The average evacuation time for all egg prepa- rations was for the first class 2 hours and 15 minutes and for the second class 3 hours and 5 minutes. Eggs give rise to less stimulation of gastric secretion than meats and leave the stomach sooner. Beef, for example, showed an average emptying time of 2 hours and 35 minutes for the rapid- and 3 hours and 25 minutes for the slow-emptying type. The average of the highest GASTRIC RESPONSE TO EGGS 269 acidities developed in egg experiments was 80 as compared with 120 for beef. In general eggs show high combined acidities throughout the early period of digestion. Raw egg white left the stomach much more rapidly than any other form of egg preparation. A moderate secretion of gastric juice was in- duced in subjects of a high acid type, but this did not become apparent until most of the egg white had left the stomach without being acted upon by the gastric juice. Egg white with 200 ce. of distilled water produced a more marked stimulation of acid secretion. Egg white with 200 cc. of orange juice led to a distinct gastric secretion and a rapid evacuation of the stomach. Raw egg yolk required much longer to leave the stomach than egg white and higher acidities were developed. Whole raw eggs resemble egg yolk in their response whether unmixed or strained through cloth, showing the same delayed evacuation and greater acid stimulation as compared with egg white. Raw eggs produced somewhat less stimula- tion of acid secretion than boiled eggs and remained longer in the stomach. Hard boiled eggs required on the average a few minutes longer for gastric digestion than soft boiled eggs but the acid response was similar in the two cases. Scrambled eggs required a little longer to leave the stomach than boiled eggs. Fried eggs were handled as readily as soft boiled eggs or any other type of cooked egg. Eggs scrambled or fried with a large excess of fat remained in the stomach a little longer, the difference being most marked with the rapid-emptying type of individual. The belief that fried or moderately greasy foods give the stomach appreciably more trouble than others was not supported by our findings. The response of the stomach to plain and Spanish omelets was found - to be quite similar. Omelets remained in the stomach as long as scram- bled eggs and longer than boiled eggs. Poached eggs, shirred eggs and soft cooked eggs were found to be among the more readily digested forms of eggs. Eggs pickled in vinegar were digested in the same time as the hard boiled eggs from which they were prepared. Deviled eggs remain in _ the stomach a little longer than plain boiled eggs. The eggs of the duck and turkey are handled by the stomach in the same way as hens’ eggs, evacuation being somewhat delayed in the case of turkey eggs due apparently to their greater bulk. 270 MILLER, FOWLER, BERGEIM, REHFUSS AND HAWK The Chinese preserved egg called ‘‘pidan” gave rise to delayed and low acid responses in the stomach as well as delayed evacuation. This may have been due in part to the unappetizing character of these eggs. Cold storage eggs, whether boiled or fried, could not be distinguished from fresh eggs as far as the response of the stomach was concerned. The same was true of the mixed frozen eggs of commerce, whether these were scrambled or used in the baking of cakes. Eggs with milk, or egg-nog, leave the stomach a little more slowly than eggs alone, the egg albumin preventing the formation of indigest- ible curds in the stomach such as are likely to be formed with milk alone.. Eggs with bread or French toast remained in the stomach a little longer than bread and butter alone but not longer than hard boiled eggs. Bacon and eggs were taken care of by the stomach almost as readily as fried eggs alone while possessing distinctly higher food value. Frizzled beef with scrambled eggs were digested as quickly as scram- ‘bled eggs alone. Eggs and meat appear therefore to form a desirable combination from the standpoint of gastric digestion. The authors wish to express their appreciation of the codperation of the students of Jefferson Medical College, who kindly acted as subjects of these tests. BIBLIOGRAPHY (1) Beaumont: Physiology of digestion, 2nd Ed., Burlington, Vt., 1847. (2) Paviov: The work of the digestive glands, 2nd Ed., Philadelphia, 1910. (3) Bateman: Journ. Biol. Chem., 1916, xxvi, 263. (4) Penzoutpt: Deutsch. Arch. klin. Med., 1893, xiv, 535. (5) JAWORSKI AND GLUZENSKI: Zeitschr. f. klin., Med., 1886. (6) Berceim, Renruss anp Hawk: Journ. Biol. Chem., 1914, xix, 345. (7) Fisupack, Smita, LicHTENTHAELER, BERGEIM, REHFUSS AND Hawk: This Journal, 1919, xlix, 174. (8) Buunr anp Wana: Journ. Biol. Chem., 1916, xxviii, 125; and private com- munication to the authors. STUDIES ON THE BRAIN STEM I. REGULATION OF Bopy TEMPERATURE IN THE PIGEON AND ITS RELATION TO CERTAIN CEREBRAL LESIONS F. T. ROGERS From the Hull Laboratory of Physiology, University of Chicago Received for publication May 10, 1919 INTRODUCTION For more than a century the pigeon has been a favorite animal for physiological experiments involving the extirpation of various parts of the brain. Although the names of Rolando, Flourens, Vulpian, Munk, Ewald, Ferrier, ete., at once arise to mind in connection with such work, the interpretations of results are in many cases still in an unsatisfactory condition. One factor that in the past has not been properly appreci- ated is the one which is being emphasized by the new school of compara- tive neurologists, namely, that the anatomical relationships in the cere- bral lobes of the bird brain are not the same as in the mammals. All published data on this subject at present are rather fragmentary and the morphology of the pigeon cerebrum is a thing of doubt and difficulty. Furthermore it is a notorious fact that few careful anatomical studies have been made in connection with physiological studies on the bird brain. (A few experiments have been made in this direction by McKendrick and by Edinger, with the Marchi method.) A better statement of physiological experiments on the pigeon brain still awaits the analytic work of the comparative neurologist on this common laboratory animal. The attempt is being made by the writer to correlate the physiological and anatomical results of brain lesions in pigeons in a more exact way than has been done hitherto. Anatomical details are not considered in this paper aside from those of the great subdivisions of the brain. In order to illustrate more objectively the location of the lesions referred to, two figures are included of sagittal sections of the pigeon’s brain (figs. A and B). There will be published elsewhere a detailed account, in so far as this is possible with present histological technique, of the parts of the brain that seem to be functional after operation. 201 3 Fig. A. Sagittal section of pigeon brain very near the median plane. Stained with iron hematoxylin. Fig. B. Lateral sagittal section of pigeon brain. By the term decerebration is meant a section through the forebrain bundles between the striatum and the thalamus. A.c., Anterior commissure; Co., Cere- bral cortex; C.s., Corpus striatum (mesostriatum of Edinger); DmTh., Dorso- median nuclei of thalamus; F.l.d., Medial longitudinal bundle; H.s., Hyper- striatum (Edinger); L.f.l., Lateral forebrain bundle; M.f.b., Medial forebrain bundle; O.ch., Optic chiasma; O.l., Optic lobes; Olf.b., Olfactory bulb; Th., Thalamus. 272 STUDIES ON THE BRAIN STEM De In a previous paper on the hunger mechanism of the pigeon, the nature of decerebrate restlessness had to be considered. The writer there expressed the opinion that there seem to be variations of reflex excita- bility, a, in different decerebrate birds; b, in the same decerebrate bird at different times. This led the writer to make an extensive series of decerebrations to study the variations that followed in different animals when the attempt was specifically made to produce the same kind and extent of lesions in all cases. The results may be divided into three groups. The method of decerebration is described by the writer in this Journal (1). Birds which lived less than two weeks after decerebration. In this group the writer has records of twenty-four birds. Examples of their behavior follow. Bird 9. Lived 7 days. Nystagmus of head present, digestion seemed to be normal, feathers slightly fluffed. Great difficulty in maintaining equilibrium, stood on its claws with head and body drawn forward, or it fell backwards. Finally spread its wings and rested on its breast, tipped forward. Temperature sub- normal, falling as low as 27°C. Autopsy showed cranial cavity filled with a big clot and slight traumatism of extreme anterior and lateral parts of thalamus. Bird 12. General equilibratory disturbances, which might (?) be accounted for by a blood clot on cerebellum found at autopsy. Died second day after decerebration. Bird §. Feathers fluffed, no disturbances of equilibrium; listless in appear- ance, eyes always closed except when touched. No vomiting, no spontaneous movements. Lived ten days. Bird 16. Slight equilibratory disturbances, feathers flat, occasional violent forced flying movements directed toward the right. Vomiting. Lived 6 days. Almost every conceivable mixture of variations of this sort may occur —forced movements or immobility; feathers flat against the body or fluffed; nystagmus of head and distortion of neck; body temperature normal or subnormal; restless movements with crop empty and forced movements independent of the digestive conditions; birds become comatose and die. Decerebration with no visible damage to thalamus. The second group comprises nineteen birds in which there was decerebration with no dam- age done to the thalamus detectable by naked eye observation. This is the group of so-called typical decerebrate birds; birds which show no forced movements, body temperature normal, restless walking move- ments when the crop is empty, and a sleepy attitude the remainder of the time. These birds lived for periods varying from three weeks to eight months. 274 F. T. ROGERS Decerebration with visible damage to thalamus. The third group com- prises eleven birds in which there is decerebration combined with visibly distinct damage to the thalamus. These birds are commonly supposed to differ from the classic decerebrate bird only in the absence of spon- taneous movements. The birds of this group lived periods of time vary- ing from two weeks to three months. More detailed description of this group will follow later. Why these variations in physiological effects when the attempt was made to make the lesion identical in all cases? The interpretation given in the past has been that in different cases different reflex path- ways have been injured; that in the thalamus is a subcortical center from which nerve pathways arise or terminate that induce certain modifications of body behavior. In how far this is true is a question that, as Tigerstedt says, “‘cannot for want of critical attention be defi- nitely stated.” In part the suggested explanation may be true. There must be some anatomical basis of the differences observed but equally certain is it that one big physiological factor has been wholly omitted in the few considerations of the subject available. As will be pointed out in this paper, decerebration with simultaneous thalamic involvement leads to a condition in which the animal loses the ability to maintain and regulate its body temperature. With these variations in body tem- perature there is a marked change in reflex excitability of the animal so that, in part if not wholly, the behavior of the animal is dependent on its body temperature. To elicit information dealing with this phase of the subject it therefore became necessary to determine the factors responsible for the variations and regulation of body temperature. This therefore forms the first paper and the application of this to reflex activities will be given in the following one. TEMPERATURE VARIATIONS OF THE NORMAL BIRD The body temperature of the normal pigeon varies usually from 40° to 42°C. as measured in the cloaca. Occasionally it may be a trifle less or a trifle more. According to the writer’s tests the extreme limits may be considered as from 39.5° to 42.5°C. It is frequently observed that if the thermometer bulb be pushed beyond the cloaca into either the rectum or oviduct that the temperature of 43° to 43.5°C. may be re- corded and withdrawal into the cloaca is followed by a fall to 42° or 42.5°. It therefore follows that in any careful comparative measure- ments the thermometer bulb must always be inserted into the cloaca a STUDIES ON THE BRAIN STEM ANH constant distance for a constant time or always be subject to slight uncertainties. In the work here recorded because of this slight uncer- tainty the figures given at any time are always considered subject to a possible error of 0.5°C. The variations in the normal bird have been described specifically by several workers. Thus Feré (2) found the normal temperature to vary from 41° to 42°, falling slightly when the animal is quiet, sleeping or incubating eggs, and rising slightly with excess muscular or nervous activity. Furthermore he considered that there is a slight variation according to sex and age, being higher in the male than in the female and higher in the young than in the older bird. Simpson and Galbraith studied the diurnai rhythm and found it similar to that of the mammals. Hilden and Stenbick (3) have made a comparative study of the body temperature in various birds and confirm the statement of Simpson and Galbraith that, as a general rule, the range of diurnal variations is greater in smaller animals than in larger ones. They also state that by putting the birds in cages under artificial illumination the diurnal rhythm may be reversed and under such conditions the body temperature averages higher than in birds under normal conditions. The diurnal variations described may be readily confirmed and vary from 1° to 2°C. Variations with external temperature. Exposing a normal bird to extremes of hot and cold, still compatible with life, produces little or no change in the body temperature. Thus sudden changes in the tempera- ture of the bird’s cage, varying from 4° to 38°C. for periods as long as twelve hours produced no changes greater than those which may occur in the limits of the diurnal rhythm (fig. 1). The influence of starvation. Depriving the normal bird of food but not water for a period of five to seven days has little effect upon the body temperature. But during the second week of starvation the body temperature becomes subnormal, and after fourteen or fifteen days may be as low as 36°C. with the bird in a cage at the usual room tem- perature of 20° (fig. 2, A). During this stage of starvation the bird begins to lose its ability to maintain a constant body temperature and acts somewhat like a cold-blooded animal. Thus, at this time, exposure of the bird to cold is followed by a fall, and exposure to warmth is fol- lowed by a rise in body temperature. It is therefore possible by pro- longed starvation of the pigeon to reduce it to a condition in which its body temperature is, in part, a function of that of the environment. In all such experiments care has been taken that the starving bird shall always have plenty of water. Feeding the bird promptly brings the 276 F. T. ROGERS ge Se Horme! Bira [PERM SE YS RP ee EA FS Thalamic Cauterization. Decerebration + Thalamic Cavuterizetion ee sees = oK i ’ ‘ ' ' Saas Tempera Ture of Cages. ween e nw ne ey ) 1 ' Piavete Time in halg days Fig. 1° Time in 12 hour intervals as abscissae; temperature in degrees Centi- grade as ordinates. Temperature of cage in broken lines and of birds in continu- ous lines. Comparison of body temperature variations of four birds with the brain lesions indicated when all were simultaneously exposed to the atmospheric temperature variations of the cage indicated. 1, Normal bird; 2, bird with thalamic cauterization after partial decerebration; 3, normal decerebration, thalamus intact; 4, complete decerebration and thalamic cauterization. fern ae nnn e ne ene eee ee en me wee ee --- = -- ann we eee ee ene ee etl 1 ' t=- " ‘ ' 1 Degreest- Centigrade af u ' te 40 i Wormel Bird - Starvation 4 Time indays StTerveTion peyiod begins of K ana ends 2) Z : yf wy 10 Ings Ls tt a Pit = opecnn tr? Jes S < " Sitar — the “ it A) renee} ee pee an actor cm pee acme ng eteaeeneg i or tH ao He # An Average Decerebrate Bird -, (his bird lived 6 months) Fig. 2. A. Body temperature variations of a normal bird, deprived of food but given water. Time in days; temperature in degrees Centigrade. B. Tempera- ture variations of a decerebrated pigeon in which particular pains were taken to make certain that no part of the cerebrum remained in the cranial cavity. Thala- mus intact. Temperature of cage in broken lines; birds, in continuous lines. STUDIES ON THE BRAIN STEM 277 body temperature back to normal if, of course, starvation is not pushed until death is imminent. The influence of variations in water intake on the body temperature will be reported later. TEMPERATURE VARIATIONS AFTER CEREBRAL LESIONS Temperature studies on decerebrate birds have been carried out by Fredericq (4) and by Corin and Van Beneden (5). The former found that decerebration caused little or no disturbance of body temperature. The latter workers studied the diurnal variations and the carbon di- oxide excretion as an index of heat production. They found a possible diurnal variation of 2.2°C., extreme limits of variations in normal birds _ of 39° to 43.6°, and that after decerebration the carbon dioxide produc- tion per kilo body weight is practically identical with that of the normal bird. The writer’s first results were rather confusing. But it finally seemed to appear that the results obtainable could be divided into four groups as: follows: a. Traumatism and pressure on the hemispheres. b. Decerebration with careful preservation of the thalamus. c. Decerebration with thalamic lesion. d. Thalamic lesion with partial destruction of the cerebral hemi- spheres. Traumatism and pressure on the hemispheres. In a series of four birds the hemispheres were exposed and roughly pierced in several places by forceps until the base of the cranial cavity was reached. At the same time the longitudinal and transverse sinuses were sectioned. The skin was then sutured over the bloody mass so as to compel the formation of a heavy clot over the hemispheres and cerebellum in addition to the traumatism. In spite of this rough treatment no marked alterations in body temperature occur, nor does the bird lose its ability to maintain a normal body temperature with wide variations in the temperature of the cage (fig. 3). Thus in the case figured although the bird was exposed to a temperature of 5° to 10°C. for a period of twelve hours, there was a fallin body temperature of 2°, a fall within the limits of normal variation. Effects of decerebration. The results here reported are of those animals only which lived from one to five months after the brain lesion was made. The changes in body temperature after decerebration vary strikingly according to whether or not the thalamic nuclei are simultaneously 278 F. T. ROGERS damaged. Ina careful decerebration, avoiding excess hemorrhage and cutting through the base of the corpus striatum in such a way as to avoid direct traumatism of the diencephalon, it is found that the ability of the bird to maintain a normal body temperature in all variations of external environment is little or not at all affected (fig. 4B). The bird maintains a normal temperature when exposed to cold and when exposed to heat may exhibit a slight rise, but one still within the limits of normal variation. Two cases have been found after this type of operation where there is an immediate temporary rise in body temperature. This, when it occurs, is striking (fig. 4 B) but no cases have been seen where this rise is distinctly greater than the upper limits of the normal variations. This is in harmony with the recent results of Moore (6) on the rabbit. 7ime in days Fig. 3. Temperature variations of a bird after traumatism of the cerebral hemi- spheres. Temperature of the bird in continuous lines and of the cage in broken lines. LESIONS OF THE THALAMUS Decerebration with thalamic lesion. After a clean cut decerebration when the hemorrhage has been controlled, a clear view of the anterior and dorsal surfaces of the thalamus and of the third ventricle may be obtained. In a series of twelve birds a bilateral cauterization or trau- matism of the dorsal and medial parts of the thalamus was done with a hot, sharp pointed probe immediately after decerebration. The cautery was applied after a clear view of the structures was obtained, using the habenula and third ventricles as landmarks. After this proceeding the birds commonly die within a few days unless care is taken to keep them warm. In other words, the prospects of such birds living is better in the summer than in the winter if the birds are kept at atmospheric tempera- ture. If kept at a temperature of 25° to 30°C. they may be kept alive STUDIES ON THE BRAIN STEM 279 indefinitely, very much as other decerebrate birds. After the operation described, the bird is reduced permanently to a cold-blooded condition (fig. 4A). Its body temperature seems to be largely a function of the temperature of the external atmosphere. Under such conditions its temperature can be arbitrarily set at any level and kept fairly constant by controlling the temperature of the surrounding cage. The tempera- ture of the bird is not that of the cage, but averages 8° to 10° above it. By cooling the cage it is possible to throw the bird into a state of inac- Fig. 4. A. Temperature variations of a bird with combined decerebration and thalamic cauterization when exposed to variations of atmospheric temperature indicated by the broken lines. Time in days and temperature in degrees Centi- grade. 8B. Temperature variations of a good decerebrate preparation with no detectable trauma of the thalamus. Temperatures of birds in continuous lines and of cages in broken lines. tivity or immobility that superficially resembles hibernation. By raising the temperature of the incubator the bird is thrown into a con- dition of hyperpyrexia. The temperature may be thus raised to 45° or 46°C. and death soon follows. The extreme limits to which a single _ bird’s temperature has been pushed without death are 19.5° to 45.5°, a total variation of 16°C. The effects of these wide variations in body temperature on the behavior of the animal will be described in another report. 280 F. T. ROGERS Thalamic lesion with partial decerebration. The preceding facts sug- gested of course that there must be some kind of mechanism in the brain stem of the bird that regulates its body temperature. When, however, further attempts at localization were made, surprising results followed. If the two occipital regions of the hemispheres are removed, taking care to leave intact the large superficial cortical artery which runs over the anterior two-thirds of the cerebral lobes, and then the dorso-medial portions of the thalamus are cauterized, it is found that there is no appreciable alteration of the body temperature or in the ability of the bird to maintain a constant body temperature at all temperatures of the environment (fig. 5). 5, n) 2 & +h ao} 1 ' 5 t-% Hye Ss s-* 3 t ‘ & ry Face H ' : a 8 ra aa: Nie: est 4 air ‘ { H | orn = Sie ‘ ‘ 1 4 ‘ ‘ taal ME Sr, eee Meas xO Kee ee ! { Kos { ! tog Thalamic lesion — Partial deceresration - t ' f »-—> Fig. 5. Temperature variations of a bird with cauterization of dorso-median parts of the thalamus after removal of the posterior parts of the cerebral hemi- spheres. Temperature of bird in continuous lines and of the cage in broken lines. The result therefore is that the maintenance and regulation of the body temperature may remain nearly normal—a, after extensive trau- matism of the cerebral hemispheres complicated with subdural clots; b, after decerebration leaving the thalamus intact; c, after thalamic lesions leaving the anterior halves of the cerebral lobes in situ. On the other hand, a combination of decerebration and thalamic lesion reduces the bird to a poikilothermous condition. It therefore follows that in what is intended to be a simple decerebration, if there be temporary thalamic involvement, mixed results may follow as seen in the case of fig- ure 2B. This is characteristic of the average decerebrate preparation STUDIES ON THE BRAIN STEM a where great care is taken to make certain that all the cerebrum has been removed. There is a period following operation when the tem- perature is inconstant and varies with that of the environment, but gradually this stage wears off and the animal regains the ability to maintain and regulate its normal temperature. MINOR VARIATIONS IN THE DECEREBRATE BIRD Although the decerebrate bird can maintain a normal temperature several differences between it and the normal bird are evident. In the decerebrate bird the range of diurnal variation may be greater than in the normal bird. Thus in a decerebrate bird three months after opera- tion the body temperature during the course of the twenty-four hours varied from 39.5° to 42.2°, a variation of nearly 3°C. The normal bird put in extreme cold may react by a rise in body temperature of about 1°C. I have never seen this in the decerebrate bird. A decerebrate bird exposed to sharp variations in the tempera- ture of its cage may give corresponding variations in its body tempera- ture which are rather sharp although still within the limits of the normal variation (fig. 1). This the normal bird does not do. (Possibly this may happen during sleep. It has not been tested.) If there be any variation it tends to be compensatory in character, falling slightly on exposure to heat or rising when exposed to cold. Thus in a normal bird: TIME a pats me he TEMPERATURE OF CAGE degrees C. degrees C. 10 a.m. 42.3 22 2 p.m. 42.8 22 6 p.m. 42.0 22 10 a.m. 42.5 22 and raised to 30°C. 2 p.m. 41.0 30 then lowered to 22°C. 6 p.m. 40.5 22 7 a.m. 40.5 22 then lowered to 5°C. 2 p.m. 42.2 5 then raised to 22°C. The absence of this finer compensatory mechanism, quite variable indeed even in the normal bird, seems to be lacking in the decerebrate preparation. These finer reactions seem to be due to two simple facts. Sudden exposure of a normal bird to extreme cold leads to restless 282 F. T. ROGERS struggling which may readily account for the slight rise in body tempera- ture. On the other hand, exposure to heat (38° to 40°C.) leads to pant- ing and forced breathing. In the decerebrate bird under the same con- ditions, cold does not directly stimulate restlessness nor does heat lead to panting. These are important factors the loss of which accounts for some of the irregularities described. DISCUSSION A further analysis of these and other possible factors such as altera- tions of blood distribution and changes in the feathers will be published later. Some of the effects described might be attributed to “shock.” Shock, however, is a condition unknown in birds. Certainly, the corpus striatum may be removed without much change in body temperature regulation and equally certain is it that lesions of the thalamus which do not completely separate the hemispheres from the brain stem have little effect on the temperature regulation. It may be that in part the effects are due to altered circulatory conditions in the brain. The tem- perature alterations could not, however, be produced by pressure of blood clots alone on the hemispheres. ‘There is the possibility that dam- age to the third ventricle has led to alterations in the pressure relations of the cerebro-spinal fluid and this may produce changes in the medul- lary centers which play a part in the regulation. Or it may be a com- bination of changes in both the external and internal cerebral fluid media. SUMMARY The normal pigeon exposed suddenly to temperatures of from —4° to 38°C. is able to maintain its body temperature constant within the limits of the diurnal variation. Within these limits, exposure to cold may lead to a slight increase and exposure to heat a slight decrease in the body temperature. Prolonged starvation of the pigeon leads to a condition in which the body temperature becomes subnormal and rises or falls according to corresponding changes in the temperature of the external air. Feeding the bird when this stage has been reached quickly brings the body temperature back to normal. Two compensating factors in the normal bird which tend to maintain the body temperature constant in extremes of heat or cold are: excess muscular activity and rapid, forced breathing or panting. Neither of these two factors appears in the pigeon after decerebration. STUDIES ON THE BRAIN STEM 283 In the decerebrate pigeon with minimum damage to the thalamus, a normal body temperature is maintained in spite of variations of external temperature of from 5° to 388°C. Under such conditions the body tem- perature rises or falls accordingly, but only within limits of the normal diurnal variation. Decerebration and thalamic cauterization reduce the animal per- manently to a condition where the body temperature is in large part a function of the external atmospheric temperature. In such animals the body temperature may be lowered to 19°C. or raised to 46°C. by varia- tions of atmospheric temperature of from 10° to 38°C. This renders possible the production in the pigeon of conditions resembling hyper- pyrexia on the one hand, or ‘‘artificial hibernation” on the other. Lesions of the dorso-median grey matter of the diencephalon which do not completely separate the fore-brain from the mid-brain, produce little effect on body temperature maintenance or its regulation. BIBLIOGRAPHY . (1) Rogers: This Journal, 1916, xli, 555. (2) Fert: Journ. de la Anat. et Physiol., 1899, xxxv, 808. (3) HitpEeNn anp SternBAcx: Skand. Arch. f. Physiol., 1915, xxxiv, 382. (4) FrepEerica: Arch. de Biol., 1882, iii, 687. (5) Cortn AND VAN BENEDEN: Arch. de Biol., 1887, vii, 265. (6) Moore: This Journal, 1918, xlvi, 253. THE AMERICAN JOURNAL OF PHYSIOLOGY, VOL. 49, NO. 2 THE PHYSIOLOGICAL SIGNIFICANCE OF THE REACTION OF TISSUE CELLS TO VITAL BENZIDENE DYES P. G. SHIPLEY From the Osborn Zoélogical Laboratory, Yale University and the Anatomy Depart- ment of Johns Hopkins University! Received for publication May 10, 1919 Although the results of vitally staining living animals with the acid benzidene dyes are well known, and the distribution of the dye in the body has been carefully studied under normal and pathological condi- tions, until very recently little attempt has been made to show experi- mentally how the color enters the cells in which it is found or in what state it exists in the cell cytoplasm. As yet, none of the theories which have grown up about the origin and significance of the stained granules with which the cytoplasm of the ‘‘pyrrhol cells” is studded has been generally accepted, and none can be said to have been proven. Ehrlich (1) saw in the behavior of body cells toward injected dye solutions evidences of the existence of a specific chemoceptor, possessed by certain chromophil elements, which furnishes a bond between part of their cytoplasm and the stain. Goldman (2) concluded that the evidence accumulated in the course of his masterly series of experiments points to the demonstration by the dye of a secretory activity on the part of the pyrrhol cell. Tschaskin (3) believes that the benzidene dyes, isamine blue and trypan blue, color the mitochondria of the various trypanophil elements, and that the great dye masses seen in the clas- matocytes are the result of elaboration of a secretion granule by the chondriosomes of these cells: a secretion which is also stained by the vital azo dye-stufts. The most generally accepted theory in this country at present is that advanced by Evans and Schulemann (4) as the result of comparative experimentation with a large number of azo dyes. They believe that vital staining with dyes of this class is the result of phagocytosis by ‘It is a pleasure to express here my gratitude to Prof. R. G. Harrison for per- mitting me to use the Osborne Zodlogical Laboratory and its equipment and for advice and assistance which have been of inestimable service. 284 REACTION OF TISSUE CELLS TO VITAL DYES 285 special cells of ultramicroscopic dye particles, which, though apparently in molecular solution, exist in reality in a state of fine dispersion as an hydrosol. According to these authors any dyes which can be dispersed in particles sufficiently fine to pass readily through the blood-vessel walls are possible vital stains, and they have shown that the presence of multiple sulphonic acid radicles in the dye molecule is favorable to this condition. Dyes of this sort, when intrcduced into the circulation, pass out through the vessel walls into the tissues and invade them as a foreign body. As such, the dye is removed and segregated by a group of cells, morphologically different, but functionally united—a great scavenger tissue, the units of which Evans calls makrophages. Of course, neither the term ‘‘makrophages,’’ nor the word ‘“‘phagocytosis’”’ (by which Evans means the collection and segregation of the vital dye), are used within the limits assigned these words by custom. The dye particles are probably not engulfed by the process of protoplasmic flowing which is the ordinary conception of phagocytosis, and many of the cells which are ‘“‘trypanophil” are not phagocytes in the usual sense of the word. On the other hand, some of the cells which are most active in englobing bacteria and other coarse particles have under ordinary conditions no part in the segregation of vital dyes in the body of the living animal, e.g., the polymorphonuclear leucocytes.? Hoffman (5), working in Aschoff’s laboratory, has shown that if bits of embryonic liver were cultivated in the blood plasma of an adult animal, drawn immediately after an injection of trypan blue (plasma con- taining a large amount of dye in suspension) certain cells could be found in the new growth about the transplant which had in their cytoplasm larger quantities of the blue stain than did the majority of the new growing cells. These trypanophil elements were, he said, star-shaped, and the trypan blue existed in their cytoplasm as large masses or coarse granules, contrasting sharply with the fine blue granulations seen in the spindle-shaped ‘‘fibroblasts’”’ which formed the mass of his newly grown tissue. Hoffman believed the coarsely granulated cells to be young phagocytic endothelial cells descended from those which line the liver capillaries (Kupfer cells). 2In this connection it is interesting to note the description by Downey of vitally stained granules in lymphocytes and granular leukocytes in the blood in - doubly ligatured veins and about the site of injections of trypan blue. The author has seen vitally stained lymphocytiform cells in the circulating blood of frogs under pathological conditions. 286 P. G. SHIPLEY Now the possibility of staining cells intra-vitam, which can be kept growing under conditions which facilitate the observation of single elements over long periods of time, offers a unique opportunity for studying the reaction of living cytoplasm to the dye, an opportunity which no examination of sections and film preparations from the tissues of vitally stained animals can give. It should be possible to observe an unstained cell in such a culture, to watch the first appearance of color in the cytoplasm and to follow the process of staining until the color has reached its maximum depth and intensity and the individual masses their greatest size and number in the cell body. It should be possible to observe the formation of the vacuoles which can sometimes be seen about the colored bodies and such an examination should throw light on how the dye enters the cell and answer the vexed question as to whether or not the colored masses in the cytoplasm of the pyrrhol cells, after vital staining, are merely aggregates of pure dye or whether the dye-stuff stains a preéxisting cell structure. Should the latter be the case, it ought to be possible to identify this body and to determine its physiological significance. The technique of making cultures of cells in vitro has been so often described that it is unnecessary to go into it in detail here. These studies were made on the cells of chick embryos cultivated in plasma of healthy adults. The method of making the cultures was that devised by Harrison (6) and modified by Burrows (7), used almost exactly as the latter originally described it. The heart and liver were removed from chick embryos to Locke’s solution with a needle and Noyes iridectomy scissors, and cut into bits under the binocular microscope. The frag- ments, with a small amount of the saline solution, were then transferred to a sterile cover slip and covered with a thin layer of plasma. The cover glass was sealed over the chamber of a deep hollow slide with a ring of vaseline and the culture so made was incubated at a temperature of 39°C. The instruments, glassware, ete., used were previously sterilized, and sterile technique was observed throughout the operation. The plasma was handled in paraffined glassware and kept in an ice-salt freezing mixture. Great care must be used to prevent evaporation of fluids, since the consequent concentration interferes seriously with successful growth of the explanted tissue. The first cultures studied were made of somatic cells of the chick embryo in the plasma of blood drawn from an adult hen one minute after intravenous administration of a 5 cc. dose of a 1 per cent solution REACTION OF TISSUE CELLS TO VITAL DYES 287 of trypan blue. When this blood was centrifuged, a beautiful deep blue plasma solution of the dye could be pipetted off from the corpuscles at the bottom of the centrifuge tube. It was soon found, however, to be more convenient to introduce the dye into the culture medium after the latent period and the initial rapid growth of the explanted tissue had passed and the new growth had become more stabile in its new sur- roundings. In succeeding cultures a solution of the dye in isotonic salt solution was added to the plasma clot in which the culture was growing after growth was well under way. This operation was done when the cultures were twenty-four to forty-eight hours old, and was carried out by injecting the dye solution into the plasma medium from a very slender curved pipette passed through the vaseline ring which sealed the cover glass to the hollow slide in the chamber of which the cultures were growing. By the above described method, studies were made of the reaction of cells to the benzidene dyes, trypan blue, trypan red, Congo red, azo blue and benzopurpurin, to colloidal silver and manganese, to carbon gran- ules of various sizes and other particulate foreign material. Cell cul- tures were supravitally stained with brilliant cresyl blue, neutral red and janus green and studies were made of cells stained with mixtures of two or more azo dyes and various combinations of benzidene vital stain- ing and granule phagocytosis with supravital coloration. All the find- ings were controlled by observations on the living tissues of adult animals prepared for examination by appropriate methods. In the young cells which grow in a thin membrane or in individuals which have separated from the tissue mass in such a culture and wan- dered off on the cover slip, the protoplasm is spread abroad in a very thin sheet, and cells in this condition were selected for examination, since in those growing deep in the clot along fibrin strands the cyto- plasmic structures are crowded so closely together that it is difficult to make out detail in the mass. The cytoplasm of these young cells contains beside the homogeneous, clear nucleus with its one or more grayish nucleoli, fat droplets, mito- chondria and, in parenchyma cells from the liver, pigment and secretion granules. The central body, centriole, centrosomes, etc., cannot be seen as clearly as in the cells grown in salt solutions described by Lewis and Lewis (8) though their situation can usually be made out. Mito- chondria are small, grayish, refractile bodies of varying shape and size and in plasma grown cells they are usually filaments, straight or curved rods or small granules. They have the power of changing from one to 288 P. G. SHIPLEY another but they are only very slightly if at all motile in cells grown in plasma in contrast to the rapid, vigorous movements they make in the cytoplasm of cells planted in salt solution. They are selectively stained a beautiful blue green color by 1: 10,000 solution of janus green, a dye which quickly indicates the mitochondrial nature of a doubtful granule. Besides these bodies, cells in twenty-four hour plasma culture have another granulation which is sometimes impossible to distinguish in unstained cells from the granular forms of mitochondria. In these young cells there are very small granules which may or may not be seen to be surrounded by a small vacuole in the cytoplasm. They are very active at this stage and they move about in the cell freely, and very rapidly. They may dart along or across the cell, and may, after an interval of rest, return to their original position or they may go off in another direction. Frequently they travel along the length of the cell by short tacks from side to side. Movement is irregular and always jerky in character. Sometimes in the course of this movement, the vacuole enclosing the granule may be drawn out into a long thread which, when the granule comes to rest, reassumes its normal relation to it, or the thread may break and the vacuole round up without its granule, or the vacuole may disappear into the surrounding cytoplasm. I have never seen two vacuoles unite to form one. Now if one examines an older culture, say a forty-eight hour or sixty- hour one, a change in some of the cells is at once evident. Cells may be found whose cytoplasm is packed with large grayish bodies on which pressure has forced the most varying and bizarre forms. They may be round or oval or angular or indented in every imaginable way. Some- times the cells are full of them, sometimes a cell may contain only one or two. Sometimes in a single cell one finds all transition forms between the tiny motile granules seen in all young cells and the huge masses just described, and it is evident that the two forms are identical and that the large granules are the result of the growth of the small ones, though the large granules are non-motile and usually show no sign of a surrounding vacuole. These large granules are not contained in all cells. Many of - the mesenchymal elements up to the death of the culture never con- tain any but the small type of granules. On the other hand, transition forms between the two types may occur. The identity of these granules is further assured by the evidence of cultures stained supravitally with neutral red or cresyl blue. The motile granules and the large masses stain a brilliant red with the first named dye and a deep purple with the second. The vacuoles surround- REACTION OF TISSUE CELLS TO VITAL DYES 289 ing the small granules are colored rose-pink by cresyl blue and brick red by solutions of neutral red. Mitochondria of the active living cell are never stained by the above mentioned dyes but the mitochondria of a moribund or dead cell may be brilliantly colored by either. Even in supravitally stained preparations it is often not possible to see the vacu- ole about the large bodies; but some of these masses are found, at one side of which a narrow, stained, crescentic segment of the vacuole which surrounds the granule is visible. In other words, the vacuole is usually entirely filled by the swollen granule. The reaction of these structures to supravital stains is sufficient to identify them with the cytoplasmic vacuoles and neutral red granules which Lewis and Lewis (8) have described in tissue culture cells and which they once interpreted as a degenerative change in the cytoplasm. In cells grown in plasma, however, the granule is the prominent feature of the picture given by supravital staining, instead of being a tiny dot swimming about in a huge vacuole as it is in cells grown in salt solutions. This difference in size relation between the vacuole and the segregation granule which it encloses results from the difference in the media in which the cells are growing. Living protoplasm in a glyco-saline medium is on a diet which, while sufficient to support life for a time, is extremely poor in particulate matter. In other words, the cells in saline media are living in molecular solutions. Plasma grown cells, however, are growing in a medium rich in colloids of various sorts. -The signifi- cance of this environmental difference will appear later when the relation of foreign particles to the growth of the ‘‘neutral red”’ granule is made plain. The so-called ‘neutral red granules’? which the Lewises (8) have described have without a doubt the same physiological significance as the structure which they call the vacuole. Their neutral red granules are identical with the small type of neutral red granules which are found in plasma grown cells.’ If film preparations from the subcutaneous tissue of adult animals are examined, these same bodies may be found in all the connective tissue cells. They have the same appearance in unstained films and the reaction of the granule to neutral red and to cresyl blue is identical with that of the granules in culture grown cells. In adult tissues the large - granules are found almost entirely in the cytoplasm of the clasmatocyte: 3 Jn a later paper published in collaboration, Mrs. Lewis has established the identical nature of the vacuoles and neutral red granules which she and W. H. Lewis described previously in cells grown in vitro in saline solutions. 290 P. G. SHIPLEY the fibroblast, on the other hand, being characterized by the possession of the small variety; but in the connective tissue of the adult animal, as in cultures of embryonic cells, it may be extremely difficult to draw a hard and fast line between the two cell groups, and transition forms between the two extremes may sometimes be found. It is very evident that these granulations are the granules which Maximow (9) and others have described in connective tissue cells after supravital staining with neutral red, and there is no doubt that the stainable masses in these culture grown cells represent the vacuoles and granules on which Renault (10) has based his theory of secretion by the ‘“‘mode rhagio- chrine’’—the vacuoles and granules of segregation. That is to say, we have to do here with a differentiation in vitro of indifferent mesenchyme cells which form resting wandering cells or — clasmatocytes, and the differentiation is a process of elaboration of granules in the cytoplasm. When the cells are stained by the vital azo dyes, trypan blue, trypan red, etc., the primary diffuse stain in cells is soon localized and, after twenty-four or forty-eight hours, the segregation granules contain all the color. The entire segregation granule may not be uniformly colored at once. Often the stain is first seen at one side of the granule where it forms a narrow crescent of color which broadens until it makes nearly the whole of the granular mass; or the dye may come into the granule equally from its entire periphery, in which case the edge of the granule is seen in optical section as a colored ring. The different stages of these processes of staining of the segregation granule by the dye, account for the crescent and ring shaped granules of dye which have been described in the clasmatocytes of the subcutaneous tissue of vitally stained animals. All of the large granules in a single cell may not be colored at the same time. Sometimes a cell whose cytoplasm is merely a mass of granules of this sort will have only one or two which have been stained. The number of stained granules in a given cell, however, increases with the length of time the cell is exposed to the dye. The small type of granule takes the stain just as rapidly as the large. Colloidal metals like man- ganese and silver (collargol), when taken up hy living cells, are segre- grated and stored within segregation granules which they color. The possession of segregation granules is not confined to connective tissue elements. They are present in large numbers in the cytoplasm of various parenchyma cells, e.g., of the liver; and exhibit in this situa- tion the same staining reactions, thereby accounting for the blue granu- lations in the parenchyma cells of the livers of animals stained with REACTION OF TISSUE CELLS TO VITAL DYES 291 trypan blue. Most of these cells, however, are equipped only with small granulations of the fibroblast type. The nature of the segregation granule and the reaction of the living cell to the benzidene dyes are best understood after a study of culture grown cells which have been fed with India ink. If carefully filtered India ink is mixed with the plasma used as a culture medium, the clot has a light yellowish brown color and appears homogeneous when examined with the dry objectives. Even with the aid of the oil immersion system, the largest granules of ink are scarcely visible as tiny brownish bodies, and the smallest are so minute as to be beyond the range of microscopic vision. In twelve hours, however, cells growing in such a clot have gathered large amounts of ink and stored it. Black masses, evidently aggregates of multitudes of small granules of carbon, can be seen in the mass of segregation granules and in vacuoles which, though they contain apparently only ink aggregates, give the same staining reactions as those about the ordinary neutral red granule. The aggregation of submicroscopic carbon particles to form part of the segregation granule together with a study of the growth of the granu- lar mass in the untreated cell leaves no other alternative for the inter- pretation of the significance of the segregation granule than as a mass of ageregated foreign material which the cell has gathered and stored and to which it is constantly adding albuminous and other submicrons de- rived from the surrounding tissue fluids where they exist in the colloidal (emulsoid or suspensoid) state. Vital staining of cells with azo dyes is accomplished by the same process apparently by which the cell acquires and stores other substances in the colloid condition which are the material useful as food to the body as well as those which are mostly debris or actively injurious. The granule which stains intra vitam in the cell body is then the equivalent of the protozoan food vacuole and since the amicrons of the semicolloidal dyes are stored in it, we have in benzidene vital staining an index and a demonstration of a feeding and storage reaction on the part of the cells of warm-blooded vertebrates. The analogy between the ‘‘food vacuole”’ of the protozoa and the se- gregation vacuole and granule in the vertebrate cell is made very evident by staining amoebae and paramecium with solutions of trypan blue. _ After a varying interval the protozoan segregates the dye which has entered its cytoplasm, in preformed vacuoles which contain the chylo- monas or other food which the protozoan has surrounded. The chylo- monas may be seen unstained in or beside the aggregated mass of trypan 292 P. G. SHIPLEY blue which grows larger as the animalcule remains in the dye solution. Moreover it is a matter of common knowledge that the vacuoles of the protozoan and the contained food mass are selectively colored intra- vitam by neutral red, and Loele (11) has called attention to the fact that both acid and basie dyes color the ‘‘oxydasekugeln”’ or nourishment vacuoles of paramecium. J may say here that the food vacuoles of amoebidae give the same reaction with brilliant cresyl blue 2B which characterizes the segregation granule and vacuole of the cells of warm- blooded vertebrates, and that a detailed study of these dye reactions in protozoa 1s now well under way. Large granules of carbon and coarse granules of the high molecular dye-stuffs which gain entrance to the cytoplasm may become part of a preéxisting segregation granule in the substance of which they may be found embedded, or if they are of sufficiently large size, one or several may be found enclosed in an “inclusion”? vacuole which has the same functional significance as a locus for the storage of dye-stuffs and other foreign material as the spaces about those granules of segregation which are visible in the untreated cell. The living cell deals in exactly the same way with bacteria, algae, fat droplets, red blood corpuscles, free pigment, ete., which it has engulfed in its cytoplasm, and it is possible to find in a cell, vitally stained with trypan blue, masses of the azo dye in the same ‘inclusion vacuole” which contains coarse particles phagocytized by the cell, whether those particles are some extraneous foreign granules like cinnabar or a cellular entity like a red blood corpuscle. Just so we may find pigment and the remains of red blood cells in the masses of trypan blue. It is well known that basic dyes like neutral red will stain the so-called ‘inelusion vacuoles” about phagocytized material and will after a time color the inclusion itself, just as food masses and the fluid in the food vaculoes of protozoa are tinted by the same dye. How far fetched are the attempts which have been made to establish a functional differ- entiation of the neutral red staining granule of the cell’s cytoplasm from the food masses and ‘‘inclusion’”’ vacuoles on the basis of slight or imagi- nary differences in color tone after staining with neutral red will be at once evident when we remember that the shade of the neutral red stain may vary in the food vacuoles of the different protozoa and those of the higher metazoan forms whose gastro-intestinal epithelium still retains a recognized intracellular digestive function. In these lower forms the zoologists recognize the tone differences after supravital staining as due to variations in the chemical composition of the digestive fluid in the REACTION OF TISSUE CELLS TO VITAL DYES 293 vacuole and the food mass (e.g., variations in amount of acid) but no one would venture to deny for these structures a fundamentally similar func- tional significance. Careful study of living cells in cultures and in the body of the adult animal and their behavior toward dyes and other organized particulate material shows conclusively that the ‘inclusion mass” and “‘segregation granule” are physiologically identical. In short, all sorts of material which the cell allows to enter, or takes into, its cytoplasm, eventually finds its way into some of these vacuoles of segregation and becomes an integral part of the contained granule. Certainly this is true of particulate substances, and since the subcutane- ous injection of distilled water is followed by the appearance of large fluid filled vacuoles in the connective tissue cells apparently identical with those which appear in cells grown in saline media, it seems likely that ingested fluids and solutions may meet with the same treatment in the cytoplasm. Again, some of the protozoa, for example paramecium, are able to concentrate or aggregate the relatively small molecules of phenolsulphonephthalein in their food vacuoles and to retain it for a considerable time under certain conditions. The aggregation of ultramicroscopic granules of carbon into the neu- tral red body effectively disposes of the necessity of considering the possession of a dyeceptor by these bodies, to account for their coloration by pseudo-solutions of azo dyes. Even without the evidence for me- chanical mixture which is offered by the incorporation of the inert carbon particle in the substance of the segregation granule, it is difficult to think of the gradual progressive process of granule staining by these dyes as the result of chemical combination of the dye with granular sub- stance. Nor is it possible to credit these granules with the possession of a multitude of chemoreceptors capable of binding a range of sub- stances from carbon to trypan blue whose molecules present the most diverse structure and among which there is not the least shade of chemi- eal relation. The exact mechanism by which the cell takes the tiny particles in colloidal suspensions and pseudo-solutions into its cytoplasm is still uncertain; but it is not at all difficult to suppose that we are merely dealing with another manifestation of well-known physico- chemical phenomena. The cytoplasm of the animal cell is almost universally recognized today as a colloid system and it is well known that such systems allow the entrance into and sofution or dispersion in their dispersion means of substances whose particles have become adsorbed on the system’s surface. Such an adsorption of amicrons of dye onto the surface of a cell bathed in a dye solution is only what is to 294 P. G. SHIPLEY be expected in the light of the Gibb’s law that substances in solution collect at interfaces since surface concentration tends to diminish free energy at such interfaces and under these conditions the adsorption of the disperse phase of a colloid sol is bound to follow.4 Under certain conditions this process may be actually seen to occur in tissue cultures. Collargol hydrosols are apparently toxic to the cells of chick embryos in culture and the silver gains access to the cytoplasm only with extreme difficulty. After a short time the bodies and proc- esses of cells which have been treated with the silver colloid may be seen entirely covered and completely outlined by a thick coagulum of adsorbed silver granules. Included in the cell’s cytoplasm, the segregation of dye particles into the vacuole of segregation probably follows along the same lines, for we must remember that the protozoan ‘‘food vacuole” and the vacuole of segregation in the vertebrate cell are really no more and no less than fluid droplets, and that where their surfaces are in contact with the cytoplasm we have again an interface between two fluid systems. In vitally stained paramecium, one can sometimes see colored granules concentrated about the food vacuole before the color enters the fluid globule, in which the animal’s food undergoes digestion. In this con- nection it is interesting to note the relation which seems to prevail between the motility of these food masses and that of the cytoplasm. In amoebae, whose cytoplasm is constantly and rapidly flowing in all directions, the food vacuole is passively moved about as the cytoplasm flows past. In the comparatively sluggish current of the protoplasm of the paramecium the food vacuole moves slowly over a route which ex- poses it at some time during its journey to the entire cell body. In the quiet cytoplasm of the cells of higher. vertebrates, however, until move- ment is automatically mechanically checked by distention of the cyto- plasm with masses of stored foreign material, the segregation granule is constantly rapidly and independently motile, and each one on its excur- sions covers a large part of endoplasm of the cell. It seems hardly neces- sary to point out the importance of the motility of the granule as an aid ‘ Evans has brought again to our attention a point in the morphology of the pyrrhol cells which was emphasized by Metchnikoff very early in his studies. If these cells are examined during life their periphery may be seen to be covered with tiny spine-like processes of the hyaline ectoplasm which are constantly and rapidly protruded and retracted—tiny pseudopodia. The constant changes in the surface of a cell whose ectoplasm is exhibiting this sort of movement and the re- sultant increase in the surface available for adsorbing particles must tremen- dously increase the absorbing capacity of the cell. REACTION OF TISSUE CELLS TO VITAL DYES 295 to the aggregation into its substance of particulate matter which has passed through the cellular ectoplasm, since by this means the granule wanders over a large portion of the cytoplasm collecting foreign sub- stances as it goes, and, as it were, combs the cytoplasm for the food which protoplasmic currents bring to the vacuole in the amoeba. Once in the vacuole the growth of the segregation granule becomes merely a matter of coagulation of amicrons to microns and the adsorp- tion of dye granules on each other or on albuminous or other phases which are dispersed in the vacuolar fluid in the same way in which two or more small granules in a single vacuole may be seen to unite to form one. There are no doubt two factors which aid greatly, if indeed they are not entirely responsible for the aggregation of the component particles in the segregation granule—concentration of the colloid in the vacuole by constant accumulation of freshly absorbed particles and by reimbibition of water into the cytoplasm, concentration which alone is sufficient to cause aggregation of the disperse phase in a sol, and as Schulemann (12) has shown experimentally, the presence of electrolytes in the fluid in which the amicrons are dispersed. All of these colloidal dyes are more or less precipitated in the presence of electrolytes in solution. While the above description is an attempt to picture the course of events which result in the vital staining of a cell by an acid azo dye- stuff it holds also for the process by means of which the cell stores up colloidal proteins and other finely divided materials useful in the meta- bolic processes of the body. Moreover it is questionable whether stain- ing with the ‘‘basic dyes” is always the entirely different process which Evans calls it and which at first glance one might believe it to be. Let us take, for example, the staining of the living cell by neutral red. This staining follows the same course in the cell as coloration by one of the benzidene dyes or metallic colloids. A diffuse, gradually increasing cytoplasmic stain is followed by the collection of the dye in the segre- gation granule and it is only the death of the cell which releases it to stain the nucleus, nucleoli and mitochondria. The same is true of eresyl blue. We have seen previously that even molecular solutions may be concentrated in the fluid surrounding the segregation granule and neutral red is probably not absolutely a molecular solution if its _ slow diffusion rate (13) may be taken as an indication, and furthermore neutral red may be precipitated from solution by salts. This dye probably hovers somewhere in that indistinct region between the colloid state and a state of true solution, and its sols probably represent 296 P. G. SHIPLEY very tiny particles rather than dye molecules suspended in the disper- sion means. Of course many dyes like janus green® beside entering the segregation vacuole color specific granules in the cytoplasm, and these phenomena, equally of course, are probably of an entirely different nature. But whether they result from a true chemical affinity or from some other cause, we have not yet been able to decide. Again the story of the colloid’s existence in the cell is not finished with its aggregation with the food mass, but it often undegroes chemical changes from inter- action with substances in the fluid about it, e.g., the metachromasia which follows aggregation of Congo rubin (Schulemann). At all events the individual granules are certainly segregated in pre- formed vacuoles, where, by aggregation to like granules and other material, they form the neutral red staining body of the authors. In this way particles of the vital azo dyes are mixed with the segregation granule and color it. They can be said, therefore, to stain a previously existing structure, though the staining is not by a chemical union with a part of the granular molecule but a mixture with the granular substance. It is very difficult to say with certainty whether or not new vacuoles are ever created in a cell to care for ingested dye-stuffs. That such a process occurs in caring for finely divided particulate matter is doubtful. It is possible that the segregation granule in some of the vacuoles may be > Tam not prepared to say what the factors are which govern the rate of absorp- tion and segregation of dye-stuffs by the living cell or the quantitative and quali- tative relation of the storage of ingested foreign material. Certainly the rapidity of absorption is not determined by the osmotic pressure of the solutions in contact with the cytoplasmic interface. Trypanred, a dye which is rapidly and readily dif- fusible is not stored by the cell in appreciable quantities until several hours after its exhibition, while brilliant cresyl blue, which hardly passes at all through semi- permeable membranes in four and twenty hours, stains the segregation granule of exposed cells in a few minutes. Moreover, when cells are exposed to trypan blue sols metachromatic granular staining is rarely seen, although this dye is not a distinct entity. Two colors may be separated by diffusion experiments from its sols, one blue, which diffuses slowly, the other, a red, and rapidly diffusible dye. These two colors may represent chemically distinct substances; on the other hand, and this is much more probable, trypan blue may belong to that class of substances described by Michaelis which forms hydrasols in which the degree of dispersion is multiple (polydispersoid). Staining with weak solutions of neutral red is a comparatively slow process but intense coloration of the segregation granule follows almost instantly on the exhibition of a concentrated dye solution, but concentration of solutions of dyes of the benzidene series has no appreciable effect on the rapidity with which vital staining takes place. Consideration of the reason of these facts must suit foramore complete understanding of physico-chem- ical phenomena, especially those which have to do with adsorption. REACTION OF TISSUE CELLS TO VITAL DYES 297 made up almost entirely of the dye substance after prolonged feeding with pseudo-solutions of the benzidene colors but it is more probable that the dye is present only mixed with other ingested material. Nor is it well to ignore the possibility that some of the dye may be taken into the cell as an adsorption compound with albuminous or other particles which are always entering the cell from the body fluids. So many of these vacuoles exist in the cytoplasm of a normal cell that it is not neces- sary to assume that new ones are created to care for injected dye, and besides the large vacuoles filled with swollen granules of segregation, there is always a reserve of tiny vacuoles which are capable of swelling to care for a condition of overfeeding. We know, however, that when large foreign bodies are ingested, they are enclosed in a fresh vacuole formed during their engulfing. It has been already pointed out that such a vacuole is identical physiologically with the other segregation vacuoles normally found in the cells, and it has been shown above that the relationship is at once made evident by subsequent feeding with vital dyes the aggregates of whose amicrons may be seen segregated in the “inclusion vacuole” along with the englobed body whose ingestion brought it into being. Combination of intra-vitam staining with an azo dye, for example trypan red, with supravital coloration of the mitochondria by means of a solution of janus green, demonstrates in a most striking manner, the distinct individuality of the two sorts of granules; and the same result may be obtained by staining growing cells simultaneously with janus green and neutral red. The mitochondria are not colored by the red dye, which stains the segregation granule, but are specifically stained with janus green. No relation has been observed between mitochon- dria and segregation granules and they are apparently distinct through- out the existence of the cell in spite of the assertions of Tschaskin (3), Levy (14) and Maximow (15) to the contrary.® 5 T have seen, however, in active, vigorously growing cells, when first exposed to isamine and trypan blue, distinct staining of the mitochondria, which is not permanent. The dye soon leaves these tiny bodies to enter the segregation vacuole and the mitochondria are, in a short time, left colorless. This phenome- non must not be confused with the preagonal staining of mitochondria of moribund cells by solutions of benzidine dyes by which they are surrounded. In such cells the first evidence of impaired vitality is coloration of the mitochondria. This is followed by staining of the nucleoli and the precipitation and staining of a ‘‘chro- matin network’’ in the nucleus. The tone gradually deepens and becomes homo- genous throughout the cell body, which rounds up, shrinks and finally degenerates into a mass of granular debris. What the meaning of the primary mitochondrial 298 P. G. SHIPLEY If a culture of cells grown in trypan blue is supravitally stained with neutral red, the blue granules take the red color also and become purple, then violet, then red, as the red dye becomes optically stronger than the blue. Staining of cells with mixtures of trypan blue and trypan red results in the presence in the cells of red granules and blue granules and granules stained violet or purple, as a result of a combination of different amounts of the two stains. It is not necessary to assume the possession of different chemoceptors for different dyes to explain this phenomenon. Since coloration of the segregation granule is due to the presence of dye granules in a mechanical mixture, the tint which the granule assumes _ after mixed color feeding depends only on the number of dye granules of each kind which happen to be poured into the same vacuole. Since all sorts of materials which the cell ingests find their way into vacuoles of segregation, it is of course in these vacuoles that the intra- cellular digestion processes with which we are familiar must be carried on—the lysis of red blood corpuscles, bacteria, etc. The vacuole which originally probably contained only the segregated fluid which the cell had absorbed, apparently serves as a sort of cell stomach, an or- ganulum in which the preparation of various materials capable of serv- ing the cells in their amabolic processes takes place. We may think of the vacuole as a fluid globule into which the various secretions of the cytoplasm are poured, to act upon the mass of the segregation granule within, or upon specific substances which the cell may have swallowed and passed into the fluid globule which is the vacuole of segregation.’ In these tiny stomachs, materials useful to the cell may be selected and separated from poisonous or useless matter, to be reabsorbed as food by the cytoplasm or passed on to other cells for nourishment or to build staining may be I cannot say but an analogous process apparently goes on in some animal and plant cells under normal conditions since these granules may be found brilliantly colored by various natural pigments, such as anthrocyanin and chloro- phil which has led some authors to use the term ‘‘chromochondria”’ to describe them. (AsvadourovaN. Arch. d’Anat. Micr., T.15, pp. 153-314). It is doubtless this sort of staining which has led Levy and others to believe that the segregation granule is the result of a mitochondrial metamorphosis, 7 There can be little doubt, moreover, that just as many drugs and other sub- stances (e.g., morphine) are, after absorption through the gastric or intestinal mucosa, reéxcreted into the gastro-intestinal tract, so waste products of cyto- plasmic metabolism may find their way into these vacuoles of segregation as well as into the surrounding fluid of the tissue spaces, for it is hardly conceivable that the cell should instantly differentiate between one substance and another of like physical properties in solution. REACTION OF TISSUE CELLS TO VITAL DYES 299 secretion. In this connection it is interesting to note that reabsorption of material into the cytoplasm of these pyrrhol cells can be shown to occur experimentally. If the phagocytic cells are fed with emulsions of fat or oil stained with Sudan III, the droplets of fat which are taken into their cytoplasm gradually grow paler and at length may lose their color entirely. If this process is allowed to continue uninterrupted, finally all the stain may be removed from the foreign oil and is found coloring the normal fat in the body of the injected animal. This course of events is followed even though the injected oil is an indestructible compound like the petroleum oils of the naphthene series. How far the destruction of fat-laden phagocytes may aid in producing the final effect cannot be told but the growing pallor of the droplets enclosed in the cytoplasm of healthy cells is a certain indication of reabsorption of the dye from the engulfed oil into the cytoplasm of the cell itself, just as is the staining of the animal’s own fat sure proof that the dye is given off from the phagocytes to the animal’s body. The waste is after a time cast out again as débris into the surrounding tissue fluid or freed in toto together with food products by the destruction of the short-lived and fragile cells which contain them. Therefore, inasmuch as the vital benzidene dyes are deposited in these organs, the colored masses in the clasmatocytes, etec., after injections of these colored pseudo-solutions, in a way, are also an index of secretory activity on the part of the stained cell as Goldmann and students of the French school have suggested. The power to carry on these processes is in some degree common to all cells since even the nerve cell contains vitally stainable granules, but certain elements—the Kupfer cell, the clasmatocyte, etc.—are especially active in this direction, and it is probable that we must consider these as a primitive cell type nearly related to unicellular organism. The degree to which the body cells which are not under ordinary conditions included in the class to which the clasmatocytes belong are called upon to perform these phagocytic functions is variable and is controlled by factors of which as yet we have a very imperfect comprehension. Cells of the same type in different animals will manifest very different reac- tions toward materials in the colloid state introduced into the animal’s circulation. For example, Wislocki has found that the liver cells of dog-fish will store amounts of trypan blue as large as those found in the cytoplasm of the Kupfer cells, while the liver cells in Cyprinidae after the same treatment contain no traces of the dye whatsoever. 8 Shipley and Cunningham, and Cunningham and Wislocki unpublished. THE AMERICAN JOURNAL OF PHYSIOLOGY, VOL. 49, NO. 2 » 300 P. G. SHIPLEY Again under conditions which vary from the normal any cell may be called upon to exercise a latent potentiality for ingestion, storage and digestion, as the lining cells of the blood vessel which normally refuse trypan blue or take it only in small amounts, will, following embolism, revert, functionally speaking, to a primitive type and engulf large quantities of dye-stuff (16). We are most familiar with the pathological physiology of the ‘‘pyr- rhol cells’’—their ability to destroy bacteria and other invaders which they have ingested, their relation to malignant neoplasm and parasitic cysts. Their importance as collectors of extraneous matter and the part they play in the organism’s defensive reaction against foreign bodies is well recognized but we are still much in the dark as to their role under normal conditions in the everyday life of the body. In reactions to pathological stimuli, we are dealing only with an exaggerated manifes- tation of a normal physiological digestive reaction which has been only slightly modified to meet an emergency (formation of giant cells, etc.). To dismiss these cells as scavengers is to do them an injustice, for how- ever important this function may be, their service to the body is a far greater one. Most of the material which the blood and lymph streams carry to the body passes through their hands and is stored and it may well be prepared by them for the more highly specialized cell which is to be the ultimate consumer. They are able to carry on in the body true intracellular digestion perhaps by means of a ferment (the makrocytase of Metchnikoff) analogous to the amoebodiastase which Mouton (17) isolated from cultures of amoebae. Recent studies have shown that these cells are capable of carrying on complicated chemical reactions such as the liberation of iron from hemoglobin and they are extremely active in the ingestion and storage of foreign fats, pigment, etc., which come to the tissue via the blood stream. The localization of specialized cells of this class in large numbers along the course of the blood vessels gives them easy access to incoming food-laden fluids and their close relationship to the vascular channels facilitates the disposal of waste which they have winnowed out and liberated from their cytoplasm, or which escapes together with stored food after, the destruction of their bodies. Material which has escaped these adventitial cells is seized upon and ingested by the great pyrrhol cells which wander about in the tissue spaces of the body or by specialized ‘‘nurse cells” like the makro- phages of the testis, in various body organs. Cells of this class receive from the tissue fluids all sorts of ‘‘raw”’ food material which they prob- ably pass, changed and purified by their secretions, to cells less able to perform digestive and selective functions. REACTION OF TISSUE CELLS TO VITAL DYES 301 BIBLIOGRAPHY (1) Esruicu: Brit. Med. Journ., 1913. (2) GoLpMANN: Beitr. z. Klin. Chir., 1909, Ixiv, 192. (8) TscHaskin: Fol. Haem., 1912, xiv, H. 3. (4) EVANS AND SCHULEMANN: Science, N. S8., 1914, xxxix, no. 1. (5) Horrman: Fol. Haem., 1914, xviii, H. 2, 137. (6) Harrison: Journ. Exper. Zodl., 1910, ix. (7) Burrows: Journ. Exper. Zodl., 1911, x, no. 1. (8) Lewis anp Lewis: Amer. Journ. Anat., 1915, xvii, no. 3. (9) Maximow: Arch. f. Mikr. Anat., 1906, Ixvii. (10) Renautt: Arch. d. Anat. Mier., 1907, ix, Fase. ili-iv. (11) Lorxe: Fol. Haem., 1913, xiv, H. 3, 308. (12) ScHULEMANN: Zeitschr. f. Exper. Path. u. Therap., 1915, xvii, H. 3. (13) TraGuE AND Buxton: Zeitschr. f. Physik. Chem., 1907, lx, 469. (14) Levy: R. Accad. d. Lincei, 1916, xxv, 8S. 5 a. (15) Maximow: Arch. Russes. d. Anat. d. Hist. et d’Embryol., 1916, i, 1. (16) Batcuetor: Proc. Amer. Assoc. Anat., 1914, Anat. Rec., 1914, viii, 139. (17) Mouton: Compt. rend. Acad. d. Sei., 1901, exxxiii, 204. STUDIES ON THE NERVOUS CONTROL OF THE KIDNEY IN RELATION TO DIURESIS AND URINARY SECRETION! I. Tae Errect or UNILATERAL EXCISION OF THE ADRENAL, SECTION OF THE SPLANCHNIC NERVE AND SECTION OF THE RENAL NERVES ON THE SECRETION OF THE KIDNEY E. K. MARSHALL, JR. anp A. C. KOLLS From the Pharmacological Laboratory, Johns Hopkins University, Baltimore Received for publication May 28, 1919 One of the authors, Marshall, in collaboration with Davis, found that the complete removal of the adrenals in cats leads to an impairment of kidney function. This is signalized by a rise in the urea content of the blood to about twice its normal value, and a much diminished rate of excretion of urea and creatinine in the adrenalectomized animals com- pared to the normal, when the kidneys are subjected to increased work by the injection of a mixture of urea, creatinine and sodium chloride. Moreover, these changes may occur with a normal blood pressure and at a time when the cats are in excellent physical condition. It was sug- gested that these results indicated the secretion of some substance by the adrenals which is necessary for the maintenance of normal renal activity (1). The recent work of Addis and his co-workers (2) strength- ens this suggestion. These authors find that the subcutaneous injection of adrenalin in proper dosage increases the “urea excreting activity of the rabbit’s kidney.” The observations of Marshall and Davis on cats were confirmed for rabbits by these investigators in that they found that “the removal of both suprarenal glands is followed by a depression of the urea excreting activity of the kidney, which is greater than that which follows similar operations in which the suprarenals are not re- moved.” Some time previous to the appearance of the work discussed above, Cow (3) published an article on the regulation of the functional 1 The data given in this series of papers were presented in abstract before the American Society for Pharmacology and Eperimental Therapeutics, New York, December, 1916. See Proceedings, Journ. Pharm. Exper. Therap., ix, 346, 1917, and before the same society in Baltimore, April, 1919. 302 RELATION OF RENAL NERVES TO RENAL FUNCTION 303 activity of the kidneys by means of the adrenals. He claimed both histologically and physiologically to have demonstrated a direct vascu- lar connection between the adrenals and the renal capsule in cats, by which adrenalin could be transported to the kidney directly without first passing through the general circulation. This caused a decrease in the secretion of urine, and hence the adrenals acted as inhibitors of renal secretion so far as the elimination of water was concerned. These different conceptions of the action of the adrenals on the kid- neys are not necessarily opposed to one another, for it might be con- ceived that they could act at the same time. That is, the products of adrenal secretion accelerate the elimination of urea, but inhibit that of water. In view of this it appeared interesting to us to test out the ef- fect of unilateral removal of the adrenal upon the kidney of that side. The results obtained indicated at once a definite effect. upon the se- cretion of the kidney on the operated side as compared with the kidney on the normal side. If the adrenals acted as inhibitors for water and accelerators for urea, and if such a control as Cow postulated were func- tioning, one would expect an increase in the excretion of water and a decrease in the excretion of urea. However, an increase in the excretion of both water and urea was noted on the operated side. It has been known for many years that section of the splanchnic nerve causes an increased flow of urine. Claude Bernard (4) showed that division of this nerve on one side in the dog increased the secretion of urine on that side. This has been confirmed by Eckhard (5), Knoll (6), Klecki (7), Vogt (8), Grek (9), Rhode and Ellinger (10), and Jungmann and Meyer (11), but is denied by Schwarz (12) and Peyrani (13) who claim a diminished secretion of urine for this procedure. Since adrenalectomy is always associated with unavoidable injury to the splanchnic which lies immediately behind the gland, the possibility of nerve injury as an explanation for the urinary findings after adre- nalectomy seemed very logical. To fortify this new point we chose also to section the nerves which surround the renal artery. This latter procedure does not interfere with the nerve supply of the adrenals and should demonstrate whether one can interpret the findings after adre- nalectomy as due wholly to injury to the nerve supply of the kidney. Another method used in connection with the search for a possible vascular relation between the adrenal and the kidney was the ligation of the adrenal vein at its junction with the vena cava. By this means it was hoped that the vascular connections which Cow describes as coursing from the gland to the capsule of the kidney would show some 304 E. K. MARSHALL, JR. AND A. C. KOLLS influence on the function of the kidney on the operated side, because after ligation of the main exit for the venous blood, the collateral circu- lation through these vessels would come more into evidence. METHODS Dogs were used in all the experiments. As the previous work had been carried out on cats, these animals were first used, but the difficul- ties encountered in collecting the urine separately from each kidney and in obtaining a sufficient amount for analytical procedures caused them to be discarded. Furthermore, it is probable that the dog’s kid- ney resembles the human more nearly than the cat’s. The various operative procedures, excision of the adrenal, section of the splanchnic nerve and section of the renal nerves, were done both immediately be- fore observations were made and also some days or weeks previous. In the latter case, the operations were performed aseptically under ether anesthesia. In the case of excision of the adrenal, the ventral route was chosen. The splanchnic nerve was sectioned just above the adrenal gland, the major splanchnic being always cut, while frequently other strands were also severed. In sectioning the renal nerves the following method was used. The peritoneum was incised and the renal artery and vein exposed. The artery was then freed of all visible nerve strands. This method does not completely denervate the kidney, but is probably freer of objection than painting the artery with phenol. Before making the observations on the secretion of the kidneys, the animals were anesthetized with paraldehyde, 1.7 cc. per kilo by stomach being given. Approximately 20 ec. of water per kilo were given with the paraldehyde. In some cases, where experiments were prolonged, it was found necessary to deepen the anesthesia and a saturated solu- tion of paraldehyde in 0.8 per cent saline was given intravenously. The animals were kept warm by means of an electric hot pad. This pro- cedure produced a very satisfactory anesthesia, and one in which the kidney was apparently but little affected. We were well aware of the danger in using anesthetics in studying renal secretion (14), but be- lieve paraldehyde is freer from objection than the commoner anes- thetics which are used. The secretion of urine was usually good even before a diuretic was administered, and the elimination of phenolsul- phonepthalein was the same as is shown by unanesthetized animals (15), (16). The ureters were exposed through incisions in the flanks and cannulated with small glass cannulae. All observations were made with the animals in the prone position. This method described by RELATION OF RENAL NERVES TO RENAL FUNCTION 305 Quinby and Fitz (17) is more satisfactory than exposing the ureters through the abdomen and making observations in the supine position. The urine was collected in small graduated cylinders over periods which were usually one hour in duration. The first period was usually one without administering any diuretic, although occasionally 0.8 per cent sodium chloride was injected to start the flow. At the beginning of the second period, diuresis was produced with 10 per cent sodium chloride intravenously which was given in doses of 2 to 4 ce. per kilo. In a few of the earlier experiments, 300 mgms. of diuretin were injected. In some of the experiments the third period consisted in injecting lac- tose (300 mgms. per kilo) and measuring the amounts eliminated. Phenolsulphonephthalein was given usually at the end of the experiment in the usual dose of 6 mgms. intravenously (15). The specimens were carefully measured, the specific gravity deter- mined with a small picnometer and analyses made for chlorides, urea and creatinine. Chlorides were determined by the method of McLean and Van Slyke (18), urea by the urease method described by one of us (19), and creatinine by Folin’s colorimetric method (20). Phenol- sulphonephthalein was determined with a Dubosq colorimeter. Lac- tose was estimated by the polariscope. At the conclusion of the experi- ment the kidneys were examined grossly and sections preserved in formaldehyde for histological study. In these experiments urea, cre- atinine and chlorides were determined in the urine at first because these substances had been previously examined by Marshall and Davis (1) in their work with cats. Later in the course of the investigations other urinary constituents were also determined. The chlorides figures are expressed for the sake of convenience as sodium chloride, although we are well aware that a portion of the chloride of the urine is present in combination with potassium. However, when diuresis was produced by hypertonic sodium chloride, the chlorides excreted were probably mainly in the form of sodium chloride. RESULTS Results of ligation of the adrenal vein. The following experiments in- dicate that ligation of the lumbar vein draining the adrenal has no ef- fect on the secretion of the kidney. If the mechanism postulated by Cow is correct and functions normally, we would expect more epinephrin to be discharged into the kidney on the operated side, and hence expect a smaller flow of urine from that side. In the following summaries of typical experiments under this heading and subsequent ones, the first 306 E. K. MARSHALL, JR. AND A. C. KOLLS column indicates the duration of the periods of collection, the R and L represent the urine from the right and left ureters respectively, and the various urinary constituents are expressed as percentages and also as the total amount in milligrams eliminated during the period. Experiment 1, Dog MK 8. Female, weight 9.9 kilos, February 9, 1916. On January 29, 1916, operation under ether ligating lumbar vein draining right adrenal, SPECIFIC TIME URINE | GRAV- UREA CREATININE SODIUM CHLORIDE ITY ce. ‘per cent| mgm. | percent | mgm. | percent | mom. 10.07-11.071| B | 4:5] 1-075] 3.40 | 153.0) 0.210} 9.4 | 0.04/ 1.8 pee L | 4.7 | 1.075} 3.39 | 159.3 | 0.182] 8.5 | 0.04] 1.9 io7-i2.07¢| EB | 23-2 | 1-032} 1.00 | 232.0 | 0.033 | 7.6 | 1.17 | 271.0 gel L | 24.6 | 1.031] 0.97 | 238.6 | 0.087] 9.1 | 1.17 | 286.0 12.07 1.07{| B | 17-0 | 1-040] 1.08 | 183.6 | 0.038 | 6.5 | 1.22 | 207.0 ann L | 19.5] 1.039} 1.03 | 200.8 | 0.040| 7.8 | 1.21 | 235.0 At 1.07, sulphonephthalein was injected and in the next hour the right eliminated 19.0 cc. with 38.5 per cent, and the left 18.5 cc. with 37.2 per cent of the amount injected. Experiment 2. DogMK9. Male, weight7 kilos, February 11, 1916. On Feb- ruary 5, 1916, lumbar vein draining left adrenal ligated. SPECIFIC TIME URINE | GRAV- UREA CREATININE SODIUM CHLORIDE ITY ‘ f 8 | 1.059} 3.64] 65.5 | 0.184 | 3.3 0.78| 14.0 1D. arene 4 11.056] 3.697) 88.6 | 0.177 4.2" | O.7aawA@ 19.3 | 1.022) 1.06 | 204.0] 0.025 | 4.8 1.47 | 283.0 20.0.) 1.020] 0.96 | 198.0 | 0.024] 4.8 | 1.45 | 290.0 ech osheaT \sal ten) 11.50-12.50 { At 12.50, sulphonephthalein was injected and the right secreted 40 per cent and the left, 42 per cent of the amount injected. Results of excision of the adrenal. The changes in the secretion of the kidney following removal of the adrenal on one side as compared to the secretion of the kidney on the opposite side may be summarized as fol- lows: The kidney on the operated side secretes more urine usually of a lower specific gravity and lower percentage of urea, constantly of a RELATION OF RENAL NERVES TO RENAL FUNCTION 307 lower percentage of creatinine and phthalein and an increased percen- tage of chlorides. The specific gravity and concentration of urea may be higher on the side with the most urine, as in experiments 3 and 5. During diuresis from injection of hypertonic sodium chloride, the dif- ference in the elimination of water by the two kidneys is augmented, and the specific gravity and percentage of urea, creatinine and phtha- lein are less on the side with the greater amount of fluid, while the chlorides are still generally increased in percentage. The total quanti- ties of chlorides are greatly augmented, of urea less, and of creatinine and phthalein approximately about the same or only slightly increased on the operated side. The one experiment in whith lactose was in- jected indicates that lactose resembles creatinine and phthalein. These changes are the same whether the observations are made immediately after removal of the adrenal or some weeks later. Experiment 3. Dog MK 14. Male, weight 10.5 kilos, March 17, 1916. Left adrenal removed one hour and a half before experiment was begun. SPECIFIC TIME URINE | GRAV- UREA CREATININE SODIUM CHLORIDE ITY, cc. per cent mgm. per cent mgm, per cent mgm. R | 1.8| 1.038} 1.68] 30.2] 0.271] 4.9 12.06-12.46 ( L | 2.2| 1.056, 3.60] 79.2| 0.228| 5.0 246. .4g {| B | 40| 1.052] 1.86] 74.4] 0.164] 6.5 | 0.48] 17.2 Tagen L | 22.0| 1.027] 1.06 | 233.2 | 0.031| 6.8 | 1.13 | 248.6 At 1.46 sulphonephthalein injected and in next hour, right eliminated 7.0 ce. containing 36.8 per cent, and left, 24.0 cc., containing 39.1 per cent of amount injected. Experiment 4. Dog MK 17. Male, weight 9.4 kilos, March 22, 1916. Left adrenal removed about one hour and a half before commencing experiment; 10 per cent saline given before first period. SPECIFIC TIME URINE | GRAV- UREA CREATININE SODIUM CHLORIDE ITY cc. per cent mgm. per cent mgm, per cent mgm. 1.00-1.45 R 6.5 | 1.025} 0.82 53.3 | 0.076 | 4.9 1.31 85.1 { ; L 32.5 | 1.020) 0.62 | 201.5 | 0.021 6.8 L.61 |.523.2 1.45-2 30 R 9.2 | 1.028) 1.26 | 115.9 | 0.078 Wee 1.65 | 151.8 Sia L DOA LeO2Z1 -OsSie 218k. BOO raed 1.77 | 477.9 At 2.30, sulphonephthalein injected and in next hour, right eliminated 15.5 cc. with 41.0 per cent, and left, 36.5 cc. with 44.3 per cent of amount injected. 308 E. K. MARSHALL, JR. AND A. C. KOLLS Experiment 6. Dog MK 15. Male, weight 13.5 kilos, March 25, 1916. Left adrenal removed March 18, 1916. SPECIFIC TIME URINE | GRAV- UREA CREATININE SODIUM CHLORIDE ITY cc per cent mgm. | per cent mgm per cent mgm, R 2.6 | 1.059} 2.04} 53.0] 0.326) 8.5 0.14 3.6 12,00-1,00 { L 5.2 | 1.057) 3.90 | 203.0 | 0.176 | ° 9:1 0.44 | 22.9 1.00-2.00 R 7.0 | 1.040} 2.29} 160.3] 0.111 | 7.8 0.87 | 60.9 i L | 20.5 | 1.026) 1.23 | 252.2 | 0.041 | 8.4 1.21 | 248.0 At 2.00, 4 grams lactose in about 20 cc. water injected intravenously. Inthenext hour, right eliminated 13.7 cc., containing 1.20 grams, and left, 23.0 cc., contain- In next hour, sulphonephthalein was excreted 44.3 per cent on the right, and 44.0 per cent on the left. Experiment 6. Dog MK 21. Male, weight 11.2 kilos, March 28, 1916. Right adrenal removed on November 5, 1915. ing 1.24 grams. SPECIFIC TIME URINE | GRAV- UREA CREATININE SODIUM CHLORIDE ITY cc per cent mgm. per cent mgm per cent mgm. 3004.00 R 10.1 | 1.045} 3.87 | 390.9 | 0.079 | 7.8 0.80 | 80.8 ; . L 3.9 | 1.054) 5.70 | 222.3 | 0.185 Tis?4 0.16 6.2 4.00-5.00 R 62.5 | 1.020} 0.99 | 618.8 | 0.012 Tet 1.43 | 893.8 5 j L 17.0 | 1.028} 2.17 | 368.9 | 0.040 | 6.8 1.33 | 226.1 At 5.00 sulphonephthalein injected, right excreted 33.0 cc. with 47.0 per cent, and left, 7.0 cc. with 41.0 per cent of amount injected. Results of section of the splanchnic. The changes after unilateral sec- tion of the splanchnic nerve are seen from the data in the following ex- ' periments to be identical with those following unilateral excision of the adrenal. The kidney on the side of the section eliminates more urine of a lower (or higher) specific gravity, and there is decreased (or in- creased) percentage of urea, decreased percentage of creatinine and phthalein, and increased percentage of chlorides. During sodium chlor- ide diuresis, the urine is greater in amount and always of a lower spe- cific gravity, there is a decreased percentage of urea, creatinine and phthalein, and an increased percentage of chlorides. The absolute amount of chlorides eliminated is greater on the operated side, of urea greater but in a less degree than chlorides, and of creatinine and phtha- lein only slightly greater or the same. The few experiments with lac- tose indicate that it resembles creatinine and phthalein in its excretion. RELATION OF RENAL NERVES TO RENAL FUNCTION Experiment 7. observations. 309 Dog MK 23. Female, weight 5.70 kilos, April 6, 1916. Left splanchnic nerve major and minor sectioned two hours before commencing TIME 12.22-1.25 { 1.25-2.25 { URINE SPECIFIC GRAV- ITY 1.050 1.037 1.021 1.015 UREA per cent 2.04 2.94 mgm. 40.8 135.2 219.6 231.2 1.22 0.68 SODIUM CHLORIDE CREATININE per cent mgm. 0.250 | 5.0 0.114 | 5.2 0.028 | 5.0 4.9 0.014 per cent 0.44 0.98 mgm, 8.8 45.0 235.8 452.2 1.31 1.33 At 2.25, sulphonephthalein was injected, and in the next hour, right eliminated 21.0 ce. with 38.5 per cent, and left, 58.0 cc. with 39.5 per cent of amount injected. Experiment 8. Dog MK 22. Male, weight 7.4 kilos, April 20, 1916. Left splanchnic sectioned April 1, 1916. SPECIFIC TIME URINE GRAVITY UREA ce, per cent mgm, R 1.7 | 1.034] 6.06 | 103.0 rai L Be2vy ies Bh -O8M ly: $1699 0 hh 228-7 fo 9.5 1.024) 2:26 | 214.7 ee PO ipa? 27.5) |y 1-016 | WALOO! |) 275-0 CREATININE per cent mgm 0.364 6.2 0.210 6.7 0.064 6.1 - 0.022 6.1 At 2.50, 2.2 grams lactose injected intravenously. During the next hour 1.05 grams in 13.8 ce. urine were eliminated by the right kidney, and 0.92 gram in 27.6 cc. urine by the left; 3.50-4.50, right eliminated 41.5 and left, 45.0 per cent of injected phenolsulphonephthalein. Experiment 9. Dog MK 32. Female, weight 8.0 kilos, July 18, 1916. Left splanchnic sectioned on May 19, 1916. : TIME 1.35-2.35 f 2.35-8.35 { 3.35-4.35 { Gi SiS a ed URINE SPECIFIC GRAV- ey: 1.055 1.053 UREA mgm. 63.6 60.5 126.5 153.3 115.9 140.4 CREATININE SODIUM CHLORIDE per cent| mgm. per cent mgm, 0.218} 4.5 0.214] 5.4 0.050 | 5.8 1.21 | 139.2 0.029 | 6.1 1. 270.3 0.042 5.8 Lue | V6LS5 0.029 | 6.2 1.287) 21680 310 E. K. MARSHALL, JR. AND A. C. KOLLS At 3.35, 2.4 grams lactose were given intravenously; in the period 3.35-4.35, 716 mgm. were eliminated by right kidney and 850 mgm. by the left. At 4.35, sulphonephthalein was injected and during the next hour, right eliminated 35 per cent, and left, 37 per cent of amount injected. Experiment 10. Dog MK 27. Male, weight 8.6 kilos, November 17, 1916. Left splanchnic sectioned and piece removed on April 26, 1916. TIME URINE UREA CREATININE SODIUM CHLORIDE cc. per cent mgm, per cent mgm, per cent mgm, 2.8 5.82 163.0 | 0.217 6.0 0.58 16.2 11.13-12.13 { 4.0/4) 04.471). 178.8 | <00143'|925.7 |\Polst | see R L P| 1028 2.62 283.0 | 0.058 6.3 L 6.1 12.13- 1.13 { | 23:0 | 1.48 | 340.4] 0.027 At 1.13, sulphonephthalein given and in next hour right eliminated 9.3 ec. with 33.0 per cent, and left, 27.5 ec. with 34.0 per cent of amount injected. Results of section of the renal nerves. The changes incident to section- ing the renal nerves on one side are, as far as can be judged, by the experiments carried out, identical with those of sectioning the splanch- nic or removing the adrenal gland. The following summaries of experi- ments indicate this. Experiment 11. Dog MK 33. Female, weight 7.0 kilos, June 7, 1916. Renal nerves on left side sectioned one-half hour before commencing observations. SPECIFIC , TIME URINE | GRAV- UREA CREATININE SODIUM CHLORIDE ITY 4 cc. per cent mgm. | per cent mgm. | per cent mgm. 11.45-12.45¢4| B | 3-25 1.053, 1.26 | 41.0 | 0.069 | 2.2 | Trace iS; 3.80 | 1.054) 1.20} 45.6 | 0.066 | 2.5 | Trace 12.45- 1.45 f| R 5/0)| 13048)) 474)" 73.5 | 0.067 |) 3.3 0.80 | 40.0 ; alt oi 8.0 | 1.041) 1.17} 99.5 | 0.040} 3.4 1035) sSieo At 1.45, 2.1 grams lactose injected intravenously. In next hour, right eliminated 4.3 ec. containing 670 mgm., and left, 8.0 ce. containing 736 mgm. At 2.45, sul- phonephthalein was injected, right eliminated 5.5 ec. with 47.6 per cent, and left, 12.2 ec. with 46.2 per cent of amount injected. a 11.15-12.45 1.45- 2.45 12.45- 1.45 { Ese = Gg Sie RELATION OF RENAL NERVES TO RENAL FUNCTION dll Experiment 12. Dog MK 34. Male, weight 4.8 kilos, June 13, 1916. Renal nerves on left side sectioned one hour before commencing observations. SPECIFIC URINE | GRAY- UREA CREATININE SODIUM CHLORIDE ITY cc, per cent mgm, per cent mgm per cent mgm. 2.35 | 1.079} 3.84] 90.2 | 0.167} 3.9 0.04 0.9 3.85 | 1.072} 3.09 | 119.0 | 0.108 | 4.2 0.18 6.9 oe2)) L.0sG) 2.22 | hoe | 0.043 | 2.2 1.40} 72.8 25.0 | 1.022} 0.74 | 185.0} 0.011 | 2.8 1.35 | 3387.5 5.8 0.72 | 41.8} 0.088} 2.2 1,26) | 73.1 26.0 0.47 | 122.2 | 0.009 | 2.3 1.39 | 361.4 In the third period, 1.44 grams of lactose were injected intravenously. At 2.45, sulphonephthalein was given, and in next hour right secreted 2.3 cc. containing ; 34.3 per cent, and left, 11.6 cc. containing 35.8 per cent of amount injected. , Experiment 13. Dog MK 35. Male, weight 6.2 kilos, June 19, 1916. Renal nerves on left side sectioned June 14, 1916. TIME 10.55-11.45 { 12.40— 1.40 { SPECIFIC URINE | GRAV- UREA CREATININE ITY cc. per cent mgm. | per cent mgm. 5.15) 1.0381} 1.95 | 100.4 | 0:115 | 5:9 11.00) 1.024) 2.01 | 221.1 | 0.053 | 5.8 8.3 1.67 | 188.6 25.5 0.59 | 150.5 SODIUM CHLORIDE per cent 0.86 1.01 mgm. 44.3 ies 1.21 1.45 100.4 369.8 Experiment 14. Dog MK 84. Male, 4.5 kilos, January 29, 1917. Left renal 11.45-12.45 { 12.45- 1.45 { nerves sectioned on January 3, 1917. URINE UREA CREATININE cc. per cent mgm. per cent mgm. R 10 3.69 36.9 0.160 1.60 L 1.8 3.49 Sie 0.091 1.65 R 2.0 hagAG) 30.2 0.095 1.90 L 4.5 1.438 64.5 0.042 1.90 SODIUM CHLORIDE per cent mgm, 0.34 6.8 0.62 27.9 At 1.45, sulphonephthalein was injected and in next hour, right eliminated 2.5 ce. with 29.3 per cent, and left, 6.2 cc. with 29.7 per cent of amount injected. 312 E. K. MARSHALL, JR. AND A. C. KOLLS DISCUSSION As stated above, the effect upon the secretion of the kidney after unilateral extirpation of the adrenal consists in the secretion of a greater volume of urine of lower specific gravity, a higher percentage and abso- lute amount of chlorides, a decreased percentage but greater absolute amount of urea, and a decreased percentage but approximately the same amounts of creatinine and phenolsulphonephthalein. We are not con- cerned here with the question as to whether the creatinine and sulphone- phthalein are secreted in exactly the same amounts by the two kid- neys. The figures indicate sometimes a slight increase, sometimes a slight decrease, and sometimes no change on the side with the greater flow. The important point is that no unmistakable and constant change occurs in the secretion of creatinine and phenolsulphonephthalein as is seen with water, urea and chlorides. These characteristic changes can be produced equally well by section of the splanchnic nerve or by section of the renal nerves. In fact, the effects of these three procedures cannot be distinguished from one an- other by examining the urines secreted by each kidney. In removing the adrenal gland, injury to the fibers of the splanchnic nerve is una- voidable. It would appear, therefore, unnecessary to postulate any - direct connection of the adrenal with the kidney of the same side to explain the phenomena observed; that these phenomena can be repro- duced by nerve sectioning where the nerve supply of the adrenal gland is undisturbed is shown by the experiments on cutting the renal nerves. The relation between the adrenals and the kidney as postulated by Cow (3) does not appear to function normally in the dog. This is further shown by the experiments on ligating the lumbar vein of one gland. No change in the urine on that side occurs. However, the in- ter-relations of the adrenals and kidneys as shown by Marshall and Davis (1) and signalized by a decreased functional capacity of the kidneys after the total ablation of the glands, and that indicated by Addis and his co-workers (2) by showing an effect of adrenalin on the urea excreting function of the kidneys are in no wise affected or invalidated by these experiments. In these cases, the effects can be produced through the general circulation, and not by local connections of the adrenal and kidney. Regarding the mechanism of the production of the changes in the secretion of the kidney after splanchnotomy, the usual explanation given is an effect on the blood flow through the kidney, although some RELATION OF RENAL NERVES TO RENAL FUNCTION 313 investigators are inclined to attribute it to a specific secretory effect of the nerve. In the following paper, we are inclined to believe that we have accumulated positive evidence that the first of these explanations is sufficient. The behavior of the different urinary constituents in relation to the different volumes of urine secreted by each kidney in these experiments is similar, in some respects, to that observed in similar experiments and also in experiments of a somewhat different nature. Knoll (6) examined the urine in dogs after cutting one splanchnic, and found the urine of the operated side of a lower specific gravity, lower percentage of solids and urea (determined by Liebig’s method), while the total elimination of solids and urea was greater. Grek (9) noted an increase in the abso- lute as well as percentage amount of chlorides after unilateral splanch- notomy in the dog. This was confirmed by Jungmann and Meyer (11). In a short preliminary note Rhode and Ellinger (10) state that after unilateral section of the splanchnic or renal nerves, the urine of the operated side contains a smaller percentage of solids (as determined by specific gravity and freezing point) but a greater absolute amount. The acidity to phenolphthalein was less, but the total amount of acid eliminated was greater. These changes were observed in animals sub- jected to operations weeks or months previously. No details are given in their preliminary note and the detailed communication promised has not come to our notice. The increased elimination of urine by the kidney on the operated side in these experiments can be considered in the nature of a diuresis as compared to the secretion of the organ of the normal side. Certain changes in the constituents of the urine are characteristic of diuretic urine in general. V. Schréeder (21), studying caffeine diuresis in the rabbit, found the total solids and nitrogen of the urine increased but not to the same extent as the water. Thompson (22) noted the same for nitrogen and urea during sodium chloride diuresis. Katsuyama (23) found caffeine diuresis in the rabbit accompanied by an increase in the alkali chlorides, but to a greater extent in the case of the sodium than the potassium. Later (24), he noted the same for urea and diuretin diureses. Loewi’s (25) studies on diuretics, mainly caffeine and sodium nitrate injected into dogs, indicated during diuresis an increase in the chlorides, urea (total nitrogen), sugar in hyperglycemia, and injected phosphates, but no change in the elimination of the sugar from phlor- hizin diabetes or the phosphates formed in metabolism. However, Bock (26) working with rabbits found that injection of solutions of 314 E. K. MARSHALL, JR. AND A. C. KOLLS glucose, sodium chloride and sodium sulphate, and purine derivatives produced a diuresis with increase of the phosphates, while a diuresis by the administration of water by mouth caused no increase in the phos- phate elimination. Baetzner (27), on the other hand, has failed to confirm Bock’s observations that water diuresis causes no increase in the elimination of phosphates in rabbits, but found a very marked in- crease. Rowntree and Geraghty (15) studied the influence of various diuretics on the elimination of phenolsulphonephthalein in cats. They came to the conclusion that under the conditions of our experiments it was found that those diuretics which are known to exert some stimulating influence on the activity of the secreting cells, or those diuretics in connection with which evidence is at hand indicating a stimu- lating action on the secreting cells (caffeine, urea, dextrose, phlorhizin, calomel), slightly increase the phthalein output, whereas those diuretics which act entirely by changes in osmotic tension or by changes in blood-pressure, etc. (hypertonic sodium chloride solution, potassium nitrate and digitalis), apparently have little or no effect on its excretion. To sum up, then concerning the effect of diuresis on the elimination of urinary constituents, the total solids, total nitrogen, urea and chlorides are increased while the phosphates are probably increased to a lesser extent. The percentage of chlorides may even rise in the diuretic ur- ine, while the other constituents are decreased in percentage at least during the height of the diuresis. The phenolsulphonephthalein excre- tion is not influenced by diuresis produced by sodium chloride. Cushny (28), in his recent monograph, calls particular attention to the differ- ence in behavior of substances during diuresis. According to him, all the substances of the urine are increased in amount during diuresis. The ‘‘no-threshold” substances—urea, phosphates, sulphates—are in- variably reduced in percentage but slightly increased in absolute amount, while the ‘‘threshold”’ substances—sodium chloride—are often reduced in percentage, but may actually rise in some circumstances. The changes which we have observed, therefore, are similar to those characteristic of an increased flow of urine, the percentage of chlorides rising while that of urea, creatinine and sulphonephthalein falls. The total amount of chlorides and urea is markedly increased, while the creatinine and phthalein are approximately unchanged. The behavior of creatinine in diuresis has not been studied, but it is known to be more or less independent of the volume of urine excreted.2. Similar changes * Our experiments reported in this paper would tend to show that creatinine may be independent of diuresis. However, they were not performed with this object. More careful experiments are being carried out on this point. a RELATION OF RENAL NERVES TO RENAL FUNCTION 315 in the behavior of various urinary constituents have been observed where the secretion of one kidney was lessened by opposing an obstruc- tion or resistance to the flow. It was shown that water and chloride decrease greatly in amount on the side with the lesser flow, while urea, phosphates, sulphates and indigo-carmine are much less decreased. Moreover, the last named constituents are present in higher percentage while the chloride may be present in higher percentage on the side with the smaller secretion (28). The behavior of creatinine and phthalein under these conditions has not been examined. The changes in the urine after section of the splanchnic, extirpation of the adrenal or section of the renal nerves appear to persist for months after the operation. This was also noted for the section of the splanch- nic and renal nerves by Rhode and Ellinger (10). On the other hand Quinby (29), in experiments on removing the dog’s kidney and re-im- planting it, found the changes in the urine of the operated side to dis- appear after a period of 10 to 14 days. In one experiment on the sec- tion of the renal nerves, observations made 20 days later indicated that the secretion of each kidney was identical, but this experiment is op- posed by many others, particularly on section of the splanchnic or re- moval of the adrenal. Further work is necessary to explain the appar- ent discrepancy with Quinby’s work, but it must be remembered that the procedures employed are not identical. The changes in the various constituents of the urine after these ex- perimental procedures, which are similar in many ways to the changes induced by other experimental methods of causing an increased or de- creased flow of urine from one kidney, and their bearing on the theories of urinary secretion, will be discussed in a subsequent communication. SUMMARY The changes produced in the secretion of one kidney by unilateral removal of the adrenal can be duplicated by sectioning the splanchnic nerve on one side, and also by section of the nerves on the renal artery and vein. It is not necessary to postulate any direct functional vas- cular connections between the adrenal and the kidney, as has been claimed by Cow, to explain these changes. Unilateral removal of the adrenal appears to affect the kidney of the same side only in so far as the nerves going to the kidney have been injured. This work, however, in no way invalidates the conclusion that complete removal of the adre- nals depresses the function of the kidneys. After the experimental procedures employed in this work,—unilateral removal of the adrenal, section of the splanchnic or section of the renal THE AMERICAN JOURNAL OF PHYSIOLOGY, VOL. 49, NO. 2 316 E. K. MARSHALL, JR. AND A. C. KOLLS nerves—the. kidney on the operated side secretes in general a more di- lute urine containing a greater percentage of chlorides but a smaller per- centage of urea, creatinine, lactose and phenolsulphonephthalein. This is always the feature during diuresis produced by sodium chloride, but during a normal flow the urea percentage may be higher on the side with the greater amount of urine. The total amount of water, chlorides and urea is greater on the operated side, while but little or no change is noticed in the total amount of creatinine and phthalein eliminated on the two sides. The similarity of these changes to those occurring during diuresis and in the lessened flow of urine produced by partial obstruc- tion of the ureter has been discussed. BIBLIOGRAPHY (1) MarsHALt AND Davis: Journ. Pharm. Exper. Therap., 1916, viii, 525. (2) Appts, BARNETT AND SHEvKy: This Journal, 1918, xlvi, 39. Appis, Foster AND BARNETT: This Journal, 1918, xlvi, 84. Appis, SHEVKY AND Brviser: This Journal, 1918, xlvi, 129. (3) Cow: Journ. Physiol., 1914, xlviii, 443. (4) Bernarp: Lecons sur les proprietes physiologique des liquides de l’organ- isme, 1859. (5) Ecxuarp: Beitr. z. Anat. u. Physiol., 1869, iv, 153. (6) Knouu: Beitr. z. Anat. u. Physiol., 1872, vi, 41. (7) Kuecxt: Arch. f. Exper. Path. u. Pharm., 1897, xxxix, 173. (8) Voat: Arch. f. Anat. u. Physiol., (Physiol. Abt.) 1898, 399. (9) Grex: Arch. f. Exper. Path. u. Pharm., 1912, Ixviii, 305. (10) Ruopr AND Evuincer: Zentralbl. f. Physiol., 1913, xxvii, 12. (11) JUNGMANN AND Meyer: Arch. f. Exper. Path. u. Pharm., 1913, 73, 49. (12) Scowanrz: Arch. f. Exper. Path. u. Pharm., 1900, xliii, 1. (13) Preyrant: Biol. Centralbl., 1881-2, i, 599. (14) See especially: Frey: Arch. f. d. gesammt. Physiol., 1907, exx, 66; Tompson: Arch. f. Anat. u. Physiol., (Physiol. Abt.), 1894, 117. (15) RownTREE AND GerAGuTy: Arch. Int. Med., 1912, ix, 284. (16) KerrH anD Putrorp: Arch. Int. Med., 1917, xx, 853. (17) QuinBy AND Fitz: Arch. Int. Med., 1915, xv, 303. (18) McLean anv Van Stryke: Journ. Biol. Chem., 1915, xxi, 361. (19) MarsuHa.u: Journ. Biol. Chem., 1913, xiv, 283. (20) Foxr1n: Journ. Biol. Chem., 1914, xvii, 469. (21) V. Scuroper: Arch. f. Exper. Path. u. Pharm., 1886, xxii, 39. (22) THompson: Journ. Physiol., 1900, xxv, 487. (23) Karsuyama: Zeitschr. f. Physiol. Chem., 1899, xxviii, 587. (24) Karsuyama: Zeitschr. f. Physiol. Chem., 1901, xxxii, 235. (25) Lorwr: Arch. f. Exper. Path. u. Pharm., 1902, Ixviii, 410. (26) Bock: Arch. f. Exper. Path. u. Pharm., 1908, lviii, 227. (27) Barrzner: Arch. f. Exper. Path. u. Pharm., 1918, Ixxii, 309. (28) Cusuny: The secretion of the urine, London, 1917, 88. (29) QuinBy: Journ. Exper. Med., 1916, xxiii, 535. STUDIES ON THE NERVOUS CONTROL OF THE KIDNEY IN RELATION TO DIURESIS AND URINARY SECRETION II, A CoMPpaARISON OF THE CHANGES CAUSED BY UNILATERAL SPLANCHNOTOMY WITH THOSE CAUSED BY UNILATERAL COMPRESSION OF THE RENAL ARTERY E. K. MARSHALL, JR. anp A. C. KOLLS From the Pharmcaological Laboratory, Johns Hopkins University Received for publication May 28, 1919 In the preceding paper, certain changes occurring in the urine after section of the splanchnic nerve on one side have been described. Many investigators are inclined to attribute any effects of the nerves upon the secretion of the kidney as due to vasomotor influences (1). The question, however, of true secretory action of the splanchnic or vagus upon the renal cells is an old one, but several recent investigations have been concerned with this problem. Asher and Pearce (2) claimed to have demonstrated secretory fibers in the vagus, but later Pearce and Carter (3) failed to confirm the earlier work, finding no change in the oxygen consumption of the kidney when secretory action was supposed to take place. Jungmann and Meyer (4) found an increase in the chlo- rides both in percentage and absolute amount following puncture of the floor of the fourth ventricle and that this was abolished after section of the splanchnic. Rhode and Ellinger (5) found that the changes after unilateral section of the renal nerves persisted for weeks or months after the operation. These changes they state to consist in the secre- tion of a larger volume of urine, of a lower percentage content in solids, and acidity to phenolphthalein, but a greater total amount of solids and acids. These last two investigators conclude that the splanchnic ex- erts a specific inhibitory-secretory action on the renal cells, which can- not be explained by vasomotor changes. Jost (6) has also advanced evidence that stimulation of the splanchnic can cause a diminution of the urine flow aside from the vasomotor effect. The evidence of these investigators, however, is not conclusive and does not appear to be gen- erally accepted (1). Numerous investigations have shown that an ani- mal can survive with a kidney which is completely deprived of its 317 318 E. K. MARSHALL, JR. AND A. C. KOLLS nerves, and Lohenhoffer and Quinby have shown that a transplanted or re-implanted kidney suffices for life and also shows a perfectly normal function (7). In the last year, Addis and his co-workers (8) have again advanced the idea of specific nervous control of the kidney to explain their results of the increase in the rate of urea excretion caused by adren- alin and the decrease caused by pituitrin. The changes, which we have described in the preceding paper of this series as resulting from the section of the splanchnic nerve, have been shown to resemble the change occurring in the urine in general when the secretion is markedly increased or decreased. The similarity to forms of diuresis and in partial ob- struction of the ureter has been pointed out by Cushny (9), and has been discussed in our previous communication. It would appear then on a priori grounds that a specific secretory action of the splanchnic nerve need not be invoked to explain these changes. The splanchnic nerve is known to contain the vasomotor fibers for the renal vessels, and its section would produce a vasodilatation in the kidney with a corresponding increased amount of blood flowing through the organ. In fact, Burton-Opitz (10) has demonstrated by the use of his ‘‘stromuhr”’ that stimulation of the splanchnic causes a diminished flow of blood through the kidney while section of the same nerve causes an increased blood flow through the organ. Moreover, the splanchnic nerve of each side supplies only the renal vessels of that side (11). Can the changes in the secretion of the kidney after section of the splanchnic be attributed entirely to the increased blood flow through the organ? The blood flow through the kidney can be conveniently diminished by partial constriction of the renal artery. A comparison of the changes produced by section of the splanchnic with those pro- duced by decreasing blood flow suggested itself as an aid in determining the cause of these changes. The changes following partial constriction of the renal artery in rabbits have been examined by Yagi and Kuroda (12). They found with diminished blood flow, after producing diuresis by injection of salines, a decreased amount of urine, chlorides, urea and sulphates. When a mixture of sodium chloride and sodium sulphate was injected as a diuretic, the reduction in chlorides was much greater than the fluid on the constricted side, that is, the percentage of chlorides was greater on the side of greater flow. When a mixture of urea and sodium chloride was used to produce diuresis, the water was more affected than chlorides. In both cases the urea was less affected than the water or chlorides, and the sulphates still less so. Thus, we see that the changes produced here are similar to those caused by section of the splanchnic RELATION OF RENAL NERVES TO RENAL FUNCTION 319 when the kidneys of the sides secreting the greater quantity of urine are compared. However, the elimination of creatinine or phenolsul- phonephthalein was not examined by these authors, their work was car- ried out on rabbits, and the secretion was only compared under the influence of a mixture of diuretics. Since our previous work on the sec- tion of the splanchnic had been carried out on dogs, and the changes in the elimination of chlorides, urea, creatinine and phenolsulphonephtha- lein extensively studied both during normal secretion and in diuresis produced by sodium chloride, we considered it important to re-investi- gate the effect of partial occlusion of the renal artery. Should it be possible to produce changes of an opposite nature to those obtained by sectioning the splanchnic by constriction of the renal artery, it would appear that increased blood flow through the kidney was sufficient to explain the changes brought about by section of the splanchnic. In other words, the changes might be the same from the two proce- dures when considered from the point of view of the secretion of differ- ent amounts of urine, in one case one kidney elimi- nating more urine by virtue of the splanchnic being sectioned and in the other the organ on the normal side Pressure Curr secreting more on Fig. 1 account of de- creased blood flow on the other side. If the changes occasioned by nerve section could be annulled by pressure on the artery, the value of the argument would be increased. The methods employed were those described in the previous commu- nication (13). The renal artery was exposed by an incision through the flank, and care was taken to disturb the nerves as little as possible, but the results show that some nerves were generally injured. We wished to adjust the pressure carefully so as to be able to study the effect of pressure on the renal artery after section of the splanchnic nerve on the same side. The apparatus used for exerting the pressure was a small rubber cuff, enclosed in an aluminium band. The cuff could be 320 E. K. MARSHALL, JR. AND A. C. KOLLS filled with water and pressure exerted by raising a column of mercury. This apparatus we have called the “pressure cuff.” It is illustrated in figure 1. A is a flattened tube of thin rubber dam which is covered with thin silk gauze or bolting silk and attached to a piece of rubber tubing. B is a small glass bottle, and C a thistle tube. A 1s filled with water and surrounded by the hinged aluminium band, then slipped about the artery and fastened by slipping the wire clasp D over the small projecting piece of metal, H. The tube connected to A is then passed through a small incision made conveniently near the kidney, and passed to the outside where B which has previously been filled with water and C are attached. C is then filled with mercury. Various degrees of pressure can be exerted on the renal artery by raising or lowering the mercury column by elevating C. RESULTS The first experiment described is one in which an attempt was made to neutralize the changes induced by section of the splanchnic nerve by diminishing the blood flow with pressure on the renal artery. The following summary presents the essential details and tabulated results. Experiment 1. Dog MK 81. Weight 7.1 kilos. December 22, 1916. Left splanchnic sectioned. Ureters cannulated. Left renal artery exposed through flank and ‘‘pressure cuff’’ placed around it. Diuresis produced by injection of 10 per cent sodium chloride. Urine collected for one-half hour periods without pressure on renal artery, then pressure adjusted so that each kidney secreted ap- proximately the same amounts of urine. At 4.38 pressure had been satisfactorily adjusted ; at 5.41 pressure was completely removed from left renal artery. TIME URINE UREA CREATININE SODIUM CHLORIDE cc. per cent mgm. per cent mgm, per cent| mgm. I | 3.25-3.55 : 13.0] 0.55 | 72.0) 0.012 | 1.60} 1.20 | 156.2 26.5 | 0.34] 90.1 | 0.006] 1.65 | 1.23 | 325.9 8.6 | 0.49 | 42.5] 0.017 | 1.50 1.18 | 101.3 3.55-~4,25 uy - { 30.5 | 0.28] 85.4| 0.004! 1.47] 1.29 | 398.5 i | 4.38-5.08 / 0.87 | 59.2 | 0.020} 1.47] 1.00] 67.5 aie 1.16 t 7.75| 0.67 | 51.9 | 0.017 | 1.35 90.0 Iv | 5.10-5.40 8.00] 0.88} 70.5 | 0.020| 1.63] 0.81] 65.0 11.00] 0.53 | 58.5 | 0.012| 1.38] 1.13 | 125.0 ae ie ey eb Sed jor) a .7| 0.75 | 42.7 | 0.026 | 1.52] 0.57] 32.5 2| 0.38) 76.5 | 0.007 | 1.57 | LOL \22a00 Vv | 5.43-6.13 ¢ \ RELATION OF RENAL NERVES TO RENAL FUNCTION 321 In the first two periods the urine from the operated side exhibits all the changes described as characteristic of splanchnic section. In the third period, the pres- sure adjusted has been just about enough to cause the two kidneys to secrete about equal amounts of urine, and the figures are not far from those obtained from an experiment on a normal animal. The correspondence to the normal is not ex- act but much better than one might expect when we realize that diminishing the blood flow by constricting the renal artery is not at all identical with nature’s method of increasing it by vasodilatation in the various branches of the renal artery. In period IV, the pressure is not as effective or has decreased and the correspondence with the normal is not as close. That the kidney has not been injured by this slight pressure on the artery is probable when we see in period V, where the pressure is removed, a quick return to the condition of periods I and II or at the commencement of the experiment. The following summaries are typical of other experiments in which the blood flow through the kidney was diminished by pressure on the renal artery. Experiment 2. Dog MK 98. Weight 7.80 kilos. February 5, 1917. ‘‘Pres- sure cuff” placed on left renal artery, and ureters cannulated. Diuresis produced by injection of 10 per cent sodium chloride and physiological saline. After opera- tion, animal was allowed to recover for about one hour, then collection of urine from each kidney commenced. At 1.18 pressure applied to left renal artery, and adjusted so that the left kidney was secreting about one-half as fast as the right. At 2.22 pressure lessened slightly. At 3.19 pressure removed. TIME URINE UREA CREATININE SODIUM CHLORIDE acy ce. per cent mgm. per cent mgm, per cent mgm. ( (ae | 3:0 1.67 | 50.2 | 0.033] 0.99 | 1.16 35.0 eee Vt | 8.0 || 1.51-\ 45.2 |°0-082 | 0.96 | 1244) vazea R| 12.1 0.87 | 106.2; | 0.011 |) Tes |) 1.411), 170.7 oo 1.18 ( Es Id./9 0.78 | 93.6 | 0.011} 1.25 |’ 1.45 }) 173.4 1.52-2.294| RB | 12.7 0.51 | 65.3 | 0.007) 0.99 | 1.56 | 200.7 ral ke a i 0.61) 44.8 | Ov012 |° 0:92 |) thoz 93.0 Bieta 4) ,| & |). 10-5 0.58 | 60.9 | 0.009] 1.02 | 1.24 | 130.8 eile! 60:9 0.65] 51.8 | 0.012} 0.99 | 1.34 | 106.2 Boz a7) | |, 6-8 | 0.55) 37.8 | 0.011) O75 | 2.12 | 77.7 TL} Ly} 6.2 O.57°| 35.7 (0. OR) trem aka 25 77.7 Experiment 8. Dog MK 102. Weight 7.80 kilos. February 13,1917. ‘‘Pres- sure cuff’’ placed on left renal artery, and ureters cannulated. At 1.37 slight pressure on left renal artery. At 2.40-3.30 pressure very much increased on left renal artery, and adjusted so that the right kidney was secreting about ten times 322 E. K. MARSHALL, JR. AND A. C. KOLLS as much as the left. At 4.08 pressure completely removed. At 11.23-12.00, in- travenous infusion of 50 ec. of a3 per cent sodium chloride, 3 per cent ureaand 0.3 per cent creatinine solution. At 3.37, infusion of 15 cc. more of above mixture. TIME URINE UREA CREATININE SODIUM CHLORIDE cc. per cent mgm. per cent mgm, per cent mgm. 11.4 1.28 145.3 | 0.162 | 18.5 0.93 106.7 14.0 1.07 150.8 | 0.127 | 17.8 0.94 132.0 17.8 0.84 150.1 | 0.092 | 16.4 1.08 193.7 15.3 0.86 131.9} 0.101 | 15.5 1.26 193.2 1.01 100.8 | 0.108 | 10.8 1.16 116.0 10.0 1.02 101.7 | 0.105 | 10.5 1.20 120.0 12.5 1.32 164.7 | 0.086 | 10.8 1.28 160.0 1.5 2.92 43.8 | 0.740; 11.1 1.73 26.0 iheie) 0.45 35.3 | 0.072 5.6 1.39 108.7 11.6 0.80 93.5 | 0.047 5.4 1.25 145.0 aS Pee es Sie S i=) & Experiment 4. Dog MK 99. Weight 6.4 kilos. February 7, 1917. At 11.15, ‘pressure cuff’’ placed on left renal artery. Ureters cannulated. Between 1.30 and 2.30, pressure adjusted on left artery. At 3.35 pressure considerably increased. At 4.10 pressure removed. TIME URINE UREA CREATININE SODIUM CHLORIDE =i cc. eae mgm. per cent mgm. per cent mgm, R 4.25 2.33 99.0} 0.047 | 2.01 1.80 76.5 12.20-12 .50 { L 5.70 1.80 102.6 | 0.035} 2.00 1.66 94.4 12.50- 1.20 R 8.0 0.81 64.4} 0.018 | 1.46 1.65 132.0 L 12.5 0.63 79.7 | 0.012 | 1.56 1.60 200.4 R 19.2 0.49 94.2} 0.008} 1.59 1.54 296.8 2.30— 3.00 { L 9.4 0.64 60.0 | 0.015] 1.38 1.57 148.0 3.05- 3.35 f R 18.5 0.50 93.0 | 0.008 | 1.51 1.55 287 .2 \| L 12.6 0.66 83.4 | 0.011 1.42 1.60 200.8 3 40- 4.10 f R |4.20-2 0.44 88.5 | 0.007 | 1.44 1.59 322.8 \ L 8.2 0.76 62.4] 0.016 | 1.34 1.48 122.0 55- 5.25 R 14.2 0.53 76.5 | 0.011 | 1.55 1.76 250.5 L 13.3 0.57 17207), O-OUG 147, 1.74 232.5 RELATION OF RENAL NERVES TO RENAL FUNCTION 323 DISCUSSION The changes caused in the secretion of the kidney by diminishing the blood flow by compression of the renal artery are exactly in the oppo- site direction to those caused by section of the splanchnic nerve. Water is diminished, chlorides are frequently diminished in percentage as well as absolute amount, while urea and creatinine are increased in percent- age but diminished in absolute amount. The creatinine is excreted in nearly the same quantities by the two kidneys, although in general the one with the diminished blood flows tends to excrete slightly less. It might be mentioned again that decreasing the blood flow by constricting the renal artery may not be exactly comparable to decreasing it by a mild vasoconstriction in the body, and moreover, we have found that if the blood flow is decreased to a great extent, all substances excreted fall markedly in absolute amount on the affected side. A certain blood flow is apparently necessary to furnish enough oxygen for nutrition of the renal cells. The following table which is collected from experiments reported in the preceding article and those given in this paper indicate the identity of the changes when the blood flow is decreased and when the splanchnic is sectioned. In the case of the experiments in which nerves are severed, Comparison of changes after section of splanchnic and after compression of renal artery PROCEDURE WATER eae UREA ewe ae C , er R TA 20146 | Oval MOK98 ompression on renal artery.......... L 100 | 100! 100! 100 Secti Pape Beet Yea R 100 | 100} 100; 100 | MK 32 ecmonsOfesplanchMiC.,.. 4.2.0: +1. L 132 | 200! 121 | 105 |- C ; Roce R 147 143n tat 105 | MK 99 ompression on renal artery......... ; L 100 | 100! 1001! 100 Secti nee ae {| R 100 | 100; 100} 100 | MK 32 echion.or splanchnic......2.2.....-. L 156| 171| 121! 107 C : seks {| R 250 | 2638) 148] 107 | MK 99 ompression on renal artery......... : L 100 | 100! 100! 100 R 100 | 100}; 100} 100 | MK 15 Removal of left adrenal.............. { L 293 | 407] 1571 107 324 E. K. MARSHALL, JR. AND A. C. KOLLS the secretion of the kidney of the normal side is represented as 100, and that of the other compared to this. In expressing the results of experi- ments on diminished blood flow, the secretion of the kidney with the lesser flow is taken as 100 and the one on the normal side compared to this. Data are selected not at random, but to obtain as close a corre- spondence as possible for it is our desire to show only that the changes characteristic of section of the splanchnic can be reproduced by a pro- cedure which affects the blood flow. It appears then that there is little doubt that the changes which have been described as characteristic of sectioning the splanchnic or renal nerves can be entirely reproduced by compressing the renal artery. This, of course, would cause a diminished pressure in the kidney as well as a diminished blood flow and smaller amount of oxygen to be utilized. However, increasing the blood flow would also cause an increased pressure and an increased amount of oxygen. Rich- ards and Plant (14), in their extremely important experiments on the perfusion of the kidney by a method free from the objections coincident to so many perfusion experiments, found that urine flow depended more on the rate of blood flow than blood pressure in the kidney. It is con- ceivable that the effects of increased and decreased blood flow depend entirely on the carrying of more or less oxygen to the kidney, but this is unlikely as long as the amount of oxygen is sufficient for the needs of the cells. Barcroft and Straub (15) found that blood flow might fre- quently change without any change in the oxygen consumption. It seems reasonable then to ascribe the effects of compression of the renal artery (provided it is not carried to too great an extreme, where decreased oxygen supply undoubtedly enters as a factor) to diminished blood flow. The changes, therefore, caused by sectioning the splanchnic or renal nerves can be explained by the increased blood flow known to occur under these conditions. The fact that the changes characteristic of splanchnotomy persist for weeks and months after the operation has been advanced as an argu- ment that mere vasodilatation cannot explain the changes. The vessels by this time would be supposed to have regained their tone. But as Bayliss (16) has pointed out during the observations, vasoconstrictor impulses, partly reflex, are being sent to the vessels of the kidney on the uninjured side, while they are absent on the side with sectioned nerves. Again, our experiments with nicotine would tend to support this as the differences in secretion of the two kidneys, even after the splanchnic has been sectioned for months, can be caused to disappear RELATION OF RENAL NERVES TO RENAL FUNCTION O20 after administration of nicotine. This is discussed more fully in a subsequent communication of this series. It appears, therefore, that the burden of proof still rests with those who would assign a specific secretory-inhibitory action to the splanchnic nerve aside from the changes which it causes by being the chief vasomo- tor nerve to the kidney. As long as the changes produced can be ex- plained entirely as vasomotor phenomena, it is unnecessary to invoke a specific secretory action for the nerve. SUMMARY The changes caused in the secretion of the kidneys after section of the splanchnic nerve on one side are in all respects examined similar to those caused by changes in blood flow through the kidney. The effect of section of the splanchnic is an increased flow through the kidney which is responsible for the changes in secretion. It appears unneces- sary at present to assign a specific secretory function to the nerve to explain these changes. BIBLIOGRAPHY (1) Cusuny: The secretion of the urine, London, 1917, 100. Bayuiss: Principles of general.physiology, London, 1915, 358. (2) ASHER AND Pearce: Zeitschr. f. Biol., 1914, Ixiii, 83. (3) Pearce AND Carter: This Journal, 1915, xxxvili, 350. (4) JUNGMANN AND Meyer: Arch. f. exper. Path. u. Pharm., 1913, Ixxiii, 49. (5) Ruopr AnD Eviincer: Zentralbl. f. Physiol., 1913, xxvii, 12. (6) Jost: Zeitschr. f. Biol., 1914, lxiv, 441. (7) For literature, see QuinBy: Journ. Exper. Med., 1916, xxiii, 535. (8) Appis, SHEVKY AND Brvinr: This Journal, 1918, xlvi, 129. (9) Cusuny: The secretion of the urine, London £1917, 102. (10) Burron-Opitz anp Lucas: Arch. f. d. gesammt. Physiol., 1909, exxvii, 143. (11) Burtron-Opitz aNp Lucas: Arch. f. d. gesammt. Physiol., 1908, exxv, 221. Burton-Opirz: This Journal, 1916, xl, 437. (12) Yacr anp Kuropa: Journ. Physiol., 1915, xlix, 162. (13) MarsHaLu AND Kouts: This Journal, 1919, xlix, 302. (14) Ricwarps AND Puant: Journ. Pharm. Exper. Therap., 1915, vii, 485. (15) Barcrort AND STRAUB: Journ. Physiol., 1910, xli, 145. (16) Bayruiss: Principles of general physiology, London, 1915, 358. STUDIES ON THE NERVOUS CONTROL OF THE KIDNEY IN RELATION TO DIURESIS AND URINARY SECRETION Ill. THe Errect or NICOTINE ON THE SECRETION OF THE TWO KIDNEYS AFTER UNILATERAL SECTION OF THE SPLANCHNIC NERVE E. K. MARSHALL, JR. anp A. C. KOLLS From the Pharmacological Laboratory, Johns Hopkins University, Baltimore Received for publication May 28, 1919 It is well known that nicotine, after a brief period of stimulation, causes a paralysis of sympathetic ganglia. It appeared probable that the injection of nicotine into an animal, in which unilateral section of the splanchnic had been performed, might amount to the section of the nerve on the other side. The effects, then, of unilateral splanchnotomy should be abolished by the injection of nicotine as far as the difference in the secretion of the two kidneys is concerned. The methods employed were similar to those described previously. Blood pressure, urine flow and kidney volume were recorded in some of the experiments. A modified type of the Roy oncometer was used. The following protocol (exper. 1) is illustrative of the general type of procedure employed. The effect of section of the splanchnic in pro- ducing a relative increase in the amount of urine on the operated side, as well as the effect of nicotine injected intravenously, of promptly causing the difference in fluid secretion of the two kidneys to disappear is clearly shown. Before section of the splanchnic nerve, the ratio of the amount of urine secreted by each kidney is nearly unity; after sec- tion of the nerve, the left kidney secretes about three times as much as the right; the intravenous injection of nicotine-causes the two kidneys to again return to the normal ratio and secrete the same amounts of urine. One of the most characteristic changes in the composition of the urine after section of the splanchnic nerve is a relative, as well as an absolute increase in chlorides. After nicotine this discrepancy in the amounts of chloride eliminated by the two kidneys disappears. Before section 326 RELATION OF RENAL NERVES TO RENAL FUNCTION _ 327 of the splanchnic (exper. 1), each kidney eliminated the same amount of chloride; after section, the left eliminated much the greater amount; the injection of nicotine caused each kidney again to eliminate equal quantities of chloride. Experiment 1. DogMK30. Male, weight 4.5 kilos. May 5, 1916. 1.15 p.m. Given 7.6 cc. of paraldehyde and 90 ce. water by stomach tube. 2.25-3.00 p.m. Operation through midline abdominal incision, carefully dis- secting free the left splanchnic, placing a loose ligature about it and passing this ligature through an incision in the flank. Animal placed on abdomen, and ureters cannulated. Saphenous vein cannulated for injection. 3.07 p.m. Injection of 9 ce. of 10 per cent sodium chloride. 3.20 p.m. Injection of 20 ec. of 3 per cent sodium chloride. 3.20-3.35 p.m. Urine, right 0.60 ec.; left 0.62 ce. 3.35-3.50 p.m. Urine, right 1.80 cc.; left 2.05 ec. 3.50-4.05 p.m. Urine, right 1.96 cc.; left 1.75 ec. 4.10 p.m. Left splanchnic cut; 4 ce. of 10 per cent sodium chloride injected. 4.12-4.27 p.m. Urine, right 0.65 cc.; left 1.89 cc. 4.27-4.42 p.m. Urine, right 0.55 ec.; left 1.69 ec. 4.42 p.m. Injection of 9 cc. of 10 per cent sodium chloride. 4.42-4.57 p.m. Urine, right 1.90 ec.; left 5.20 ce. 4.58 p.m. Twenty milligrams nicotine tartrate in 2 cc. water injected intra- venously. Anuria until 5.02. §.02-§.17 p.m. Urine, right 0.59 ec.; left 0.75 ec. §.17-§.32 p.m. Urine, right 1.51 ec.; left 1.59 ce. 5.23 p.m. Injection of 10 ec. 3 per cent sodium chloride. §.32-5.47 p.m. Urine, right 1.90 ec.; left 2.40 ce. 5.47-6.02 p.m. Urine, right, 1.77 cc.; left 2.63 cc. 6.02-6.17 p.m. Urine, right 2.8 ec.; left 4.40 ee. PERIOD 1 2 3 4 5 6 7 8 9 10 11 Left 21 19 56 82 33 | 38 wee | |) AS) || =| SS oo ee eee) Urine Right |. 60/1.80|1.96| = |0.65)0.55/1.90| & (0.59|1.51/1.90|1.77/2. 82 »--\) Left |0.62/2.05]1.75] & |0.89/1.69/5.20 $ |0.75]1.59/2. 40/2. 63/4. 40 ’ Left Ze ie Ratio, <:.. —— |1.03|1.14/0.90| % |2.91]3.07|2.74) © |1.27|1.05/1.26|1.48/1.56 Right = S S ‘5 . cq o Sodium = {/ Right | 13 [22/5] 1 | 30 |S] 35 | 32 s — The following protocols are condensed and the results expressed in the form of tables. Experiment 2 is a normal control animal in which urine volumes from each kidney were measured as well as the amounts 328 E. K. MARSHALL, JR. AND A. C. KOLLS of chloride eliminated. Nicotine was then injected exactly as in the operated animals and the effects noted. The data show that the amounts of urine excreted by each kidney, as well as the quantities of chloride eliminated in the time intervals employed are very nearly equal, and any differences that are encountered are negligible compared with the differences obtained by sectioning the splanchnic or the injection of nicotine. The injection of nicotine in the normal animal causes, as one would expect, no change in the ratio of the amounts of urine or sodium chloride eliminated by the two kidneys. Experiment 2. Dog MK 39. Female, weight 6.1 kilos. June 23, 1916. Nor- mal control. At various intervals during the experiment diuresis produced by injection of 10 per cent sodium chloride. Between periods 7 and 8, 20 mgm. nico- tine tartrate in 4 ec. water injected intravenously. Time of periods, 15 minutes each. | PERIOD te) 83 ay dat easel yee tal Ow 8 | 9 \-t0.1 1) a2 Urine, {| Right |0.79|0.901.95|3.30|1.7 |4.3 |3.7 2 0.76/1.25)3.50)3.50/3.55|1.20 Left 0.78)1.052.15)3.72)1.9 |4.3 |3.7 = |0.80|1.25/4. 20/3. 50/3. 30)0.80 | ne Left a Ratio. . Right 0.98|1.161.10)1.13)1.12/1.00/1.00)5|1.05/1.00|1.20/1.00/0.93/0. 67 8 Sodium 3 chlo- | Right | 13.8 50.0|26.0/70.0\60.0)'3|} 27.0 |51.0/50.0 ride, || Left 13.9 56.0/28.0/69.0/61.0/| 28.0 |59.0/47.0 mgm. | Experiment 3 shows the effect of nicotine on the relative increase of urine produced by removal of the adrenal gland on one side. It has been shown by the authors that this can be explained entirely by un- avoidable injury to the splanchnic fibers going to the kidney. The effect produced is the same as when the splanchnic is sectioned loans the adrenal. Experiment 4 shows that the action of nicotine takes place even if the adrenal (or splanchnic) has been removed some time previously. The adrenal was removed 4 months before the observations were made. Experiment 3. Dog MK 42. Male, weight 9.2 kilos. June 30, 1916. Left adrenal removed just before making observations. Diuresis produced at various intervals by injection of 10 per cent sodium chloride. Between periods 5 and 6, RELATION OF RENAL NERVES TO RENAL FUNCTION 329 27 mgm. nicotine tartrate injected; between periods 16 and 17, 18 mgm. nicotine tartrate injected. Length of each period, 15 minutes. Urine, eee, cule Sodium chloride, mgm...... { Experiment 4. Dog MK 19. Female, weight 10.7 kilos. PERIOD Right |0.40/0.65|0.50/1.25/0.95|2.80|2.10/3.75/3.55 Left |0.70/2.40/1.55 /4.20/3.50/3.25/1.60|2.55/2.80 Left ——— 11.75|3.70/3.10|3.36/3.70|1.16|0.76|0.68/0.79 Right Right 29.5 70.2 Left 13312 32.4 PERIOD 10 11 12 13 14 15 16 17 18 Right |3.96|2.35/2.52|1.50|1.46/1.25/1.50|1.15/1.60 Left |3.88/2.40/3.35|2.15/2.76/2.20/3.00]1.20/1.80 Left /0.98|1.02]1.33|1.43]1.91|1.80/2.00/1.04/1.13 Right ; Right Left 17.0 14.2 11.8 28.5 6.9 26.0 July 19, 1916. Left adrenal removed aseptically under ether anesthesia March 23, 1916. Dog al- lowed to recover. Diuresis produced at intervals during experiment by injection of 10 per cent sodium chloride. trate in 6 cc. water injected. Between periods 4 and 5, 30 mgm. nicotine tar- a3) & a _ 3° ~] oO 1 2 3 4 |.8] 5 6 7 8 9 ecal g = | E S Urine Right | 5.0] 2.1) 3.4 2.75 16.4] 9.7/12.6/12.4/15.5 Penh ASS SOLES 5 Left [20.210.2/17.9| 5.1) $]16.4/11.7|12..711.6/14.6 ° F Left S aeerrae ee ae a 4.04/4.86] 2.1/1.90].2/1.00/1.20/1.00/0.92/0.94 Right c 3300 E. K. MARSHALL, JR. AND A. C. KOLLS Blood pressure tracings were taken in practically all the experiments just before, during and after the administration of nicotine, as well as a graphic record of the flow of urine from each kidney. The blood pres- sure tracing was continued at intervals during the course of the experi- Wa catan’ Kantyvokt Ge Se: 1 257% AWA \ RY LLtibestllltth i} by K. ean ae mre oes Fig. 1 ment. Figure 1 shows graphically the influence of nicotine in causing the kidneys which have been secreting different amounts to approximate one another. The rise of pressure due to the general vasoconstriction in which the kidney participates causes a temporary anuria, but the rise only being very transient, the anuria quickly disappears. As noted RELATION OF RENAL NERVES TO RENAL FUNCTION 331 from the records of urine flow, the effect of nicotine on the secretion of the kidneys is very rapid, generally the two kidneys secrete the same number of drops of urine per unit of time a few minutes after the in- jection of nicotine. Sometimes, and in fact generally, it was noted that after the transient anuria from nicotine, the intact kidney (right) always commenced secreting slightly before the other. In some of the protocols which have been presented it is also noted that frequently after nicotine the intact kidney secretes slightly more than the other. Of course, one might argue that the function of this kidney was slightly greater than the other, a thing which is frequently noted in comparing the two kid- neys of a normal dog. But the phenomenon that after nicotine admin- istration the right kidney has a tendency to secrete somewhat more rapidly than the left occurs so regularly that it cannot be a coincidence. Although further experimental work appears necessary to decide the cause for this phenomenon, the following explanation may be advanced. Nicotine acts upon the vasomotor centers in the same way, as “ punc- ture diuresis.”” As the left kidney is almost entirely isolated from cen- tral nerve control, and the conducting mechanism from the center to the right kidney is intact, the effect is greater upon the right than the left and at this stage of nicotine action we have a greater flow from the kidney of the unoperated side. The “puncture diuresis” is generally admitted to be due to impulses emitted from the medulla oblongata passing to the kidney through the splanchnic nerves. These impulses may consist of either stimulation of the vasodilator center or depression of the vasoconstrictor, or a combination of both (1). In the course of the action of nicotine we have both stimulation and depression, so conditions would be favorable for this mode of action. After the rise of pressure from nicotine has subsided there is generally a slight fall which lasts for some time. This, however, did not regularly occur, even when the kidneys were secreting at an equal rate. Occa- sionally the pressure fell very rapidly after the rise due to the adminis- tration of nicotine until death occurred. The marked respiratory effect of nicotine was always noted, and occasionally respirations ceased and artificial respiration had to be resorted to for a short time. The toxic effects as noted on the different animals seem to depend a great deal on individual variation, some animals succumbing very shortly after the administration of a dose of nicotine far smaller than that which other animals received without any serious symptoms of a circulatory or respiratory effect being noted. THE AMERICAN JOURNAL OF PHYSIOLOGY, VOL. 49, NO. 2 332 E. K. MARSHALL, JR. AND A. C. KOLLS The most reasonable explanation of the effect of nicotine in causing the two kidneys to secrete practically equal amounts of urine after uni- lateral section of the splanchnic nerve is to be sought in its well-known paralytic action on all ganglia cells. The response of the kidney to splanchnic stimulation was tested be- fore and after the administration of nicotine by means of the oncometer. Several experiments of this type were carried out both with and without Teor ot 10 ¢m [ers* at gcm. proce faces } Fig. 2. Dog MK 44. Female, weight 4.5 kilos. Blood pressure tracing from the carotid. Left kidney freed carefully from the surrounding tissue and placed in oncometer. Left splanchnic carefully dissected out just above the adrenal, and placed in a shielded electrode. Splanchnic stimulated with induction coil for 5 seconds. After satisfactory normal records were obtained, 12.5 mgm. nico- tine tartrate in 2.5 ec. water were injected into the saphenous vein. Tracing A shows effect of stimulating splanchnic (coil at 10 cm. and 9 em.) before adminis- tration of nicotine. Tracing B indicates that practically no effect is obtained 20 minutes after administration of nicotine (coil 10 em. and 9 cm.). sectioning the nerve before stimulation. In all the experiments of this type, a definite contraction of the kidney volume was obtained with the stimulation before nicotine was given, but after the administration of the drug only a very slight or no response was obtained to the same stimulus. Figure 2 represents a typical tracing from one of these experiments. RELATION OF RENAL NERVES TO RENAL FUNCTION 333 We can conclude, therefore, that nicotine in the dosage given para- lyzes the ganglia of the fibers of the splanchnic nerve supplying the renal vessels. The dosage which has been employed to produce the effects described has varied between 2.8 mgm. and 4.4 mgm. per kilo of nicotine tartrate or 0.9 to 1.5 mgm. of nicotine; 0.2 mgm. per kilo was found to produce no effect, while 0.25 mgm. per kilo produced a transient effect for 5 minutes. The length of time which the paralysis of the renal ganglia has lasted has varied very widely with the same dosage in different animals. Thus, in experiment 1, the paralysis has begun to wear off after 30 min- utes with a dosage of nicotine of 1.5 mgm. per kilo, while in experiment 3, the paralysis lasts for one and one-half hours with a dosage of 1.0 mgm. of nicotone per kilo. In other experiments it was frequently found that with about this dosage of nicotine there was no apparent decrease in the paralysis after several hours. The length of time which the paralytic action of the drug on the renal ganglia continues depends apparently on the individual susceptibility of the animal, and resembles in this respect somewhat the toxic action of nicotine. The fact that nicotine exerts the same action on an animal in which the splanchnic nerve has been sectioned some months previously strengthens the suggestion made in the second communication of this series to account for the fact that the changes characteristic of unilat- eral splanchnotomy persist for months. Although the vessels of the kidneys on the operated side may have regained their tone by this time, during the observations vasoconstrictor impulses are being transmitted to the normal kidney, while the organ on the side with the sectioned nerve is free of them. Nicotine not only abolishes these impulses but also paralyzes the ganglia on both sides. A few experiments, not in- cluded here, have shown that after section of the renal nerves on one side, nicotine will neutralize the effects of this. This confirms in a physiological way the conclusions of Renner (2), on histological grounds, that ganglia cells exist as far as the renal hilus. SUMMARY The marked difference in the amounts of urine secreted by the two kidneys after unilateral section of the splanchnic nerve is caused to disappear by the administration of nicotine intravenously in dosage of 1 to 1.5 mgm. per kilo. The relative and absolute increase of chlorides characteristic of splanchnic section is also abolished by this procedure. 304 E. K. MARSHALL, JR. AND A. C. KOLLS This effect of nicotine occurs whether the nerve is sectioned just before the observations or some months previously. The cause is to be found in the paralysis of the sympathetic ganglia cells by nicotine. BIBLIOGRAPHY (1) Cusuny: The secretion of the urine, London, 1917, 103. (2) Renner: Deutsch. Arch. f. klin. Med., 1913, ex, 101. STUDIES ON THE NERVOUS CONTROL OF THE KIDNEY IN RELATION TO DIURESIS AND URINARY SECRETION IV. UNILATERAL LIGATION OF ONE BRANCH OF ONE RENAL ARTERY AND UNILATERAL SPLANCHNOTOMY E. K. MARSHALL, JR. ann A. C. KOLLS From the Pharmacological Laboratory, Johns Hopkins University, Baltimore Received for publication May 28, 1919 In the first two communications of this series, it was shown that cer- tain changes in the elimination of water, chloride, urea, creatinine and phenolsulphonephthalein were characteristic of the section of the splanchnic. It was further shown that these changes could be explained entirely as due to an increased blood flow through the kidney. In these experiments one kidney was compared with the other, the two organs being subject to the same extra-renal influences—changes of blood pres- sure, changes of blood composition, the influence of the anesthetic, if any, etc. Any differences in the secretion of the two kidneys can, therefore, safely be ascribed to a difference in blood flow. We can say, then, that the secretion of water and chlorides is very markedly affected by changes of blood flow, the secretion of urea is definitely affected but to a less extent than water or chlorides, while the secretion of creatinine and phenolsulphonephthalein is very little if at all affected by this procedure. It is well known that the creatinine output in any given individual on a constant diet is quite constant from day to day and does not vary with the volume of urine. Phenolsulphonephthalein has also been shown to be more or less independent of the volume of urine (1). In fact, the originators of this test of renal function state that phthalein is eliminated in a different way from salt and water. It is possible to reduce the amount of active renal tissue by ligating one branch of the renal artery (2). Of course, in the reduction of the amount of renal tissue by this method, the blood supply is also reduced, - that is, the portion of a kidney has per unit of weight the same blood supply as the original kidney. However, it occurred to us as possible to increase the blood supply of the portion of a kidney to something like the blood supply of the original kidney by sectioning the splanchnic nerve as well as ligating the posterior branch of the renal artery. Here, 335 336 E. K. MARSHALL, JR. AND A. C. KOLLS then, we would have a kidney about one-half the size of the normal one but with a blood supply increased and probably somewhat approximat- ing that of the normal kidney. It appeared interesting to examine the elimination of substances under these conditions compared to their elimination by the intact kidney on the other side. The methods adopted were exactly similar to those described in the preceding papers. The posterior branch of the renal artery was ex- posed by a midline incision through the abdomen, and ligated. The splanchnic was sectioned at the same time just above the adrenal gland. The following summaries are typical of the experiments. Experiment 1. Posterior branch of left renal artery tied. Dog MK49. Male. Weight 5.3 kilos. At 10.15 posterior branch of left renal artery ligated; 10.30 ureters cannulated. At 11.30 intravenous injection of 50 ec., 0.8 per cent saline. At 12.30, 10 cc. of 10 per cent sodium chloride given intravenously. At 1.30, 1.6 grams lactose given intravenously. TIME URINE UREA CREATININE Soorat CHLORIDE cc. mgm. mgm mgm R 2.75 88.3 4.2 11.00-12.30 { L 1.65 50.5 aM R 19.5 165.8 2.9 197.0 12.30- 1.30 { it 10.6 76.4 1.5 111.2 1.30. 9/30 R 24.5 164.2 3.9 235.2 i 14.0 78.4 2 145.6 At 2.30, 6 mgm. of phenolsulphonephthalein were injected intravenously. In the next hour the right kidney secreted 18.0 ce. urine containing 41.5 per cent, and the left, 9.3 cc. urine containing 21.2 per cent of the injected dye. Experiment 2. Posterior branch of left renal artery ligated; left splanchnic sectioned. Dog MK 114. Weight 9.9 kilos. March 14, 1917. Left splanchnic sectioned just above the adrenal gland. Posterior branch of left renal artery ligated. Ureters cannulated. At 11.55 given 15 cc. of 10 per cent sodium chloride solution. TIME URINE UREA CREATININE Gaerne ce. mgm. mgm, mgm. f R 13-1 321.0 8.00 215.0 12.00-2.00 \ i, 12.2 194.5 4.35 187.5 2.00-4.00 { R 13.8 385.5 7.15 : 3 L 10.2 214.5 4.00 RELATION OF RENAL NERVES TO RENAL FUNCTION 337 Experiment 3. Posterior branch of left renal artery ligated; left splanchnic sectioned. Dog MK 115. Weight 10.1 kilos. April 5, 1917. Left splanchnic sectioned just above adrenal gland. Posterior branch of left renal artery ligated. Ureters cannulated. At 12.10, 12.35, 1.05 and 2.35, 10 cc. of 10 per cent sodium chloride solution injected. SODIUM TIME URINE UREA CREATININE CHLORIDE ce, i Se AR ha mgm, mgm, : R 17.0 180.0 10.08 102.4 a aa { L 20.8 156.9 5.96 196.6 R 24.9 351.0 12.24 414.0 lle Rad { i 30.1 264.8 6.50 497.4 Experiment 4. Posterior branch of right renal artery ligated; right splanch- nic sectioned. Dog MK 100. Weight 6.10 kilos. February 9, 1917. At 10.20 posterior branch of right renal artery ligated. At 11.45 right splanchnic nerve sectioned in thorax just above the diaphragm. Ureters cannulated. At 1.05, 12 cc. of 10 per cent sodium chloride solution were injected. At 2.05, 1 ee, (6 mgm.) of phenolsulphonephthalein given intravenously. TIME URINE UREA CREATININE Sees CHLORIDE cc. mgm. mgm mgm R 4.8 31.5 1.50 12.05-1.05 { L 50 52.2 3.00 R 19.5 46.8 1.28 200.0 ieyre 05 { L 17.4 100.2 2.64 184.0 During the next hour, 6.4 cc. of urine were secreted by the right kidney con- taining 16 per cent of the injected phthalein, while 2.6 cc. were obtained from the left, with 34.5 per cent. It is seen that ligation of the posterior branch of one renal artery in the dog is followed by a reduction of the water, urea, chlorides, creatin- ine and phenolsulphonephthalein to about one-half of that eliminated by the other kidney (exper. 1). However, if the blood supply of the portion of a kidney is increased by section of the splanchnic, water and chlorides are eliminated equally well or in fact sometimes in greater amount than by the entire kidney with a normal (or less than other) blood flow. The creatinine and sulphonephthalein are not appreciably increased by the increased blood flow, while the elimination of urea may be increased considerably but not to the marked extent of water 338 E. K. MARSHALL, JR. AND A. C. KOLLS and chlorides, it still remaining less than the amount eliminated by the normal kidney. These results are exactly what would be expected by our previous work on the effects of blood flow. They serve, however, to clearly em- phasize that when two kidneys are dividing the work of renal excretion between them and the extra-renal factors are the same for both, the relative amounts of water and chlorides which will be eliminated by each depends more upon the blood flow than the size of the kidney, while the relative secretion of creatinine and phenolsulphonephthalein depends mainly on the amount of active renal tissue and to a much less © if any extent upon a blood flow within certain limits. If the blood flow is very much decreased, creatinine and substances resembling it are markedly affected, but here other factors (e.g., insufficient oxygen) are brought into play. Richards and Plant (8) found in the perfused kidney that a certain minimum blood flow was necessary for any secre- tion of urine. SUMMARY When the posterior branch of one renal artery is ligated, and the secretion of such a kidney compared to the other, it is found that roughly about one-half as much water, chlorides, urea, creatinine and phenolsulphonephthalein are eliminated. When the blood flow of such a kidney is increased by section of the splanchnic, the portion of a kid- ney may eliminate more water and chlorides than the other intact kid- ney, while creatinine and phenolsulphonephthalein will still be reduced about as much as before. Urea stands in an intermediate position. BIBLIOGRAPHY (1) RowntrREE AND Geracuty: Arch. Int. Med., 1912, ix, 284. (2) Bropew: Johns Hopkins Hosp. Bull., 1901, xu, 10. MacNiper: Journ. Med. Res., 1911, xxiv, 425. (3) Ricuarps AND PLant: Journ. Pharm. Exper. Therap., 1915, vii, 485. STUDIES ON THE NERVOUS CONTROL OF THE KIDNEY IN RELATION TO DIURESIS AND URINARY SECRETION V. CHLORIDE AND SULPHATE DIURESIS AFTER UNILATERAL SPLANCHNOTOMY E. K. MARSHALL, JR. anp A. C. KOLLS From the Department of Pharmacology, Johns Hopkins University, Baltimore Received for publication May 28, 1919 During the course of the investigation which has been described in the preceding papers, an attempt was made to measure the relative elimination of sulphates by the two kidneys after unilateral section of the splanchnic. In order to obtain a larger amount of sulphates for determination, diuresis was produced by an intravenous injection of sodium sulphate instead of the sodium chloride solution usually em- ployed. It was found that the difference in urine secretion by the two kidneys tended to disappear during sulphate diuresis instead of being magnified as it was during chloride diuresis. That sodium sulphate and sodium chloride act in a different manner in producing diuresis is well known. It is also recognized that in the sulphate diuresis changes must occur in the kidney itself, while in chlo- ride diuresis changes in the blood are probably mainly responsible (1). The difference between sulphate and chloride in producing diuresis is well shown by the experiments of Barcroft and Straub (2), in which they found that sulphate diuresis was accompanied by an increase in the oxygen consumption of the kidney and that chloride was not. Also, Knowlton (3) found that the addition of gelatine to a hypertonic sodium chloride solution diminished diuresis when it was injected intra- venously, while under the same conditions gelatine had little effect upon sodium sulphate diuresis. The experiments which we have carried out are reported because they furnish another method of demonstrating the difference between chlo- ride and sulphate in producing diuresis. The methods used were those already described as employed in these investigations. The following experiments which are shown graphi- 339 340 E. K. MARSHALL, JR. AND A. C. KOLLS cally in the accompanying charts are selected from a number which have been performed. Experiment 1. Dog M6. Male, weight 9.2 kilos. Anesthetized with paralde- hyde. Left splanchnic sectioned and ureters cannulated. Urine collected from each kidney in 15 minute periods. At points indicated, 20 cc. of 10 per cent so- dium chloride and 15 ee. of 10 per cent sodium sulphate solutions given intrave- nously. The results are shown in figure 1. Experiment 2. DogM1. Male, weight 8.0 kilos. Anesthetized with paralde- hyde. Left splanchnic sectioned and ureters cannulated. Urine collected from each kidney for 10 minute periods. At points indicated, 10 cc. of 10 per cent sodium chloride, and 5 ce. of 10 per cent sodium sulphate injected intravenously. (Fig. 2.) Since it has been previously shown that the changes after section of the splanchnic nerve can be explained by the increased blood flow through the kidney, experiments were carried out to determine if the difference between sulphate and chloride diuresis could be demonstrated under conditions where blood flow was decreased in one kidney. Cushny (4) found that when pressure was exerted on one renal artery of a rabbit so as to keep the volume of that kidney constant (as measured by the oncometer), injection of 3 per cent sodium chloride caused a marked diuresis in the normal kidney but none in the one with compressed ar- tery. He interpreted this as proving that saline diuresis was due to changes in the circulation of the kidney, but has recently stated that the experiment proves nothing. The fact that the oncometer does not measure blood flow during diuresis and that the pressure in the renal artery and capillaries was reduced, invalidates the conclusions drawn (5). The changes following the reduction of diuresis by compression of the renal artery in rabbits were studied by Yagi and Kuroda (6). They used, however, mixtures of sodium chloride and sodium sulphate or sodium chloride and urea to produce diuresis. With the amount of pressure and the mixtures of diuretics used, there was always a marked difference in the amounts of urine from the two kidneys. The ‘‘pressure cuff”’ previously described (7) was used for compress- ing the renal artery on one side. In accordance with our expectations from the results obtained with sulphate and chloride injections after increasing the blood flow of one kidney by sectioning the splanchnic nerve, the limitation of diuresis is much greater with chloride diuresis than sulphate by compressing the renal artery. The following experi- ment is typical of several performed in this way. Urine RELATION OF RENAL NERVES TO RENAL FUNCTION 341 ° 3 = ec. Urine Lal hl cl ae ! Mz2 PZAaagaggggZy Sodium chloride and Sodium Sulphate Diuresis Doq M6 ha}t Splenchnie Sedlioned ZZ urine from Right wdney “Periods = 15 minutes. HD Urine Yrom Leje Kidney — Kalio so Fig. 1 MD LA Sey, ‘“aUugys AG4Z Sodium chloride and Sodium sulphate Diuresis Deg M}. Lett Splonchnic Sectionea. Urine trom Right Kidney (&. Urine trom Leyt Kidney o—= Ratio of bett /Right. Fig. 2 Periods = 15 minutes, 342 E. K. MARSHALL, JR. AND A. C. KOLLS Experiment 3. Dog MK 116. Female, weight 5.5 kilos. Anesthetized with paraldehyde. Compression on left renal artery. Urine collected from each kid- ney in half-hour periods. At point indicated, 20 cc. of 10 per cent sodium sul- phate and 20 ce. of 10 per cent sodium chloride injected intravenously. (Fig. 3.) As possible explanations of the differences observed with sulphate and chloride in producing diuresis after sectioning one splanchnic, a paralysis of some portion of the sympathetic nerve elements as produced by nicotine (8), or a more or less maximal dilatation of the vessels of Natl Wee = 44 ° 4 ai Ey Ratio KIS WN .’ QR WS Oy aN IQA Sodium chloride and Sodium sulphate Dinresis Deg MK Ib Compression of Left Renal Artery. Urine {trom Right Kidney urine Yrom Left Kidney <—+ Ratio of Right t/tatt Fig. 3 each kidney by the injected sulphate might at first suggest themselves. That neither of these explanations is correct is shown by the experi- ments contrasting sulphate and chloride diuresis after careful compres- sion of one renal artery. Moreover, neither of the above actions is known to be attributed to the sulphates. As stated before, however, there is a great deal of evidence showing that sulphates and chlorides behave very differently in excretion, and act in a different manner in producing diuresis. Whatever explanation finally explains the differ- a E aaa RELATION OF RENAL NERVES TO RENAL FUNCTION 343 ences in action of sulphate and chloride in producing diuresis will ex- plain our findings. That the sulphate diuresis occurs mainly from changes in the kidney itself as first suggested by Magnus (9), appears reasonable from the data at hand, but whether a stimulation of the renal cells or inhibition of re-absorption in the tubules is considered respon- sible depends on the theory of urine secretion that is accepted. SUMMARY After section of the splanchnic nerve on one side, sodium chloride produces a greater diuresis on the operated side than the normal one. Sodium sulphate, on the other hand, produces an almost equally good diuresis from each side. Compression of one renal artery limits the diuresis from sodium chloride much more than it does from sodium sulphate. BIBLIOGRAPHY (1) Cusuny: The secretion of the urine, London, 1917, 146. (2) BarcrortT AND Straus: Journ. Physiol., 1910, xli, 145. (3) Knowtron: Journ. Physiol., 1911, xliii, 219. (4) Cusuny: Journ. Physiol., 1902, xxviii, 431. (5) Cusuny: The secretion of the urine, London, 1917, 125. (6) Yact anp Kuropa: Journ. Physiol., 1915, xlix, 162. (7) MarsHaut AND Kouts: This Journal, 1919, xlix, 323. (8) MarsHaLu AND Kouts: This Journal, 1919, xlix, 326. (9) Magnus: Arch. f. Exper. Path. u. Pharm., 1900, xliv, 396. As ¢ ae id> gtk? ¢ ; *- ’ ras Trey tent iteu haa | : a r. . fy? AAS —s s Ry a ‘ 7 ] TOI baal t ier Larios 7 Piri ‘ ile > * a bee Beetalrs } r fol 4 Dy ‘shh x an : 7 ae | p Ageaboris si ite. Sob ovat oifthuetl apd alah att marl Wi dha , att tte One Fal UEP auY no eb iege vi F; , ¥4t4 . uMTtOSE te ik ale hal iO} RT ‘i> =e at sodle oaf 2.4 athyiva ort ane hie oes pe (igi minke iow u A y ‘ ott = es - - sa ® é ap , eae * > bua, +50 reiyanon adt Soe \ % aol evi on ein . ‘x FO 14%, quot {eee at Oe). jolavdt virtual LAT 7-9) Ue Pa yo siFsg Tt: al} : D Ptaae oh ri rea a RAT | sii) tatinel Guage CF av yintes Ss taurdt Hd pre aa ae. THE AMERICAN JOURNAL OF PITYSIOLOGY VOL. 49 AUGUST “I, 1919 No. 3 STUDIES IN SECONDARY TRAUMATIC SHOCK III. CrrcuLatory FamtureE Duvet To ADRENALIN JOSEPH ERLANGER anp HERBERT S. GASSER From the Physiological Laboratory of Washington University, St. Louis Received for publication May 22, 1919 Early in 1917 the English Medical Research Committee, reporting for Bainbridge and Trevan (1), announced that shock can be produced in animals by the continuous injection of adrenalin for 20 minutes or more, at such arate as to keep the arterial pressure up to that attained by moderate stimulation of sensory nerves. They found that during the injection the arterial pressure rose to a high level, that the systemic venous pressure either was not altered or fell, and that the portal pres- sure rose and remained at a high level, indicating an obstruction to the flow of blood through the liver. In the course of our investigation of shock we have repeated certain phases of the experiments of Bainbridge and Trevan and as a result have gained considerable information bear- ing upon the so-called shock-producing action of adrenalin, and upon the action of massive doses of adrenalin in general. In the course of this investigation information was desired with re- gard to the effect of interposing a high resistance to the passage of the blood through the liver at the point where the normal peripheral re- sistance of this organ presumably resides. This led to a study of the effect upon the circulation of injecting into the portal vein toward the liver a suspension of lycopodium spores. This series of experiments forms the basis of the second part of this paper. 345 THE AMERICAN JOURNAL OF PHYSIOLOGY, VOL. 49, NO. 3 346 JOSEPH ERLANGER AND HERBERT S. GASSER THE CIRCULATION AFTER THE CONTINUOUS INJECTION OF MASSIVE DOSES OF ADRENALIN Methods The adrenalin, usually consisting of from 6 to 11 cc. of the 1: 1000 solution freshly obtained from Parke, Davis and Company, was in- jected, usually into the femoral vein, in the course of 21 to 29 minutes, an aliquot part entering the circulation rapidly at the beginning of each half-minute. After the first two or three injections the arterial pressure no longer falls in the intervals;—the effect becomes continuous. In a few experiments the injection was made into a mesenteric vein. We were unable to distinguish any clear difference in the response of the organism to the administration of the adrenalin by these different paths. A record was made of the pressure in the carotid artery, and the peripheral resistance was measured by the inflow method (2), (3). In some of the experiments readings of the jugular and portal venous pressures were also made from time to time, by the method previously described. It must be borne in mind in connection with these experi- ments that the inflow method gives but faint clue to the action of the vasomotor center as long as the adrenalin is exerting its effects peripher- ally. Dogs alone were used; they were anesthetized with ether. The criteria of shock herein employed have been those described in the first paper of this series (3). Results The action of these doses of adrenalin has been so variable that a clear conception of it can be conveyed only by describing and discussing a number of the experiments. An attempt at generalization before such a detailed treatment would surely fail to carry conviction. Experiment 41 (fig. 1). The first injection, lasting 21 minutes, consisted of about 6 cc. of 1: 1000 adrenalin. It raised the arterial pressure from 120 mm. Hg. and held it at about 168 mm. Hg. With the termination of the injection the arterial pressure fell abruptly to 74 mm. Hg., and then to 62, before it recovered slowly to 92 mm. Hg. The inflow rate (femoral area) was not followed during the injection period, but immediately thereafter it was almost nil. It quickly increased, however, to at- tain more than twice its initial rate within 5 minutes, and then decreased some- what more deliberately, finally becoming constant at about half the initial rate. It would seem, therefore, that the adrenalin at first practically stops the blood flow in the femoral area, but that, with the termination of the injection, there develops, almost immediately, a tremendous dilatation. When this has passed CIRCULATORY FAILURE DUE TO ADRENALIN 347 off and the peripheral action of the adrenalin presumably has come to an end, the center seems to be normally active; indeed it is more than normally active, pre- sumably under the stimulus of an abnormally low arterial pressure. A second injection of 6 cc. adrenalin in the course of 20 minutes raised the arterial pressure to 164 mm. Hg. and caused the heart to become very irregular, c. With the completion of the injection the arterial pressure declined somewhat more slowly than after the first injection, but it finally got as low as 40 mm. Hg. The heart here, d, seemed to be failing; but about 20 minutes later, at e, the heart’s action improved and the arterial pressure began to rise. J =x = cc. = 2.0 200 e? ' 1.5 150 ’ ; 5 ' e ; 1.0 100 : i} | ! ‘ 0S 50 gle ei 8 ‘ ' e Hr 2:20 “3100 4-00 5:00 Fig. 1. Experiment 41. Effect of injecting adrenalin. Arterial pressure, —@— e@-—; femoral inflow, --@--@--. «a, injecting 6.0 ce. adrenalin, 1: 1000; b, injecting 6.0 ec. adrenalin, 1: 1000; c, heart irregular; d, heart seems to be fail- ing; e, heart improving; f, trachea clamped until animal dies. This injection, also, practically stopped the femoral inflow. And similarly, the inflow rate, after the termination of the injection, started almost at once to increase; but it soon decreased again to begin a slower ascent. The parts of the inflow curve between the termination of the second injection and about 5:00 may be regarded as picturing a, the recovery of the vasoconstrictor mechanism from the peripheral action of the adrenalin (1st ascent); b, the stimulation of the center by the low arterial pressure (1st descent); c, the giving way of the center under the influence of the low arterial pressure of 40 mm. Hg. (2nd ascent); and finally, d, the recovery of the center as the arterial pressure rises (2nd descent), the cen- ter here being stimulated by the low arterial pressure to maintain a high grade of constriction. As the animal seemed to be recovering from the second dose the experiment was terminated by clamping the trachea, at f. The preliminary as- 348 JOSEPH ERLANGER AND HERBERT S. GASSER phyxial constriction followed by complete failure of the constrictor center is readily discernible in the chart. In this experiment, therefore, the injection of adrenlin, 1: 1000, at the rate of about 0.04 ce. per second failed to produce shock. The circulation was, however, distinctly damaged by each of the injections, as evidenced by the low arterial pressure and the high tone of the center that finally developed. The experiment gives no clue to the cause of the disturbance, except to indicate that a part of the effect of the second dose probably was exerted through the heart. Experiment 42 (fig. 2). The first injection (5 ec. of 1: 1000 adrenalin in 22 min- utes, dog weighing 6 kilo) raises the arterial pressue from 107 to 140 mm. Hg. After the completion of the injection the arterial pressure falls in 12 minutes to 67 mm. Hg. and then rises more slowly to about 90 mm. Hg. where, practically, it remains. 3:00 4:00 5:00 5:30 Fig. 2. Experiment 42. Effect of injecting adrenalin. Arterial pressure, —@— ee; femoral inflow, --@--@--. a, injecting 5.0 ee. adrenalin, 1: 1000; b, heart irregular; c, injecting 7.5 cc. adrenalin, 1: 1000; d, heart irregular. During and immediately after the injection, the inflow (femoral) is practically nil, but in 12 minutes it has returned almost to the initial level. Subsequently, however, the inflow rate falls somewhat. As in the preceding experiment, there- fore, when the conditions become constant after the injection, the vasomotor tone is high, yet the arterial pressure is somewhat depressed. Evidently the circula- tion has been hurt; even under the influence of a vasomotor constriction the arterial pressure is subnormal. The second dose consisted of 7.5 ec. of 1: 1000 adrenalin; it was given in 23 minutes. Although it constricts the arteries even more markedly than did the first dose, yet the arterial pressure does not rise so high; and despite continuation of the constriction, the arterial pressure falls during the terminal part of the in- jection as well as subsequently. At the time the experiment was terminated the inflow rate was increasing, but still was well below normal, and the arterial pres- sure was falling. The heart became irregular during the injection and remained so almost to the end. It is doubtful if the fall in pressure can be attributed to this effect of the adrenalin upon the heart, for when the heart eventually became regu- CIRCULATORY FAILURE DUE TO ADRENALIN 349 lar the blood pressure did not improve. Presumably the process would have gone on to death if the experiment could have been continued longer. In this experiment the cause of the low arterial pressure is not definitely deter- minable; it probably is not due to the effect upon the heart, and certainly not to peripheral dilatation. By exclusion, therefore, a diminution in blood volume seems to be the disturbing factor. Experiment 43 (fig. 3). In this experiment the jugular and portal venous pres- sures were followed in addition to the arterial pressure and the femoral inflow. The dog weighed 5.8 kilo. The injection of 8 ce. of a 1: 1000 solution of adrenalin in the course of 28 minutes at first raised the arterial pressure from 100 to 140 mm. Hg., but the pressure soon fell to 122 and after some 21 minutes began to fall again and at such a rate that, by the completion of the injection, the arterial pressure was back to its initial level, and still was falling. It had fallen to 90 mm. Hg. when, without any apparent cause or warning, respiration stopped, c. Ar- . x * a ‘@cc-s e---- ea o=2@-470°8" -® 2:00 3:00 Fig. 3. Experiment 43. Effect of injecting adrenalin. Arterial pressure, — @— @—; femoral inflow, - - @- - @- -; portal pressure, — O— O—; jugular pres- sure, X X x. 4, injecting 8.0 cc. adrenalin, 1: 1000; b, heart irregular; c, respira- ‘tion stopped, artificial respiration started; d, heart stopped. tificial respiration, without ether, was immediately inaugurated. The arterial pressure abruptly fell 20 mm. Hg. but rose again, presumably under the influence of the artificial respiration and possibly also of a change in the character of the heart beat, to 127 mm. Hg. This pressure was maintained only as long as the changed heart beat lasted,—about 2 minutes; then the arterial pressure fell back to, indeed, somewhat below the level from which the sudden rise had started. Shortly thereafter, however, the heart very suddenly and unexpectedly stopped beating. We are of the opinion that in this case the sudden cessation of respira- tion and also the sudden stoppage of the heart were due to the direct and separate action of the adrenalin upon the medullary center and upon the heart. Whether this action was exerted directly upon the organs in question or indirectly through their blood vessels is a question that must be left open. This statement is made in full knowledge of the almost universal belief that adrenalin has but little action upon the blood vessels of these organs. We will have occasion to refer to this topic again. 350 JOSEPH ERLANGER AND HERBERT S. GASSER The femoral inflow was practically stopped by the injection. It did not in- crease materially until the animal died, and it was still far below normal even 25 minutes after death. The fact that the inflow accelerated perceptibly at the moment the animal died may be taken to mean that during life the peripheral action of the adrenalin had been reinforced somewhat through central action. It is obvious, however, that in experiments of this character it matters little what the center may be doing,—for the vessels are maximally constricted by the direct action of the adrenalin. The injection raised the portal pressure promptly from 10.5 to 15.5 mm. Hg., but in the course of 9 minutes it dropped back practically to the original level. It then slowly rose to 13 mm. Hg., fluctuated slightly at the time respiration stopped, and then fell after death, though no more rapidly than before. Although these observations on the portal pressure cannot be interpreted in the absence of information with regard to the simultaneous behavior of the splanch- nic, at least, if not also of the hepatic, resistance, they are none the less of some value in that they indicate that a high portal pressure is not the cause of the cir- culatory disturbance. The height to which the portal pressure is raised here is not sufficient, presumably, to cause a dangerous retention of blood in the portal area. The jugular pressure, excepting one reading made shortly after beginning to give the adrenalin, falls progressively during and subsequently to the administra- tion of the adrenalin. It mounts again, and quite rapidly, at the time respiration fails. This was probably caused by the pressure of the artificial respiration, and in part by the failure of the heart. It should be noted that the inception of the cardiac irregularity, a, is without effect upon the jugular pressure. This fact may be taken to mean that the arrhythmia did not reduce the effectiveness of the heart as a pump. In this experiment, therefore, the fall in arterial pressure occurring between the termination of the injection and failure of the heart cannot be attributed to loss in arterial tone, for the arteries are markedly constricted (unless other areas do not behave as does the femoral area, and of thismore later); and probably not to failure of the heart, for then the jugular pressure would have risen, as it did when the heart actually failed at the end; nor to accumulation of blood in the portal area, for the portal pressure is not high enough to hold out of the general circulation enough blood to dangerously reduce the volume of blood in cireula- tion; nor to the accumulation of blood in the systemic veins, for the jugular pres- sure is not increased. We are then forced to ascribe the fall in arterial pressure to a reduction in the volume of blood returned to the heart. Experiment 44 (fig. 4) gives amore prolonged picture of the after-effects of adre- nalin injection. Thesame observations were made asin the preceding experiment. The injection of about 8 ec. of 1: 1000 adrenalin in the course of 21 minutes into a dog weighing 7.5 kilo, but exceedingly fat, raised the arterial pressure from 84-95 to 154mm. Hg. If we neglect some variations that seem to be of no present sig- nificance, the arterial pressure then fell with a constantly diminishing rate until the end of the experiment approached. The animal died presumably through eventual, though gradual, failure of the respiration. With the failure of respira- tion and the consequent failure of the heart, the arterial pressure of course, fell more rapidly again. CIRCULATORY FAILURE DUE TO ADRENALIN 351 The femoral inflow was practically stopped by the adrenalin. The peripheral vessels began to dilate appreciably only some 40 to 50 minutes after terminating the injection, and only an hour before respiration failed. At the moment of death the inflow rate was still far below the initial level. In this experiment, again, we see the effect of final failure of the center upon the tone of the peripheral vessels; the dilatation occurring at this time proves that the constriction is only partly due to the peripheral action of the adrenalin. The low arterial pressure presumaz bly so stimulates the center as to cause it to maintain a higher grade of constric- tion than the peripheral action of the adrenalin alone is capable of maintaining. It can also be seen that the arteries are not completely dilated even 1 hour 20 minutes after death. In large part this slow port-mortem inflow rate is due to something transpiring in the main artery; for the inflow rate into the unclipped ar- tery is only a bit faster than the inflow rate into the clipped artery. The first impression one gains upon encountering this phenomenon is that a clot has formed in the main artery. But this can not be the case, for with death there is always Fig. 4. Experiment 44. Effect of injecting adrenalin. Arterial pressure, —@e—e@-—; portal pressure, — O— O—; femoral inflow, --@--@--; jugular pressure, x x x. 4, injecting 8.0 cc. adrenalin, 1: 1000; b, heart very irregular; c, respiration diminishing. an acceleration similar to the one here seen. This would be impossible if the slowing were due to the presence of a clot. The adrenalin promptly raises the portal pressure from 8.0 to 9.5 to the as- tounding height of 27.0 mm. Hg.; but the pressure immediately begins to fall and by the end of the injection period it has returned within the initial range where, to all intents and purposes, it remains for about an hour. But finally, and de- spite the gradual dilatation of the leg (and also, presumably, of the intestinal) arteries, the portal pressure falls well below its initial level. The jugular pressure rises during the injection period from about -0.5 to 1.0 mm. Hg. where it remains with inconsequential fluctuations until the heart prac- tically ceases to beat, when it rises to3.5mm. Hg. There is no obvious change in venous pressure in association with the beginning and the termination of the period of cardiac irregularity such as might be expected if the irregularity were associ- ated with a change in the efficiency of the heart. In this experiment, to summarize, the arterial pressure falls despite a strong peripheral constriction and despite a portal pressure, which, excepting only the doz JOSEPH ERLANGER AND HERBERT S. GASSER period of injection is normal or below normal. To the eye the mesenteric veins, in this case, seemed to be small. There is a slight rise in jugular pressure as a re- sult of the adrenalin injection. This might be considered as the expression of an accumulation of blood in the systemic veins, due either to diminution in the ef- ficiency of the heart or to a diminution in the capacity of the arteries. The heart was irregular for a time, but the record is without evidence that this irregu- larity interfered with the work of the heart. An insufficient supply of blood to the heart seems, therefore, to be the only factor remaining to account for the fail- ure of the circulation. This animal was definitely in shock during the last 50 minutes of the experiment. Experiment 46 (fig. 5). In this experiment the intestinal inflow was followed instead of the femoral inflow. The dog weighed 7.9 kilo. The first dose of adre- nalin was 9 ce. of 1 : 1000 in the course of 28 minutes. It raised the arterial pres- | | | | | | | | | | | | | el alah ei Witte 0 Hr. 12300 00 2:00 3:00 Fig. 5. Experiment 46. Effect of injecting adrenalin. Arterial pressure, — @— @—; portal pressure, — O— O--; intestinal inflow, - -@--@--; jugular pressure, x x x. a, injecting 9.0 ce. adrenalin, 1: 1000; 6, brief pause to refill syringe; c, injecting 11.0 ce. adrenalin, 1: 1000; d, heart irregular; e, respiration slowing; f, starting artificial respiration. sure from 100 to 180, indeed, to190 mm. Hg. Before the completion of the injec- tion the arterial pressure began to fall and, barring certain fluctuations which do not concern us here, it declined gradually to its initial level, when the second dose was administered. The intesinal inflow rate was markedly decreased during the injection, but it did not fall quite to zero. It increased subsequently and became normal in the course of 47 minutes. But then, corresponding with a definite rise in the arterial pressure, the peripheral resistance again increased. The portal pressure was markedly increased by the injection and it remained high, though irregular, subsequently. The jugular pressure did not fluctuate more than 0.5 mm. Hg. during the entire course of the experiment, not even when the heart was irregular and the respiratory rate slow. At 1:10 a series of interesting, though perhaps irrelevant waves in arterial and portal pressure was registered. In the original record it can be seen that the + al ¢ _ | CIRCULATORY FAILURE DUE TO ADRENALIN 353 pressure in the splenic (portal) vein rises very abruptly at the instant the arterial pressure begins to fall. It is to be presumed, therefore, that the cause of this phase of each wave is a splanchnic dilatation. The circulatory conditions were not quite normal when the second injection of adrenalin was begun. The arterial pressure, to be sure, was about normal, but this normal level was maintained apparently through over-activity of the vaso- motor center; and the portal pressure (18 mm. Hg.) was considerably above the initial level. Inasmuch 4s the intestinal arterioles were somewhat constricted at this time, it follows that the high portal pressure must be attributed to a con- tinued high portal resistance. The conditions with respect to the portal pressure following the first injection evidently were very different from those heretofore observed: they were favorable to the retention of blood in the abdominal viscera. Yet the circulation showed no definite evidences of failing. The second injection of adrenalin (11 ec. of 1: 1000) now raised the arterial pressure to 152 mm. Hg.: but then, despite the continuance of the injection, the pressure steadily fell and the heart stopped about 13 hours after terminating the injection. The intestinal inflow dropped practically to zero and showed very little tendency to increase even after the animal died. By the test described in another place (8) it was found, shortly after the completion of the second injec- tion, that the slowing of the inflow rate was due to constriction of the main inflow artery. The portal pressure rose irregularly during the injection period and then fell steadily, crossing the pre-injection level after about 20 minutes had elapsed. The fall in the portal pressure undoubtedly was due to the coincident fall in the arterial pressure. The possibility that the fall in the arterial pressure in experiments of this char- acter is due to dilatation in the splanchnic area while the somatic (femoral) area is constricting, finds no support in the results of this experiment, Furthermore, the failure of the jugular pressure to change materially seems to exclude an ac- cumulation of blood in the systemic veins through functional incapacity of the heart as a factor in the failure of the circulation. This is the first experiment in which the portal pressure has remained at a high level during most of the injec- tion and post-injection periods. Therefore, in this case the possibility that the failure of the circulation is due to accumulation of blood in the portal area can- not be excluded, though, as has been said, the portal pressure after the first injec- tion remained high and yet the circulation was satisfactorily maintained. It is recorded in the notes that the mesenteric veins were distended. Experiment 48 (fig. 6). The intestinal inflow was followed in this experiment also. The animal weighed not over 7 kilo and received a large dose of 1: 1000 adrenalin (about 11 cc. in the course of 21 minutes). The arterial pressure was elevated at once from 100 to 170 mm. Hg.; it then immediately began to fall. With the exception of two irregularities this fall, upon the whole, was steady, and in the course of 23 hours carried the arterial pressure down to80 mm. Hg. Of the two irregularities in the pressure fall, the first was a fall and rise in association with a very decided temporary slowing of the respiration,e. Webelieve these two events were causally related and are indicative of some transitory central change. It will be noted that at this time, judging by the inflow rate, the adrenalin action was at it height. The second change consisted of an abrupt rise in the arterial pressure which undoubtedly is to be attributed to the disappearance of the heart 3504 JOSEPH ERLANGER AND HERBERT S. GASSER irregularity, b, which had persisted almost from the very beginning of the injection. The inflow rate decreased during the injection, reaching zero with the first estimation after the cessation of the injection. It then gradually increased, but even 2 hours later it was still decidedly below normal. The portal pressure at first rose from 5 to 18 mm. Hg., fell somewhat, and then rose to attain a second crest about 70 minutes after beginning the injection. It then fell more or less steadily. The form of this part of the portal curve obviously is influenced by the arterial pressure. The fall in arterial pressure is not, however, the sole cause of the fall in portal pressure; for while the arterial pressure falls from 107 to 80 mm.,a ratio of 1.3 to 1, the portal pressue falls from 16 to5 mm., a ratio of 3.2tol. In other words, the portal pressure falls faster relatively than the arteria! pres- sure, and this more rapid fall in portal pressure occurs despite a progressive dimi- Hr. 12:00 1:00 , 2:00 3:00 4:00 Fig. 6. Experiment 48. Effect of injecting adrenalin. Arterial pressure —@— @—; portal pressure, — O— O—; jugular pressure, x x x; intestinal in- flow, - - @- - @-- (for the readings marked by the sign (—) the inflow pressure was on a much higher than the usual level). a, injecting 11.0 cc. adrenalin, 1: 1000; b, heart irregular; c, respiration slow; d, injecting 11.0 ce. adrenalin, 1: 1000; e, heart irregular; f, change in type of heart irregularity; heart regular subse- quently; g, artificial respiration; the heart at this time was beating periodically. nution in the splanchnic resistance which ordinarily would tend to raise the por- tal pressure. To be in a position to interpret these changes in the portal pres- sure it would be necessary to know also the state of the portal resistance in the liver. Since this information is not at hand a decision with regard to the cause of the more rapid fall in the portal pressure cannot be reached. The continuous fall in arterial pressure probably is not due to increasing in- capacity of the heart. The jugular pressure to be sure is raised somewhat (1 mm.) during the administration of the adrenalin, but later it falls below the initial level; and though the heart beat under the influence of the adrenalin becomes ir- regular, this irregularity, b, does not persist. A second dose of adrenalin, similar to the first, was now given. At this time the circulation had by no means returned to its initial state. The arterial pres- sure, despite a relatively high peripheral resistance, was at least 20 mm. Hg. below normal. Whether conditions would in time have become normal is a ques- CIRCULATORY FAILURE DUE TO ADRENALIN ) “B58 tion that cannot be answered. The portal pressure, though, had returned to its initial level. Asa result of the injection the arterial pressure rose to 156 mm. Hg. and the heart became irregular. The arterial pressure then fell steadily until, 40 minutes later, a change in the character of the heart irregularity, f, apparently caused the pressure to rise slightly; another and greater rise occurred 10 minutes later when the heart beat became regular. The fall in arterial pressure was then resumed, a decrease from the level of 144 to 57 mm. Hg. taking place in the course of 30 minutes. The heart then exhibited a peculiar type of irregularity, the na- ture of which does not concern us here. The intestinal inflow rate was cut down by the injection almost to zero, and had not begun to increase even 90 minutes later, when the heart became irregular. 2 = oe 2 2.0 200 15 150 1.0 100 05 50 12:00 1:00 2:00 3:00 Fig. 7. Experiment 49. Effect of injecting adrenalin, small and large doses. Arterial pressure, — @— ®@—; portal pressure, — O— O—; jugular pressure, x x x; intestinal inflow, - - @- - @- - (for the readings marked by the sign (—) the inflow pressure was on a much higher than the usual level). a, adrenalin injection started and discontinued; b, injecting 11.0 cc. adrenalin, 1: 10,000; c, injecting 11.0 ec. adrenalin, 1: 1000; d, heart irregular; e, respiration markedly slowed, stopped at f; g, artificial respiration started. The portal pressure was permanently elevated by the injection; it showed some slight fluctuations which were always of the same sign as the large fluctuations in the arterial pressure. Here, therefore, the arterial pressure falls despite a high peripheral resistance and despite the absence of any evidence of cardiac failure. The portal pressure, however, remained high during most of the experiment. Therefore, the possibility that the fall in arterial pressure is due to the accumula- tion of blood in the splanchnic veins cannot in this case be excluded. Experiment 49 (fig.7). This experiment was performed primarily for the pur- pose of comparing the effects of small with the effects of the large doses of adre- nalin given in previous experiments. The first attempt to inject 1: 10,000 adre- nalin, a, had to be discontinued on account of an accident. Then, after the cir- culation had returned to its previous state, 11 ce. of 1: 10,000 adrenalin were given 506 ~ JOSEPH ERLANGER AND HERBERT S. GASSER over a period of 28 minutes, b. During the injection period the arterial and por- tal pressures, as usual, were raised, the intestinal inflow rate slowed. Though this is also the result commonly obtained with the larger doses there are, never- theless, certain outstanding differences. These are,—the steady rise in arterial pressure, the absence of any tendency on the part of the portal pressure to fall after the preliminary rise, and the incompleteness of the peripheral constriction. In the period subsequent to the injection, the striking differences are,—the im- mediate relaxation of the arterioles beyond their initial size, with a return to the normal inflow rate in the course of 20 minutes; the immediate descent of the ar- terial pressure to a subnormal level with a relatively rapid recovery to the normal; and the almost immediate return of the portal pressure to the normal level. The circulation became normal in every respect. The second injection consisted of 11 ec. of 1: 1000 adrenalin; it was given in the course of 24 minutes, c; this dose, therefore, was about ten times as large as the first dose. The arterial pressure rose to the unusual height of 216 mm. Hg., but, as usual, began to decline before the injection was completed, and at about the time, d, the heart became permanently irregular. Slightly later, e, the respira- tions became very slow and this slowing increased until the breathing stopped altogether, f. The heart stopped after the respiration, and despite the inaugura- tion of artificial respiration, g, before the heart had actually stopped. By the time the respiration stopped the arterial pressure had fallen to 84 mm. Hg. The inflow rate fell practically to zero when the injection of adrenalin began, aud it remained there until theanimaldied. Thensomerelaxation occurred, indi- cating that the previous constriction, though mostly due to the peripheral action of the adrenalin, had also been maintained in part by central action. The portal pressure was instantly increased by the adrenalin but immediately began to decline, while showing some fluctuations in correspondence with those of the arterial pressure. It was subnormal during a large part of the period. The jugular pressure was markedly increased; for this it is possible that both the altered respiration and heart action were responsible. It can scarcely be maintained that this animal was brought into a state of shock; but it is of significance that at the end the arterial pressure was somewhat subnormal despite an intense arterial constriction. Death was due to some action of the adrenalin, direct or indirect, upon the respiratory center. Summary and discussion of experimental data Now, with a variety of results before us, an attempt will be made to ascertain the usual reactions to the injection of adrenalin and the sig- nificance of those reactions in relation to the shock problem. 1. Action on the arterial pressure. The arterial pressure during the injection period invariably is high, and higher during a first than during a second injection. When the dose is relatively small the arterial pres- sure usually is consistently high (figs. 2, a and 7, b); but when the doses are large the pressure usually begins to fall before the end of this period (figs. 4,a; 5, a; 6, a). One gains the impression that the larger the dose CIRCULATORY FAILURE DUE TO ADRENALIN _— - 357 the earlier and the more profound is this fall in pressure apt to be. It always is more marked after a second than after the first dose. The decline during the injection period, though, usually falls short of carry- ing the arterial pressure back to its initial level. These differences in the effect of dosage on the arterial pressure may depend in part upon differences in the action of the adrenalin upon the heart; but that the fall in pressure is not wholly dependent upon the behavior of the heart is indicated by the fact that it may begin before the irregularity (fig. 4) and may not occur when the heart becomes irregular (fig. 2, b). A second large dose never raises the arterial pressure as high as did the first dose, provided it also was large. After the administration of a small (fig. 7, b) or of a moderate dose (fig. 1, a) the arterial pressure usually falls rather abruptly to a sub- initial level, and then mounts slowly, eventually reaching normal, after small doses (fig. 7, b), but usually not regaining the normal level after moderate doses (figs. 1, a; 2, a). A second dose that produces approxi- mately the same immediate reaction, leaves the arterial pressure still lower (fig. 1,c). After a large first dose, barring accidental occurrences, the fall in arterial pressure begun during the injection period continues without any break to mark the conclusion of the injection (figs. 4, 5, 6), it may be, until the animal dies (fig. 4); though this is more commonly seen after a second large dose (figs. 2, 5,6). A decline of this character that does not kill, tends to terminate below the initial level (figs. 5, a; 6, a). So far as can be judged by the arterial pressure, therefore, large doses of adrenalin do long-lasting damage to the circulation, if they do not actually carry the pressure down to a dangerously low level. 2. Action on the peripheral resistance. Without exception the re- sponse to adrenalin during the injection period has been a marked peripheral constriction causing, in the case of the larger doses, prac- tically a complete cessation of inflow (figs. 2, 3, 4, 5, 6, 7). After terminating the injection of a small dose (fig. 7, b) the resist- ance quite promptly decreases to, or slightly below, normal; after a moderate dose (figs. 1, 6; 2, a) the relaxation that occurs is apt to be slower and short of complete return to normal; while after large doses, and often after moderate doses given a second time, the relaxation is very slow and usually very far from complete even after two hours or more have elapsed (figs. 4; 5, c; 6, d). This long-lasting constriction, however, usually is not wholly due to direct action of the adrenalin upon the blood vessels; a part of the tone is central in origin as is evidenced by the acceleration of dilatation that usually occurs at the moment 358 JOSEPH ERLANGER AND HERBERT S. GASSER the animal dies (figs. 3, 4, 7). The splanchnic and the femoral areas are alike in their response to these doses of adrenalin. In one experi- ment (fig. 1, a) the constriction of the period of injection gave way very rapidly to an extreme dilatation, followed at once by a gradually developing constriction which probably was central (compensatory) in origin. The literature on the action of adrenalin on the blood vessels has re- cently been reviewed by Hartman (4). There the statement occurs that ‘‘dilatation in the blood vessels of skeletal muscles is the usual re- sponse to adrenalin in animals.’’ Dilatation is also said to occur in the intestinal vessels, especially after large doses (5), (6). Our findings do not agree with these statements. To be sure, the method we have em- ployed in following the peripheral resistance furnishes discontinuous in- formation; and if very brief periods of dilatation occur during the con- tinuous injection of adrenalin there is the possibility that our method might fail to detect them. The fact, however, that we have never en- countered dilatation during the injection of adrenalin certainly renders this possibility a very remote one, indeed. In the post-injection period, as has been said, we have encountered striking and momentary dilata- tion, but only once (fig. 1, a); and a very slight transitory dilatation, also, only once (fig. 7, b). With these exceptions, the constriction pro- duced by both moderate and large doses has always outlasted the injec- tion period, in some of the instances as long as 2 hours. Hoskins, Gunning and Berry (7) found that adrenalin in “all’’ doses ' eonstricts the skin vessels but not those of the muscle. Later, how- ever, Gunning found (8) that massive doses of adrenalin slow the blood flow through muscle. This correction suggests that all of the discrep- ancies depend merely upon dosage and method of administration. However this may be, it is certain that the constriction we have ob- served is so marked that it cannot, in the case of the femoral readings, be accounted for on the basis of a constriction affecting the skin vessels alone. Gruber (9) fails to obtain dilatation of the blood vessels of muscle shortly after section of the nerve; neither, apparently, does he, under such circumstances, obtain constriction. Even, therefore, if it were ad- mitted for purposes of argument that we get constriction because the nerves have been injured (and such experiments as 41 [fig. 1, 2nd injec- tion] conclusively show that constriction is obtained when the nerves unquestionably are active), the reduction in inflow rate that we obtain is far too great to be referable to constriction of the skin vessels alone. CIRCULATORY FAILURE DUE TO ADRENALIN 359 But whatever the cause of the discrepancy, we can assert a, that our method of determining the effect of the adrenalin upon the peripheral resistance is free of the ambiguities that attach to the outflow and pleth- ysmograph methods employed by other investigators; 6, that our method demonstrates that in the dosages we have employed constric- tion of both the somatic and the splanchnic areas is the main if not the only effect of the continuous injection of adrenalin; and c, that this con- striction often persists for hours after the dose has been administered, partly, perhaps, as a central compensatory response to the low arterial pressure, or to a tendency to a low arterial pressure. Our method of following the vasomotor tone does not help to disso- ciate the factors, central and peripheral, upon which the constriction depends. There is, of course, no doubt but that during the injection of the adrenalin any part the center may be playing in maintaining the constriction must be insignificant in comparison with that effected by local action. That the center, however, is a factor in maintaining the constriction subsequent to the injection is indicated by the acceleration of the recession of the constriction that often occurs at the moment the animal dies. But even with death the dilatation is relatively slight. This failure of the injection rate to return to, and then to pass beyond, the initial value probably is a manifestation of the phenomenon that has already been described as occurring at the termination of long ex- periments in which no adrenalin whatever has been employed (3), and which we felt might be related to the phenomenon of post-mortem con- traction described by MacWilliam (10). In the present experiments, however, it is possible that the long-lasting constriction is due to the direct action of the adrenalin upon the walls of the large arteries (11). 3. The systemic venous pressure. Our method of measuring the ve- nous pressure gives, to all intents and purposes, the pressure in the right auricle. - Pressure changes here are of course slight at best, and are af- fected not alone by the force from behind and by the capacity of the heart to empty itself, but also by variations in the effectiveness of the respiratory pump. It is not surprising, therefore, that the literature on this subject is contradictory. Thus Bainbridge and Trevan (12), for example, find that the pressure in the vena cava is not altered by the injection of adrenalin; whereas Schmid (13), Elliott (11) and Edmunds (15) say it is elevated. Our results in this respect have been quite inconstant. In one ex- periment (fig. 5), the jugular pressure changed but little; in two (figs. 3, 6) it fell; and in two instances (figs. 4, 7) it'rose. In both of the last, 360 JOSEPH ERLANGER: AND HERBERT S. GASSER though, there were two possible and perhaps unusual causes for the rise. One cause was a change in the character of the respirations: in one case (fig. 4) this change was slight and the venous pressure was elevated but little; in the other (fig. 7), the respiratory change was very marked and the rise in venous pressure also was marked. The other possible cause of the rise in venous pressure is related to the effect the adrenalin had on the portal pressure. For these two experiments were exceptional in that after the injection the portal pressure (see below) quickly resumed its normal level. The marked constriction of the arterioles caused by the adrenalin and the relative emptiness of the portal veins that a nor- mal pressure in them bespeaks, together might have had the effect of distending the systemic veins. But whatever the cause of the incon- stancy of the jugular pressure may be, it is obvious that it permits us to conclude only that the heart as a rule is capable of moving on the blood that is brought to it. Action on the heart. In many of the experiments there were indica- tions of deleterious action of the adrenalin upon the heart, the heart developing a very marked irregularity either while the adrenalin was being injected or subsequently. This irregularity was not of the kind that is produced by vagal action. The arterial pressure at these times occasionally (figs. 1, d, e; and 6, b) gave evidence that the heart was not as efficient as when it was beating regularly; at other times, however, the inception or the disappearance of the irregularity was without ob- vious effect upon the arterial pressure. Furthermore, with but one pos- sible exception (fig. 7, 2nd dose), the jugular pressure failed to exhibit with the inception and disappearance of this irregularity, the altera- tions that are taken to indicate diminishing or increasing capacity of the heart for work. No effort has been made to ascertain the nature of the irregularity. . But whatever it may be, it seems justifiable to con- clude that failure of the heart is not an important factor in the gradual failure of the circulation after the administration of adrenalin. The sudden stoppage of the heart that occasionally has occurred while the arterial pressure still was sufficient (figs. 3 and 7) may have been caused by some direct action of the adrenalin upon the heart. But this is a question that does not concern us here. - Action on respiration. The adrenalin in almost every instance has had a marked effect upon the respiration. This has consisted a, of transitory slowing (fig. 6, c); b, of progressive slowing of the respiratory rate (figs. 4, c; 5, e), sometimes leading to surprisingly low rates (6 per minute in fig. 7); or c, of stoppage of respiration, sometimes sudden (fig. CIRCULATORY FAILURE DUE TO ADRENALIN 361 3, c), Sometimes preceded by slowing (fig. 5, f). The administration of artificial respiration in the latter instances at most has delayed death only a few minutes (figs. 3, 5). Therefore, lack of pulmonary ventila- tion can scarcely be regarded as the cause of death or of the breakdown of the circulation. It is not the purpose: of this paper to discuss the cause of failure of the respiratory center. The portal circulation. Except, perhaps, its action on the peripheral resistance, the most interesting effects of adrenalin are those it exerts upon the portal circulation. The first effect of the injection of adre- nalin invariably is to raise the portal pressure, it may be as high as 28 (fig. 5) or 30 (fig. 6) mm. Hg., though usually to not over 15 mm. Hg. The portal pressure then usually falls practically to the initial level a, either during the injection (figs. 3 and 7, 2nd dose), or 6, immediately (figs. 4 and 7, Ist dose) or some time after (fig. 6); and c, while the ar- terial pressure is still well maintained (fig. 6, Ist dose) or d, not until the arterial pressure falls to quite a low level (fig. 5, 2nd dose). In all of these cases there is a certain, although by no means complete, paral- lelism between the portal pressure and the arterial pressure. In one case (fig. 5, Ist dose) the portal pressure remained high even after the arterial pressure had returned to the initial level. The very marked effects that these doses of adrenalin have upon the portal circulation suggest the advisability of carefully examining them in order to determine whether they are of significance in relation to the failure of the circulation. Physiologically, a continuous elevation of the portal pressure can be effected a, through a rise in arterial pressure; b, through a diminution in arterial resistance in the portal area; c, through a rise in caval pressure; d, through contraction of the musculature of the portal veins themselves; and e, through an increase in the resistance to flow through the liver. a-and b. The injection of adrenalin, of course, raises the arterial pres- sure but at the same time markedly increases the resistance in the ar- terioles. Whether or not the blood flow into the portal area would in- crease, therefore, would depend upon the balance that is struck between these two effects. Our inflow determinations show conclusively that the constriction, in the intestinal area, at least, is so extreme that de- _ spite the rise in arterial pressure the adrenalin must restrict the blood flow. It is, of course, conceivable that the other pathways into the portal system are not constricted by the adrenalin to the same extent as is the intestinal pathway and that it is through the former that the portal pressure is raised. We have no direct observations bearing on this possibility. THE AMERICAN JOURNAL OF PHYSIOLOGY, VOL. 49, NO. 3 362 JOSEPH ERLANGER AND HERBERT S. GASSER The measurements of the blood flow in the portal veins as effected by adrenalin that are recorded in the literature help to settle this question, though.the effects of brief injections only have been studied. With large doses Schmid (13) invariably obtained a marked reduction in blood flow in the portal vein; in one of his instances the blood flow stopped completely for a few seconds. On the other hand, Burton-Opitz (14) finds an increase in portal flow during the phase of high arterial pressure. This increase, though, was never very striking, and evidently very in- constant, as may be indicated by the following values taken from his published data: BLOOD FLOW, CUBIC CENTIMETERS PER SECOND EXPERIMENT NO. Before At crest of arterial pressure 3 4.50 4.54 4 3.05 3.20 5 3.43 3.37 3.25 2.56 Upon the whole, it seems fair to conclude that the blood flow through the portal area is not increased during the prolonged administration of adrenalin. Granting this, it follows that adrenalin constricts the whole of the splanchnic bed. The rise in portal pressure, therefore, is refer- able neither to a premised splanchnic dilatation nor to the rise in ar- terial pressure; though, of course, during the period of constriction, variations in arterial pressure must effect variations of the same sign in the portal pressure. c. It has already been pointed out that the systemic venous pressure ordinarily is not increased by the prolonged injection of adrenalin; therefore we must seek elsewhere for the cause of the high portal pressure. d. Edmunds (15) has observed that strips of the portal vein contract when immersed in a solution of adrenalin. Occasionally we have ob- served during the height of the adrenalin action, a sausage-like appear- ance of the branches of the portal vein, rings of constriction so complete as to quite obliterate the lumen and to offer an appreciable resistance to the passage of the blood, alternating with segments filled with blood. If this were constant in occurrence it might help to explain the high pres- sure recorded in the splenic vein; but in many instances these evidences of contraction of the veins are absent. CIRCULATORY FAILURE DUE TO ADRENALIN 363 e. If constriction of the large portal radicles is not the cause of the high portal pressure there remains as the only possible explanation of the condition an increase in the resistance to the passage of blood through the liver. This question has recently been discussed by Bainbridge and Trevan (12). The possibilities in the case are: a, constriction of the minute portal radicles in the liver; b, constriction of the hepatic or sublobular veins; and c, narrowing of the hepatic capillaries. Bain- bridge and Trevan are disposed “to regard narrowing of the capillary channels by swelling of the liver cells as the most probable explanation of the obstruction produced by adrenalin to the blood flow through the liver.””’ The evidence they offer in favor of this view is that adre- nalin causes the liver volume to increase, while histological examination of clamped-off pieces of liver shows the interlobular and intralobular veins to be engorged with blood. Our own experiments throw relatively little light on the condition of the blood vessels of the liver. We have not examined the liver during the height of the adrenalin action. The gross appearance presented by the liver at the close of experiments has been rather variable. Occa- sionally all of the marks of engorgement are evident; more often its edges have been sharp, though in such instances the parenchyma on section often seemed to be bloody. In one case we weighed the liver and found it to be at the lower limit of the normal range. Microscopi- cal examination has been made in only one case and that was one in which the liver at autopsy was found to be engorged. In this instance the hepatic capillaries, upon the whole, were dilated and contained an excess of blood. The corpuscles did not seem to be so closely packed as they are in the intestinal vessels of shocked animals. The liver cells were not swollen. It is inconceivable, indeed, that the liver cells could swell so rapidly under the influence of adrenalin as to cause the practically instantaneous increase in liver volume and portal pressure which are pictured by Bainbridge and Trevan, the more so when it is recalled that even a com- paratively small dose of adrenalin may cause a marked increase in por- tal pressure (see fig. 7,a and 6). As a matter of fact, we are not con- vinced that the method employed by Bainbridge and Trevan for the purpose of following the volume of the liver is entirely satisfactory. For an increase in arterial pressure, by increasing the turgidity of the liver lobes, might, depending upon conditions, increase the pressure upon the balloon between the lobes. However this may be, the com- plete parallelism of their “‘volume’’ and pressure curves to each other 364 JOSEPH ERLANGER AND HERBERT S. GASSER make it incumbent upon them to prove that they are actually recording volume changes. Better methods (15) seem to indicate that in the dog, at least, the liver volume is reduced by small, brief intravenous injections of adrenalin. If it could be shown that the engorgement of the liver that sometimes occurs after the administration of adrenalin is slow in development, another possible cause of the swelling of the liver cells and of the engorgement of the liver capillaries observed by Bainbridge and Trevan would be the effect upon the tissues of the marked slowing of the blood stream that accompanies the prolonged injection of adrenalin. The process would then be similar to the one which in our opinion accounts for the engorgement of the intestinal capillaries. Assuming, for purposes of discussion, that the portal action of the adrenalin is the cause of the shock-like failure of the circulation, let us try to discover the mechanisms that might bring it about. 1. When the portal pressure is high, such large amounts of blood might be trapped in the portal area as to lead to serious depletion of the systemic vessels. It is here that the exact location of the increased re- sistance in the liver might be of some significance. For if the obstruc- tion were beyond the capillaries a very much larger volume of blood would be trapped in the portal area than if the obstruction were in the portal venules. Bainbridge and Trevan (12) have suggested that the distention of the liver and portal area might be a contributory factor. But in certain cases, at least, the trapping of blood cannot be sufficient to be the sole cause of circulatory failure, for the rise in portal pressure may be transitory even in cases that die (fig. 4). Furthermore, the liver, at least at the time of death, as has been said, often does not contain more than its normal quota of blood. Nor are the tributary veins of the portal area always distended during the injection; often they seem relatively empty, though the pressure in them may be high. And finally, experiments to be described later show that a mere rise in portal pressure even when maintained for hours does not embarrass the circulation nearly to the same extent as does the administration of adrenalin. : 2. A high portal pressure might reduce the blood volume by increas- ing filtration of plasma. As a matter of fact, Bainbridge and Trevan find that during the prolonged injection of adrenalin the lymph flow through the thoracic duct is increased. There can be no doubt but that the administration of adrenalin increases filtration pressure in the splanchnic capillaries; therefore, a part of the increase in lymph forma- CIRCULATORY FAILURE DUE TO ADRENALIN 365 tion may be accounted for here. But Bainbridge and Trevan, findjng that the lymph “‘becomes slightly more concentrated,’’ conclude that a part of it comes from the liver. This observation they take as further evidence in support of their contention that the portal obstruction is in or beyond the liver capillaries. There is, however, another possible explanation of the increase in concentration of the lymph, and that is that the extreme and prolonged slowing of the blood stream so damages the hepatic capillary walls (as well as those of other organs) that they become more permeable to the plasma. Again, if we admit for the moment that the portal obstruction is in or beyond the portal capillaries, the filtration would be most rapid at the time the portal pressure is highest, which, as a rule, is during the early stages of the injection. The figures of Bainbridge and Trevan show, however, that the lymph flow steadily increases as long as the injection of adrenalin continues. This observation tends to confirm our view that the part of the lymph that increased concentration indicates is formed in the liver, passes out of the blood stream, not as a result of increased filtration pressure, but rather as a result of increased permeability of the capillary walls. But after all, those portions of the blood fluids that reach the thoracic duct play no part in the processes that lead to failure of the circulation, for they soon are returned to the blood stream. Only those portions that are retained in the tissues or in the body cavities are of significance in this connection. We have seen no indications of edema of the or- gans, though during the injection of adrenalin beads of fluid have been seen to form on the surface of the liver. At autopsy the peritoneum occasionally seems to contain a slight excess of fluid. 3. The other striking effect the injection of adrenalin has upon the portal circulation is to slow the blood stream. Here attention should be called to the magnitude of this slowing. The inflow determinations show that even salt solution under a pressure considerably higher than the normal arterial pressure may scarcely flow through either the splanchnic or somatic capillaries during the height of adrenalin action. It is obvious, therefore, that when blood takes the place of salt solution and when two areas of increased resistance (splanchnic and portal) replace the one the inflow has to contend with there can be but little blood flowing through the splanchnic (or the somatic) area. There are, therefore, good reasons, for believing that failure of the circulation after the administration of adrenalin is the consequence, mainly, of changes wrought in the tissues by asphyxia. In favor of this view is the fact that death has occurred whenever the constriction 366 JOSEPH ERLANGER AND HERBERT S. GASSER has been extreme and long-lasting, and that recovery has occurred whenever the dose of adrenalin failed to maintain a high grade of con- striction. Furthermore, the slowing of the circulation in our cases has lasted sufficiently long to lead to failure of the circulation through the same mechanism which, we believe, operates to cause the circulation to fail when the vena cava or the aorta is partially occluded (16). There is, therefore, no need of going outside of this mechanism to find an expla- nation of the failure of the circulation that follows the long-continued administration of adrenalin, though, of course, such trapping of blood and such filtration of plasma as may occur will contribute to that end. Pathology. This conclusion is supported by the autopsy findings, for the most striking lesion found is the same marked dilatation of the capillaries and venules of the villi of the intestines that was found by us In shock as produced by exposure of the abdominal viscera, and by partial occlusion of the vena cava or of the aorta. To be sure, the cir- culatory disturbance resulting from the injection of adrenalin is just the one that would tend to produce this picture, for the high pressure developed in the portal area, at least early in the period of injection, must have the effect of increasing the pressure in the splanchnic capil- laries, notwithstanding the sharp fall in pressure that must occur in the constricted arterioles. But that this probably is not the mechanism by which the dilatation is effected, but rather the slowing of the blood flow, is the conclusion that is justified by the results described in the preced- ing paper of this series (16). In the gross, as well as microscopically, the intestines, stomach and spleen present very much the same appear- ance as they do in shock as induced by the other methods we have employed. Does adrenalin produce shock? Having described and discussed certain of the manifestations of large and long-continued doses of adrenalin the question now arises—are there any reasons for regarding as shock the condition thus induced? If we exclude those cases that die suddenly as a result of stoppage of the respiration or of the heart, we think it can be asserted that at least the type of circulatory failure that is illustrated by experiment 44 (fig. 4), of which we have several instances, in which the pressure gradually falls until the animal dies, bears a close resemblance to the failure of the circulation resulting, for instance, from exposure of the intestines. The fact, furthermore, that animals in this condition may not require an an- esthetic, although the eye reflex is still present, if this sign is of any sig- CIRCULATORY FAILURE DUE TO ADRENALIN 367 nificance, lends additional support to the position first taken by Bain- bridge and Trevan that shock can be induced by adrenalin. We do not agree with Henderson and collaborators in their conclusion (17) that adrenalin causes death only through acute cardiac dilatation or pulmo- nary edema, though it must be admitted that such accidents (at least the former) often bring the experiment to a close before shock-like failure of the circulation has had a chance to develop. THE EFFECTS OF OBSTRUCTING THE PORTAL RADICLES IN THE LIVER Accumulation of blood in the portal area forms the basis of a number of the hypotheses of shock. It is in this way that shock is supposed to result from the splanchnic dilatation of vasomotor paralysis or inhibi- tion; from temporary partial occlusion of the inferior vena cava (18); from constriction or obstruction of the portal hepatic capillaries (12); and from constriction of the latter region and also of the splanchnic capillaries (19). In many of the experiments we have described, a rise in portal pressure, slight and transitory (cava occlusion) or marked and sometimes long-lasting (adrenalin injection), has been a possible factor in the failure of the circulation. In an effort to reproduce as closely as possible the conditions premised by the hypotheses that attribute shock to an increase in portal resist- ance, we have had recourse to a method of obstructing the flow of blood through the smaller vessels that has long been practised in physiology, namely, by injecting into the stream of blood flowing toward an organ a suspension of lycopodium spores. These spores have a rough surface and about three to four times the diameter of the red blood corpuscles, and plug the vessels proximal to the point where they break up into capillaries. The increased resistance is thus placed in the situation in which constriction normally occurs, though, if Bainbridge and Trevan are right in their view (and we do not, as has been seen, regard their evidence as conclusive) that the obstruction occurs in the capillaries of the liver, the amount of blood that the injected spores trap in the portal area will not be quite so great as would be held by complete closure of the capillaries. Method The suspension of lycopodium spores has been injected into the gas- trolienic vein in both the dog and the rabbit. The carotid pressure has been followed in all experiments, and in some of the experiments on the dog the femoral or intestinal inflow rate, the portal pressure and the jugular pressure, also. 368 JOSEPH ERLANGER AND HERBERT S. GASSER Experimental We will describe and discuss our experiments not in the order in which they were done, nor as entities, but in the way that facilitates the de- velopment of the subject. In experiment 53 (fig. 8), the first, and a relatively small, dose of lyeopodium, a, raised the portal pressure from the normal of 8 mm. Hg. to a plateau which, in the course of 70 minutes, declined from 12 to11 mm. Hg. The vasomotor tone was immediately increased and the increase continued for about 25 minutes when, Fig. 8. Experiment 53. Circulatory effects of injecting lycopodium spores into the portal vein. Dog. Arterial pressure, — @—@—+; femoral inflow, --@--@--; portal pressure, — O— O—; jugular pressure, x x x. a,a’, a’, ly- copodium injected; 6, accidental injection of carbonate; c, artificial respiration; d, artificial respiration stopped; e, inflow readings transferred to other femoral; f, heart stopped. upon the whole, it decreased slightly but did not return to the normal level. The arterial pressure was affected but slightly, falling from 110 to 102 mm. Hg. Evi- dently the vasoconstriction sufficed to almost compensate such altered distribu- tion of the blood as was determined by this dose of lycopodium. Then another dose was administered, a’. This raised the portal pressure from 11 to19 mm. Hg. and, barring certain fluctuations, evidently attributable to pass- ing fluctuations in vasomotor tone, this level was maintained for 2 hours. The inflow rate again was decreased. The general trend of the inflow rate during this period was downward, and of the arterial pressure upward. Evidently at the end of the period vasoconstriction perfectly compensated even this degree of portal obstruction. CIRCULATORY FAILURE DUE TO ADRENALIN 369 We may for the present pass by the last part of this experiment and turn to another experiment (no. 60, fig. 9) in which to all intents and purposes a single, moderately large dose of lyeopodium was given. As a matter of fact the lyco- podium was given repeatedly in small doses until the desired grade of obstruction was obtained. The immediate effect upon the portal pressure was a tremendous rise from the normal of 6 to8 mm. Hg., to41 mm. Hg. But in the course of the next 40 minutes the pressure steadily fell almost to 15 mm. Hg. and, excepting temporary fluctuations, again undoubtedly due to temporary fluctuations in the vasomotor tone, the portal pressure did not vary more than 1 mm. above or below 16 mm. Hg. during the course of the next 3 hours 40 minutes, when the experiment was terminated by stabbing the ventricles b. In this experiment the vasomotor tone was followed in the intestines as well as in the leg. We call attention to the fact that the general trend of the tone in these two regions was toward parallel- ism. The parallelism to be sure was not perfect; but when divergences occurred they were not any larger than one would expect considering that the comparable readings were not made simultaneously. Bearing this in mind, it is seen that Fig. 9. Experiment 60. Circulatory effects of injecting lycopodium spores into the portal vein. Dog. Arterial pressure, —@—@—; femoral inflow, -- @--@--; intestinal inflow, - - @- - @- -; portal pressure, —O— O—. 4, inject- ing lycopodium; b, heart punctured. simultaneously with the rise in portal pressure the peripheral resistance increased and the arterial pressure fell, though not morethan 15mm. Hg. During the rapid decline in portal pressure the vasomotor tone diminished but the arterial pres- sure, after recovering somewhat, remained quite stationary. We pause here to discuss the mechanism of these occurrences. It is important to ascertain first why the portal pressure steadily falls after the first rise. This fall cannot be attributed to splanchnic constriction because, during this period, the intestinal arterioles are dilating; nor can it be attributed to a change in arterial pressure, for this is rising slightly or is stationary. Neither can it be explained upon the basis of a fall in systemic venous pressure, for in other experiments (no. 53, fig. 8) it was found that this pressure is altered but little by lycopodium injections. An increase in the capacity of the portal area cannot be 370 JOSEPH ERLANGER AND HERBERT S. GASSER invoked as an explanation of the fall in portal pressure because the change in tone of the arterioles and in the arterial pressure indicates ' that the circulation is improving, which could not be the case if blood were passing out of effective circulation. The only acceptable explana- tion must provide a gradually widening pathway out of the portal area. Three ways in which this might occur suggest themselves: a, The re- sistance to the passage of blood through the portal venules might diminish as a result of the washing out of the obstructing spores; b, the high portal pressure might open up by distention both plugged and unplugged venules. Both of these possibilities are rendered highly im- probable by the fact that the same rise and fall in the portal pressure is seen (fig. 11) even when the dose of lyeopodium without doubt is large enough to completely occlude the liver capillaries; and by the fact that after any dose large enough to raise the portal pressure above 15 to 20 mm. Hg., the portal pressure subsequently falls and comes to rest somewhere between 15 and 20 mm. Hg. irrespective of the size of the dose. c, The foregoing observation, on the other hand, strongly sup- ports another possible explanation, namely, that as a result of the high portal pressure a collateral circulation is established, by way of which . the portal blood can reach the systemic veins with ever increasing fa- cility. The pathways that might be developed under these circum- stances are familiar to the anatomist; they are the ones opened in man by any chronic portal obstruction. Upon the basis of our experience it can be concluded that with normal arterial pressure and splanchnic resistance, the resistance of the fully opened collaterals is such as to maintain a portal pressure of from 15 to 20 mm. Hg. Returning now to the analysis of experiment 60 (fig. 9) we believe, on the basis of the foregoing discussion, that during the rapid fall in portal presstre blood is being restored to the general circulation. It is this that accounts for the main- tenance of a constant arterial pressure despite a diminishing peripheral resist- ance. The peripheral resistance continued to diminish until, by about 3.10, it had become quite normal. At this time, though, the arterial pressure was defi- nitely below normal (84mm. Hg.). It could hardly have been otherwise; for the portal area at this time must have contained more than its normal volume of blood, and the peripheral resistance was normal. During the rest of the experi- ment, and until the animal was killed, the peripheral resistance and the arterial pressure both slowly increased, the former finally becoming somewhat above normal, the latter, quite normal. This then represents the extent of the circulatory disturbance that results from holding the portal pressure, for the most part, above 14mm. Hg. for a period of 4 hours 20 minutes by partially obstructing the portal capillaries. It must be concluded, therefore, that the amount of blood that is withheld from effective ri CIRCULATORY FAILURE DUE TO ADRENALIN OTL circulation by such distention of the portal area as is caused by a rise of the por- tal pressure to 14 mm. Hg. is not so marked but that it can be compensated al- most perfectly and indefinitely (43 hours). We further infer that this degree of portal obstruction does not result in nutritional or mechanical disturbances of such a grade as to lead to any considerable reduction in total blood volume. Even the rabbit, with its very much longer intestinal tract, may withstand perfectly similar grades of portal obstruction. This is clearly shown in experi- ment 56 (fig. 10). The injection of lycopodium here raised the portal pressure from 8 to 16 mm. Hg. The portal pressure then fell gradually to 12.5 mm. Hg. and then rose again to 13.5mm. Hg. After a transitory rise, the arterial pressure fell from 74 to 66 mm. Hg., but rose again to 72 as the portal pressure fell, and did not vary very much from that level during the rest of the period. Hr. 12:30 1:00 Fig. 10. Experiment 56. Circulatory effects of injecting lycopodium spores into the portal vein. Rabbit. Arterial pressure, — @—@—; portal pressure, —O—oO-—. a, small dose of lycopodium given; b, large dose given; c, artificial respiration necessary. The effect of very large doses of lycopodium spores may now be considered. This is illustrated by figure 11 (exp.51). A small dose was given ata. Asit evidently was not going to be sufficient for our purposes, a very large dose was given at b. Considering the effects of the larger dose only, it is seen that the rise in portal pressure again is immediate but that the fall to the plateau is very much more protracted than after smaller doses. There is a profound fall in arterial pressure (to almost 40 mm. Hg.) and a very marked peripheral constriction. The portal circulation is at its worst shortly after 1.00, for the difference between the arterial and portal pressures here amounts to only 10 mm. Hg.; presumably the pressure gradient in the splanchnic area is practically eliminated. But now the circula- tion improves for a time, presumably as a result of the opening up of byways be- tween the portal area and the systemic veins. Only by invoking some such proc- ess 1s it possible to explain the combination of a fall in portal pressure, a rise in arterial pressure, and an increase in inflow rate. By about 2.20, disregarding a passing fluctuation, conditions have become fairly stable. The arterial pres- sure is at about 50 mm. Hg., the portal pressure at 15 to 16 mm. Hg., and the inflow rate somewhat below the normal range. The jugular pressure rose throughout the course of the experiment, but the rise amounted to less thanl mm. Hg. The a2 JOSEPH ERLANGER AND HERBERT S. GASSER picture as a whole can be accounted for perfectly if it is assumed that there has occurred a reduction in the effective blood volume. Around 3.00 p.m. a change for the worse begins. The arterial pressure falls slowly; the portal pressure rises slowly, and the inflow rate steadily increases. A slow giving way of the vasomotor center, presumably under the influence of the low arterial pressure, satisfactorily explains these changes. At about 4.20 the heart gives evidence of failing, the arterial pressure and the portal pressure both Fig. 11. Experiment 51. Circulatory effects of injecting lycopodium spores into the portal vein. Dog. Arterial pressure, — @—@—; femoral inflow, - -@- -@--; portal pressure, — O— O— (lower curve on same scale as arterial pressure, upper curve on larger scale); jugular pressure, x x x. 4, injecting ly- copodium, very large dose; 6, injecting lycopodium, very large dose; c,+inflow readings transferred to other femoral; d, heart becoming irregular. 00 Hr, 10:30 11:00 11:30 12:00 Fig. 12. Experiment 57. Circulatory effects of injecting lycopodium spores into the portal vein. Rabbit. Arterial pressure, —@—@—; portal pressure, lan _ —O—O—. 4, injecting a small dose of lycopodium; b, injecting a large dose. fall rapidly, the vasomotor tone rapidly gives way, and the animal soon dies. It is worth while emphasizing that at no time during the course of this experiment could the ether be dispensed with. Whenever the mask was removed, even after the heart had become irregular (4.20), the animal soon began to struggle. Figure 8 (exp. 53) shows that a large dose of lycopodium given a dog (at a”) which already has for some hours been under the influence of moderate doses, brings about circulatory failure much more quickly than when it is given at the CIRCULATORY FAILURE DUE TO ADRENALIN 373 beginning of an experiment. The character of the response, though, is alike un- der both conditions. Thus, in this case we see the tremendous rise in portal pressure followed by a steady and comparatively rapid decline; an immediate sharp fall in arterial pressure followed by a later sharp decline when the level of 50 mm. Hg. is reached; and a further sharp vasoconstriction. A similar response is obtained from the rabbit when a large dose is given after a small dose has been acting for some time (see fig. 10, exp. 56). But to a larger dose given early in an experiment, the rabbit (fig. 12, exp. 57) seems to succumb much more rapidly than does the dog, though, as nearly as can be judged in the absence of inflow determinations, the response in the rabbit is similar in kind to that given by the dog. Asin the case of the dog (fig. 11), we see the rise in portal pressure followed by a fall to a fairly well-maintained level of about 12 to 15 mm. Hg., and a fall in arterial pressure to 50 mm. Hg. followed by a rise which then gives way to a steady fall that leads to death. 20 J = = =s | D 10 , 0 oe oe a b Hr. 11:00 1i:30 ~ 12:00 Fig. 13. Experiment 54. Circulatory efiects of injecting lyecopodium spores into the portal vein. Sick rabbit. Arterial pressure, — @— @—; portal pres- sure, —O—O—. a, moderate dose of lycopodium injected; b, respiration shal- low, heart irregular; c, respiration stopped; d, heart stopped. As might have been anticipated, it was found that the response given by sick rabbits is much more profound than that given by well animals. This is illus- trated by figure 13 (exp. 54). The dose of lycopodium suspension given was regarded as moderate. The curve, though, is quite like the one (fig. 12) just described; but it took only an hour for the circulation to fail. DISCUSSION These experiments show that an obstruction of the portal radicles in the liver that raises the portal pressure to a much higher level than it is raised by the Janeway and Jackson method of obstructing the vena cava (18), and quite as high as it is raised by the injection of adrenalin, in the dog at least, does not, even after more than 4 hours have elapsed, result in any very considerable alteration in the effectiveness of the cir- 374 JOSEPH ERLANGER AND HERBERT S. GASSER culation as evidenced by the arterial pressure and by the tone of the vasomotor center. A similar statement applies to the results obtained in the rabbit, also. Complete portal embolism in the dog immediately impairs the general circulation, as is evidenced by a low arterial pres- sure, and eventually (in 33 hours) causes the vasomotor center to fail. But even in this event the animal does not become apathetic, and therefore does not present the complete picture of shock. In the rabbit, the fatal issue develops more rapidly than in the dog, and the rabbit, if not strong, may rapidly succumb to even a moderate portal obstruction. Inasmuch as the portal obstructions we have produced by the injec- tion of lyecopodium without doubt have been quite as marked as any that could be effected by any physiological or acute pathological proc- ess (embolism and thrombosis excepted) we are forced by our results to conclude that acute portal obstruction due to the action of some physi- ological mechanism, and the consequent accumulation of blood in the splanchnic area, can scarcely be regarded as a cause of shock. Even if it should turn out that the seat of the action of adrenalin is in or beyond the hepatic capillaries, and even if it should be shown that the adrenalin obstructs the collateral, as well as the direct portal circulation, we would still regard our experimental results as sufficient to justify the statement that a portal obstruction per se cannot reasonably be regarded as the cause of the failure of the circulation following the injection of adrenalin. As a matter of fact, we have in the action of adrenalin upon the sys- temic arterioles all that is necessary to account for the failure of the circulation, namely, the consequences of an extreme and general slowing of the blood stream; though, of course, such portal obstruction as may occur after adrenalin injection will be contributory, both through me- chanical distention of vessels and through filtration of plasma, to the general slowing of blood flow due to constriction. GENERAL SUMMARY AND CONCLUSIONS 1. The injection of adrenalin for a period of 20 to 30 minutes at such a rate as to maintain a high arterial pressure invariably constricts the arteries of both the somatic and the splanchnic areas. With large doses this constriction may be maximal and outlasts the injection pe- riod, it may be, for as long as 2 hours. This continued constriction is partly due to central action. = = ee Cn CIRCULATORY FAILURE DUE TO ADRENALIN ott 2. After sufficiently large doses, the arterial pressure, barring occa- sional intercurrent phenomena, falls steadily and slowly until the ani- mal dies. ‘ 3. The jugular pressure, during or after large injections, shows no constant alteration, at least not of a kind that indicates inefficiency of the heart. 4. The heart may become irregular for a while and occasionally stops suddenly while the arterial pressure still is high. 5. The respiration after large doses often is slowed and may suddenly or gradually fail. 6. The portal pressure is increased, often markedly, during the in- jection, and may remain high subsequently; but not uncommonly it soon returns to the normal level. 7. The rise in portal pressure undoubtedly is caused by an obstruc- tion in the liver which is so marked as to back up even the small amount of blood that is entering the portal system through the strongly con- stricted splanchnic arterioles. 8. The circulation may fail suddenly through stoppage of the heart due to direct action of the adrenalin, or to the indirect action of respira- tory failure. But more often the failure of the circulation is gradual, the pressure steadily falling until the animal dies. The arterial con- striction induced by the adrenalin then lasts until the end. In such instances a reduced blood volume, either real or effective, seems to be the main factor at fault. Apathy, as well as the other signs of shock, are present. 9. Evidence is presented indicating that accumulation of blood in the portal area as a result of the increased portal-hepatic resistance is not in itself the cause of the failure of the circulation. For marked obstruction of the hepatic radicles in the liver by the injection of a suspension of lycopodium spores may not lead to the shock-like failure of the circulation that is seen after adrenalin. 10. The failure of the circulation is rather to be attributed to the ex- treme slowing of the blood flow throughout the body caused by the con- stricting action of the adrenalin on the arteries. It is concluded that the cause of the failure is the same as is operative after temporary par- tial obstruction of the vena cava or of the aorta. This conclusion is justified by the fact that the most striking lesion found in animals dying as a result of any of these three procedures is alike, and consists of tremendous engorgement of the capillaries and venules of the villi of the intestines. 376 JOSEPH ERLANGER AND HERBERT S. GASSER BIBLIOGRAPHY (1) Mepican Researcn CommitTer: Memorandum upon surgical shock, Brit. Med. Journ., 1917, 1, 381. (2) Bartietrt: Journ. Exper. Med., 1912, xv, 415. (3) ERLANGER, GESELL AND Gasser: This Journal, 1919, xlix, 90. (4) Hartman: Endocrinology, 1918, ii, 122. (5) Hoskins anp Gunnin@: This Journal, 1917, xlii, 299. (6) Hartman anp McPuepran: This Journal, 1917, xliii, 311. (7) Hoskins, GUNNING AND Berry: This Journal, 1916, xli, 518. (8) Gunnine: This Journal, 1917, xlii, 395. (9) Gruser: This Journal, 1918, xlv, 302. (10) MacWixu1am: Proc. Roy. Soc., 1902, Ixx, 109. (11) Exuiorr: Journ. Physiol., 1905, xxxii, 401. (12) BarnpripGE AND TREVAN: Journ. Physiol., 1917, li, 460. (13) Scumip: Arch. f. d. gesammt. Physiol., 1909, exxvi, 165. (14) Burton-Opirz: Quart. Journ. Exper. Physiol., 1912, v, 329. (15) Epmunps: Journ. Pharm. Exper. Therap., 1914, vi, 569. (16) ERLANGER AND GassmR: This Journal, 1919, xlix, 151. (17) Henperson, Prince anp Haaearp: Journ. Amer. Med. Assoc., 1917, Ixix, 965. (18) JANEWAY AND Jackson: Proc. Soc. Exper. Biol. and Med., 1915, xii, 193. (19) Cannon: Boston Med. Surg. Journ., 1917, elxxvi, 859. Bes PHYSIOLOGICAL STUDIES ON PLANARIA I. OxYGEN CONSUMPTION IN RELATION TO FEEDING AND STARVATION L. H. HYMAN From the Hull Zoélogical Laboratory, University of Chicago Received for publication June 3, 1919 For a number of years the physiology of Planaria and other lower invertebrates has been extensively investigated in this laboratory. As a result of these investigations certain fundamental conceptions have been reached. These conceptions are in part concerned with the metabolic gradients of organisms and their relation to the phe- nomena of polarity, symmetry, individuation, regeneration, reproduc- tion and development; and in part with the relation between metabolic rate and regeneration, age, starvation and other physiological con- ditions. These conclusions and the evidence from which they are derived have been presented by Professor Child in numerous papers and in his two books Senescence and Rejuvenescence and Individuality in Organisms. In reaching these conceptions, various methods have been employed. Two of these are referred to in this paper and require explanation. One of them is called by us in the direct susceptibility method and consists in observing the time of death of organisms or parts of organ- isms in lethal concentrations of certain substances or under lethal conditions such as lack of oxygen, extreme temperatures, etc. A great variety of substances has been employed for this purpose, including cyanides, acids, bases, salts, anesthetics and dyes; all of them yield practically identical results, but we have found that cyanides constitute the most delicate and precise indicators of susceptibility differences. We believe that the time of death in such solutions or under such conditions is a direct measure of the metabolic rate of the protoplasm so tested. The chief grounds for this belief are: all conditions which are known to increase the general metabolic rate also increase the susceptibility to these solutions; in the case of the cyanides at least there is a large body of evidence, which I have reviewed in a recent k 377 THE AMERICAN JOURNAL OF PHYSIOLOGY, VOL. 49, NO. 3 378 L. H. HYMAN paper (1), which demonstrates that cyanides depress metabolic rate, and further we have recently shown (1), (2), that potassium cyanide decreases to a very marked degree both the carbon dioxide production and the oxygen consumption in Planaria; and finally the susceptibility data check completely with the results obtained by the second method referred to. This method consists in the determination of the carbon dioxide production of organisms or parts of organisms either by means of the Tashiro biometer or by means of an indicator, chiefly phenol- sulphonephthalein. The carbon dioxide production furnishes the same conclusions regarding metabolic rates as does the susceptibility method, wherever comparable conditions are present. In consideration of a misunderstanding which has arisen among other workers regarding the susceptibility method, it becomes neces- sary to emphasize the fact that the method in general measures only the susceptibility of the superficial structures of the body, since as a rule it is these only whose time of death can be accurately observed. Hence the time of death in these toxic solutions is, strictly speaking, a measure of the metabolic rate of the body wall and nervous system only and not of the total metabolic rate. It becomes a measure of the total metabolic rate only when comparable internal conditions exist. Hence when these internal conditions are altered as by introducing food into the intestine, the susceptibility of the surface will obviously not measure the metabolic rate of the intestine nor the total metabolic rate, since this is the sum of the activity of all parts of the body. Therefore the objections of Lund (3) to the susceptibility method on the grounds that in Paramecium the susceptibility is increased by short periods of starvation but the total oxygen consumption and car- bon dioxide production are decreased are without basis and without point. In Protozoa obviously only the condition of the ectoplasm can be determined by the susceptibility method since as soon as the ectoplasm dies and disintegrates, the entoplasm scatters and can no longer be observed. In the cases of other organisms, however, it is sometimes possible to observe the time of death of both the intestine and the body wall separately and therefore to draw a correct conclusion regarding the total metabolism. The expression ‘‘metabolie rate’? seems to require definition. The word metabolism is generally taken to signify the sum of all the energy- producing and substance-producing processes occurring in the body. Each such process may, of course, have a rate of its own, and in. order to find out the total metabolic rate at any one time it would be OXYGEN CONSUMPTION IN FEEDING AND STARVATION 379 necessary for strict accuracy to determine the rate of each process separately. This procedure is practically impossible and probably unnecessary, since it happens that in the animal body the majority of such processes are energy-consuming, that is, they use up oxygen and give off carbon-dioxide. It is therefore generally adequate to measure the rate of respiratory exchange in organisms in order to obtain some idea of the total metabolism. In the higher organ- isms, other methods are also at hand, as urine analysis, blood analysis, heat production, ete., which, however, cannot be applied to the lower forms. I wish to point out further that the rate of oxygen con- sumption and carbon-dioxide production are adequate measures of the rates of processes not in themselves essentially oxygen-consuming, such as the contraction of muscles; and that they furnish information about apparently unrelated conditions such as the irritability and conductivity of nerves. For these reasons we use the term metabolic rate instead of the more specific expression respiratory exchange, since we believe such respiratory rate to be an index of many other metabolic and physiological conditions besides oxidation. We also believe that the susceptibility method measures other metabolic conditions besides the rate of oxidation. We use the expression metabolic rate to indicate the rate of the large general chemical proc- esses occurring in the body and not with reference to conditions specific to one organ or part nor with reference to special conditions. Thus the rate of the heart beat is an index to general physiological states such as age, sex, nutrition, etc., but obviously it would be foolish to attempt to draw conclusions regarding these states from the rate of the heart beat under special conditions where it had been altered, as after exercise. It is in precisely the same sense that we speak of metabolic rate, in reference to long-lasting and general processes, common to all of the cells of the body. As previously stated, in our work on the physiology of the lower forms we have employed chiefly the method of differential suscep- tibility and the measurement of carbon-dioxide production. The present series of papers is concerned with the rate of oxygen con- sumption under various physiological conditions and therefore con- stitutes a check upon the results obtained by the other methods. ~ The work has unfortunately been greatly hampered and delayed by the accidental loss in the spring of 1918 of our entire stock of Planaria, numbering many thousands. This has necessitated the use of some- what smaller lots of worms than would ordinarily have been the case. 380 L. H. HYMAN The present paper reports the results of my experiments on the rate of oxygen consumption of Planaria in feeding and starvation; experiments on oxygen consumption with respect to age and regener- ation are also completed. It is gratifying to state that these results confirm the conclusions reached by the other methods. METHOD These experiments were performed upon Planaria dorotocephala and Planaria velata, two common species of flatworm, both of which have been used as the chief experimental material in the investigations mentioned in the opening paragraph. The method was the same as that described in a recent paper (1) except that, owing to the smaller stocks available, smaller receptacles and. samples were employed. Briefly each lot of worms to be tested was placed in a 500 ce. Erlen- meyer flask filled air-tight with water, and allowed to respire in this flask at constant temperature for the desired length of time. A sample of the water was then withdrawn and analyzed for oxygen content by Winkler’s method, and the difference between the oxygen content of this sample and a control sample similarly treated gave the oxygen consumption of the worms. In most cases where time and circumstances permitted, each test was repeated, so that two separate determinations of the oxygen consumption of a given lot of worms were obtained. In order to compare the rates of oxygen consumption of the same lot of worms at different intervals it is necessary to know their weight. The oxygen consumption of these organisms is directly proportional to their weight, other factors bemmg equal. This appears clearly in the experimental tables, and is in fact so axiomatic as to require no further discussion. The following method of weighing the worms was found most suitable. The animals were collected in a funnel of filter paper, being washed down to the point of the funnel by a pipette. After the water had drained through, the filter paper was opened out and spread flat on top of two or three layers of moist filter paper until all excess water had been absorbed, small pieces of dry filter paper being also placed under the mass of worms to aid the process. The worms were then scraped up with a dry scalpel blade into a small glass receptacle, previously balanced on the scales, and rapidly weighed. Weighings were made to the third place only. This method has been found more rapid and accurate than procedures in which the worms are bt OXYGEN CONSUMPTION IN FEEDING AND STARVATION 381 weighed in water, since it is almost impossible to avoid adding or withdrawing water. Usually some worms are injured through drying but as the weighings were nearly always made at the conclusion of the experiment, this was not of any consequence.. If, however, it was necessary to weigh the worms before the experiment, the injured worms were collected and weighed separately and this weight then subtracted from the first weight. The injured worms were always discarded. Tests have shown that this method of weighing is sufficiently accurate for the purpose at hand. In these tests the same lot of worms was returned to water, re-collected and weighed again. Such duplicate weighings are not, however, strictly comparable, since the worms. lose weight after weighing owing to the secretion of mucus due to the stimulation of drying. If this mucus is removed, the weight of the worms will be less than it was at the first trial; if retained, it may be more, as the mucus absorbs water. A fair idea of the loss due to the weight of the mucus can be obtained by drying it on filter paper and weighing it separately. The following are duplicate weighings of the same lot of worms: 0.192, 0.186 gram (mucus retained); 0.527, 0.532 (mucus retained); 0.458, 0.451 (mucus removed); 0.763, 0.746 (mucus removed, separate weight of the dried mucus, 0.014); 0.817, 0.802 (mucus removed, separate weight of the dried mucus, 0.014). Eight lots of Planaria dorotocephala and three lots of Planaria velata were used in the experiments. Each lot, consisting of individuals of approximately the same size and condition, was selected from one of the general laboratory stocks. The oxygen consumption of each lot was then determined at various intervals after feeding and through a period of starvation, the lot being weighed after each such determi- nation. The water was changed at intervals and the lots examined from time to time and all individuals noticeably larger or smaller than the average, all injured individuals and all posterior products of fission removed and discarded. When Planaria is placed in a clean receptacle, it is likely to undergo fission. This can be obviated to some extent by avoiding the use of clean dishes and placing the worms only in dishes previously occupied by worms. However, it is necessary to examine the dishes at intervals and pick out the products of fission. - In the present experiments, all of the posterior products of fission have been removed and the anterior ones have been retained only when they constituted nearly the whole of the original worm. Thus these experiments deal only with whole worms of small size or anterior zooids. As shown by Child’s work (4), the posterior zodids behave 382 L. H. HYMAN somewhat differently during starvation than whole worms or anterior zooids. As starving planarians will eat each other if possible, it is advisable to employ large receptacles for the starving stocks and to remove all individuals which vary much in size from the average of the stock. As starvation proceeds, the heads of the worms, especially if they were rather small individuals at the start, are likely to dis- integrate, and new heads are then regenerated. Such individuals were removed during the early stages of the experiments but not at the end, as many of the individuals in some of the stocks were in this condition. Since movement increases both the oxygen consumption and carbon dioxide production, movement is a disturbing factor in any experi- ments on the rate of respiratory exchange. In most of our experiments on Planaria, we remove the heads of the individuals to be tested several hours before the test, since decapitated worms remain perfectly quiet. This procedure was not thought advisable in the present experiments since the subsequent regeneration of the heads would introduce an additional factor. Hence it was necessary to observe carefully the degree of movement. If the worms are placed in the experimental flask several hours before the test, and if the flask is darkened during the test, movement can be largely eliminated. Movement is most likely to occur during the middle of the starvation period, recently fed worms or greatly starved worms being generaliy inclined to in- activity. Hence the figures obtained during the middle of the star- vation period are probably slightly too high on account of movement. At the end of the starvation period at the last test made, in order to eliminate this factor completely, the heads were cut off, unless they had previously disintegrated as a consequence of starvation. Hence the final figures on the rate of oxygen consumption after prolonged starvation are entirely free from this difficulty. Further details regarding the worms are given in the following records of the experiments. EXPERIMENTAL RESULTS WITH PLANARIA DOROTOCEPHALA Planaria dorotocephala is the species which has been employed in most of the investigations carried out by Professor Child and his students. - Large stocks of this worm are kept constantly in the laboratory and fed three times a week on liver. From these general stocks eight lots, designated as A, B, F, G, H, K, M and N were selected OXYGEN CONSUMPTION IN FEEDING AND STARVATION 383 for the present experiments. The members of each lot were of approxi- mately equal size and had been kept under the same conditions for some time preceding the experiments. Details regarding the make- up of each lot and the data obtained upon them are given in the fol- lowing descriptions and accompanying tables. Six of the eight lots were fed and the effect of feeding as well as that of starvation on the oxygen consumption determined. # In the tables, the first column gives the length of time since feed- ing. The second column gives the actual figures of the oxygen consumption in a given period of time of the lot of worms on the day designated in the first column. In most cases two figures, the results of two separate determinations, are presented. The third column gives the weight of the lot of worms just after testing. The last column in each table is a calculation of the average oxygen consumed in cubic centimeters in two hours by 0.5 gram of Planaria. This cal- culation to a given weight and time is, of course, necessary in order to compare the rate of oxygen consumption at different periods of starvation. The time period and weight chosen for this calculation are, of course, purely arbitrary, selected as most nearly corresponding with the weights and time periods actually used in the experiments. A word may be needed in explanation of the recorded weights. In the case of lots A, B, F, G and H, not all of the individuals in each lot were used each time in the early part of the experiments, a cir- cumstance which accounts for the variability in weight. In lots K, M and N, the entire lot was used at each test, and the recorded weights therefore illustrate the loss of weight of these lots during starvation, with one increase due to feeding. I was somewhat at a loss to know how to regard the increase in weight resulting from in- gestion of food. I finally decided that such increase should not be calculated in the results since this additional weight from the ingested food can hardly be regarded as respiring protoplasm, at least not within the first twenty-four hours after feeding. Hence in the feeding experiments the worms were weighed just before feeding, and this weight was used for calculating the rate of oxygen consumption after feeding. The temperature of all experiments was 22 + 0.5°C. Record of lot A (table 1). Lot A consisted of worms about 10 mm. long selected from a stock which had been in the laboratory for four or five months (the exact date of collection was not known). They were last fed on March 3, 1919. On March 8, five days after feeding, 384 L. H. HYMAN the average oxygen consumption of 0.5 gram in two hours was 0.30 ec.; on March 15, twelve days after feeding, it was 0.26; on March 29, after twenty-six days of starvation it was 0.36; and on April 29, after about two months’ starvation, 1.50 cc. of oxygen was consumed. At this time when the experiment was concluded, the size and number of the worms was greatly reduced and most of them had lost their heads so that movement could not%have played any role in the final result. TABLE 1 Record of lot A CALCULATION, TIME SINCE FEEDING OXYGEN CONSUMED IN TEST WEIGHT casei peels se TWO HOURS days ce. grams cc. 5 0.30 in 2 hours 0.464 0.30 0.26 in 2 hours 12 0.28 in 2 hours 0.499 0.26 0.24 in 2 hours 26 0.22 in 2 hours 0.302 0.36 5Y6 0.15 in 3 hours 0.16 in 3 hours 0.034 150 TABLE 2 Record of lot B CALCULATION, TIME SINCE FEEDING OXYGEN CONSUMED IN TEST WEIGHT etre pape Se TWO HOURS days ce. grams ce. 5 0.46 in 2 hours 0.712 0.31 0.42 in 2 hours 12 0.26 in 2 hours 0.566 0.23 0.28 in 2 hours 26 0.23 in 2 hours 0.464 0.24 56 0.13 in 2 hours 0.147 0.47 0.15 in 2 hours Record of lot B (table 2). Lot B was selected from a stock collected in February, 1919. They were slightly larger than the worms in the preceding stock, about 12 to 13 mm. long. The worms were last fed on March 5. On March 10, five days after feeding, the oxygen consumed in two hours by 0.5 gram was 0.31 cc.; on March 17, twelve days without food, it was 0.26 ec.; on March 31, after twenty-six days without food, it was 0.24; and at the end of the experiment, May | OXYGEN CONSUMPTION IN FEEDING AND STARVATION 385 1, after nearly two months of starvation, it was 0.47. The worms were much reduced in size but had retained their heads. These were cut off several hours before the final test. Record of lot F (table 3). This lot of worms was taken from a mixed stock which had been used for various other purposes. Worms in this stock had been collected during the fall and winter. The members of this lot were last fed'on March 10. They were 12 to 15 mm. in length. On March 18, eight days after feeding, they consumed 0.25 ee. of oxygen in two hours as calculated for 0.5 gram weight. They TABLE 3 Record of lot F CALCULATION, 2 OXYGEN CONSUMED TIME SINCE FEEDING OXYGEN CONSUMED IN TEST WEIGHT By 0.5 GRAM IN TWO HOURS cc. grams cc. 8 days 0.17 in 13 hour 0.17 in 14 hour 0.444 0.25 Fed immediately after above determination 1 to 3 hours 0.34 in 14 hour 0.444* 0.50 3 to 5 hours 0.28 in 14 hour 0.444* 0.42 2 days 0.18 in 14 hour 0.486 : 0.25 0.19 in 13 hour 3 7 days 0.21 in 2 hours 0.413 0.22 0.17 in 2 hours 21 days 0.12 in 2 hours 0.214 0.28 48 days 0.17 in 3 hourst 0.075 0.80 0.19 in 3 hours ; * Weight taken before feeding, see text. + Figures obtained on combined lots, F, G and H. were then fed on liver and their oxygen consumption tested one to three hours after feeding. It was now 0.50 cc. Three to five hours after feeding it had fallen to 0.42 cc. It must be noted that the weight of these worms was taken before feeding and they were not weighed again after feeding as it was considered that the increased weight resulting from the intake of food could not properly be calculated with respiring protoplasm. It was therefore considered fairer to omit the increase in weight following feeding. On March 20, two days after feeding, the oxygen consumption had fallen to 0.25 ec.; on March 25, a week since feeding, it was 0.22; on April 8, three weeks of star- 386 L. H. HYMAN vation, it was 0.28; and on May 5, when the experiment was con- cluded, after a fast of seven weeks, it was 0.80. The condition of the worms was similar to that in ‘the preceding stocks. The number remaining was so few that it was necessary to combine those from lots G and H with those of lot F for the final determination on May 5. These three lots came from the same stock and had been treated in an identical manner throughout the course of the experiment. Record of lot G (table 4). The worms in this lot came from the same stock as those of lot F, were of the same size and were handled TABLE 4 Record of lot G CALCULATION, TIME SINCE FEEDING OXYGEN CONSUMED IN TEST WEIGHT pet oe paler 0.5 GRAM cc. grams ce. 8 days 0.17 in 14 hour 0.494 0.23 0.18 in 14 hour Fed immediately after above determination 1 to 3 hours 0.29 in 13 hour 0.466* 0.40 3 to 5 hours 0.26 in 13 hour 0.466* 0.37 2 days - 0.13 in 14 hour 0.423 0.26 0.20 in 14 hour 7 days 0.17 in 2 hours 0.344 0.24 0.16 in 2 hours 21 days 0.11 in 2 hours 0.176 0.31 48 days 0.17 in 3 hourst 0.075 0.80 0.19 in 3 hours * Weight taken before feeding, see text. + Figures obtained on combined lots, F, G and H. throughout in the same way. On March 18, eight days since the last feeding, they consumed 0.23 cc. of oxygen as calculated for 0.5 gram weight for two hours. They were then fed on liver, and one to three hours after feeding they consumed 0.40 cc.; three to five hours after feeding, 0.37 ec. On March 20, two days later, their oxygen con- sumption was 0.26; on March 25, one week after feeding, it was 0.24; on April 8, three weeks without food, it was 0.31; and on May 5, seven weeks without food, it was 0.80. As noted for lot F, this final figure was obtained on the combined individuals from lots F, G and H. OXYGEN CONSUMPTION IN FEEDING AND STARVATION 387 Record of lot H (table 5). This lot was the same as to origin, size and handling as the preceding lots F and G. On March 18, eight days since the last feeding, the oxygen consumption was 0.24 cc. in two hours per 0.5 gram weight. The worms were then fed, and during the first to third hour after feeding they consumed 0.44 ec. of oxygen; during the third to the fifth hour after feeding, 0.42 cc. Two days later, their oxygen consumption had fallen to 0.33 cc.; a week after feeding, it was 0.24; after three weeks without food, it was 0.31; and after seven weeks’ starvation, it was 0.80. The three lots F, Gand H TABLE 5 Record of lot H CALCULATION, TIME SINCE FEEDING OXYGEN CONSUMED IN TEST WEIGHT peters teet 0.5 GRAM ce. grams cc. 8 days 0.16 in 14 hour 0.440 0.24 0.16 in 14 hour Fed immediately after above determination 1 to 3 hours 0.28 in 14 hour 0.421* 0.44 3 to 5 hours 0.27 in 13 hour 0.421* 0.42 2 days 0.18 in 13 hour 0.387 , 0.33 0.21 in 14 hour 7 days 0.18 in 2 hours 0.346 0.24 0.16 in 2 hours 21 days 0.12 in 2 hours 0.192 0.31 48 days 0.17 in 3 hourst 0.075 0.80 0.19 in 3 hours * Weight taken before feeding, see text. + Figures obtained on combined lots, F, G and H. were, as can be readily seen, run simultaneously and were always under the same conditions. At the end of the starvation experiment they were greatly reduced in size and most of them had lost their heads, thus eliminating movement as a factor in the final determination. Record of lot K (table 6). Lots K, M and N were three lots selected from the same stock and run in all respects under the same conditions. These three lots were tested with especial care, and the data presented for them are hence possibly more exact than the data for the five preceding lots. They were selected from a new stock, collected on March 11, 1919. They were last fed on March 24. The worms of 388 L. H. HYMAN these lots were larger than in the preceding cases, 15 to 18 mm. long. In consequence of this larger size, they were not reduced so much at the end of the experiment, and all had retained their heads throughout the period of starvation. The possible disturbing factor of regener- ation of the head is therefore eliminated in the case of these three lots. These worms were also so active at the conclusion of the experiment that it was necessary to decapitate them before testing their rate of oxygen consumption. In these three lots then movement has been completely eliminated as a factor in the final results. In short, the TABLE 6 Record of lot K CALCULATION, TIME SINCE* FEEDING OXYGEN CONSUMED IN TEST WEIGHT pets pela 0.5 GRAM cc. grams cc. 4 days 0.23 in 14 hour 0.589 0.25 Fed immediately after above determination 2 to 4 hours 0.46 in 14 hour 0.579* 0.52 7 to 83 hours 0.48 in 13 hour 0.579* 0.54 24 hours 0.30 in 14 hour 0.579* 0.32 3 days 0.32 in 2 hours 0.628 0.25 7 days 0.27 in 2 hours 0.548 0.24 21 days 0.21 in 14 houry 0.325 0.38 0.16 in 14 hour 48 days 0.11 in 2 hours 0.112 0.53 0.13 in 2 hours * Weight taken before feeding, see text. + Considerable movement during this determination. data for these three lots seem to me to be absolutely dependable and to be free from all possible sources of error. The entire stock was used in each case for each determination, and hence the weights given are a fair picture of the loss of weight of Planaria during starvation. Of course a few individuals were discarded from time to time on account of injury. Fission, however, was practically absent in these lots. The oxygen consumption of lot K on March 28, four days after feeding was 0.25, calculated as before for two hour periods and for 0.5 gram of weight. The worms were then fed and the oxygen con- sumption two to three and a half hours after feeding was 0.52; seven OXYGEN CONSUMPTION IN FEEDING AND STARVATION 389 to eight and a half hours after feeding it was 0.54. On the next day, twenty-three to twenty-four hours after feeding, it was 0.32. On March 31, about three days after feeding, it was 0.25; on April 4, a week without food, it was 0.24; April 18, three weeks without food, it was 0.38; and at the conclusion of the experiment, on May 15, after seven weeks’ starvation, it was 0.53. It should be noted that the worms were rather active during the determination of April 18, and hence the figures obtained upon this date are slightly too great, partic- ularly the first of the two successive determinations. During the TABLE 7 Record of lot M CALCULATION, OXYGEN CONSUMED TIME SINCE FEEDING OXYGEN CONSUMED IN TEST WEIGHT IN TWO HOURS BY 0.5 GRAM ' ce. grams CC. 4 days 0.29 in 14 hour 0.761 0.25 Fed immediately after above determination 2 to 4 hours 0.58 in 14 hour 0.747* 0.51 7 to 8} hours 0.54 in 14 hour 0.747* 0.48 24 hours 0.37 in 13 hour 0.747* 0.33 3 days 0.43 in 2 hours 0.779 0.28 7 days 0.32 in 2 hours 0.671 0.23 21 days 0.23 in 14 houry 0.424 0.31 0.17 in 14 hour 48 days 0.13 in2 hours’ - 0.159 0.45 0.16 in 2 hours *Weight taken before feeding, see text. , tT Considerable movement during this determination. second analysis they were for the most part inactive and hence this figure is more nearly correct. As already stated the heads of the worms were cut off for the final determination so that movement was completely eliminated. Record of lot M (table 7). All the remarks made with reference to lot K apply to this lot also. Four days after the last feeding, lot M consumed 0.25 ee. of oxygen; on the same day, two to three and one- half hours after feeding, this figure rose to 0.51 ec.; and seven to eight and one-half hours after feeding, it had fallen slightly to 0.48. The next day it was 0.33 cc.; on the third day after feeding, 0.28; after a 390 L. H. HYMAN week without food, 0.23; after three weeks, 0.31; and after seven weeks’ starvation, 0.45. Record of lot N (table 8). This lot is similar in all respects to the two preceding lots. These worms consumed on the fourth day after feeding 0.23 ec. of oxygen per 0.5 gram weight in two hours; on the same day shortly after feeding, the oxygen consumption rose to 0.51, and fell a few hours later to 0.49. The next day it was 0.31; the third day after feeding, 0.27; a week after feeding, 0.22; after three weeks without food, 0.28; and after seven weeks without food, 0.56. TABLE 8 Record of lot N CALCULATION, OXYGEN CONSUMED TIME SINCE FEEDING OXYGEN CONSUMED IN TEST WEIGHT IN TWO HOURS BY 0.5 GRAM cc. grams ce. 4 days 0.27 in 13 hour 0.769 0.23 Fed immediately after above determination 2to4hours | 0.58 in 13 hour 0.758* 0.51 7 to 84 hours 0.56 in 13 hour 0.758* 0.49 24 hours 0.36 in 14 hour 0.758* 0.31 3 days 0.45 in 2 hours 0.832 0.27 7 days 0.32 in 2 hours 0.706 0.22 21 days 0.19 in 14 hour 0.446 0.28 0.19 in 13 hour 48 days 0.14 in 14 hour 0.125 0.56 0.14 in 14 hour * Weight taken before feeding, see text. EXPERIMENTS WITH PLANARIA VELATA Planaria velata is a turbellarian flatworm found in temporary pools in the spring in the Chicago region. Associated with the peculiar conditions of life which exist in temporary pools, the life cycle of this. animal is exceptionally interesting. It has been investigated by Child, to whose paper on the subject the reader is referred (5). The animal emerges from cysts in the spring when the temporary ponds fill with water, grows rapidly and soon attains adult size. It then ceases to feed and posterior portions of its body drop off, secrete a mucous cyst about themselves, and pass into a quiescent state within this cyst. OXYGEN CONSUMPTION IN FEEDING AND STARVATION 391 This process continues until the entire worm has formed a series of cysts. After about four weeks, in case the pond still contains water, the worms emerge from the cysts, but they are now completely re- generated whole worms of small size. This cycle is repeated until the pond dries up, whereupon the cysts remain quiescent until the following spring. I performed three experiments with this species. In each case the experiment was interrupted by the formation of cysts. The young worms which emerge from the cysts are of course in a state of extreme starvation. As, however, not all of them emerge at once, it was necessary to feed those which emerged first in order to keep them alive until a number of individuals sufficient for a determination of their oxygen consumption had appeared. The young starved worms were therefore fed two or three times at long intervals. Since this feeding was entirely inadequate to bring about growth, it is certain ’ that at the time of testing the young worms were still in a state of extreme starvation, and that their oxygen consumption therefore truly represents starvation metabolism. In addition it must be noted that these worms have also undergone regeneration. Now as I shall show in the second paper of this series, regeneration also greatly in- creases the rate of oxygen consumption. Hence, in these experiments with Planaria velata, the end result is a combination of the effects of both starvation and regeneration on the metabolic rate. It is not in this particular case possible to separate these two factors, although one can prevent this species from undergoing encystment by beginning to starve the worms before they have attained adult size. This I attempted to do but evidently growth had already progressed too far when I began the experiments and all of the worms encysted. Record of lot C (table 9). This lot of Planaria velata was taken from a collection of March 7, 1919. They were fed once after being received in the laboratory, on March 10. The individuals selected for the experiment were 10 to 12 mm. long. On March 13, three days after feeding, they consumed 0.31 ce. of oxygen in two hours per 0.5 gram weight. On the same day, two to three and one-half hours after feeding, the oxygen consumption was 0.43. It should be noted that only a small proportion of the lot fed, as they were evidently already on the verge of encystment. On March 15, two days after feeding, the oxygen consumption was 0.32; on March 20, a week without food, it was 0.29. The worms now rapidly encysted and in a week or two the dishes were a mass of small round cysts. Late in 392 L. H. HYMAN TABLE 9 Record of lot C CALCULATION, TIME SINCE FEEDING OXYGEN CONSUMED IN TEST WEIGHT aee oe SO 0.5 GRAM ce. grams cc. 3 days 0.32 in 13 hour 0.745 0.31 0.42 in 14 hour Fed immediately after above determination 2 to 34 hours 0.46 in 14 hour 0.707* 0.43 2 days 0.28 in 14 hour 0.602 0.32 0.30 in 14 hour 7 days 0.19 in 14 hour 0.428 0.29 Worms encysted and emerged as young worms, see text 75 days 0.10 in 3 hours 0.058 0.68 0.14 in 3 hours TABLE 10 Record of lot D CALCULATION, TIME SINCE FEEDING OXYGEN CONSUMED IN TEST WEIGHT eat Coheataet 0.5 GRAM cc. ‘a grams cc. 3 days 0.44 in 13 hour “0.774 0.35 0.39 in. 13 hour Fed immediately after above determination 2 to 34 hours 0.50 in 13 hour 0.754% 0.49 2 days 0.37 in 14 hour 0.648 0.38 0.37 in 13 hour R 7 days 0.22 in 13 hour 0.525 0.27 Worms encysted and emerged as young worms, see text 70 days 0.19 in 3 hours 0.140 0.70 0.21 in 3 hours * Weight taken before feeding, see text. OXYGEN CONSUMPTION IN FEEDING AND STARVATION 393 April and throughout May, the young worms were emerging. They were picked out on May 3, and fed at that time; then again on May 10, and fed; and again on May 21. On May 26, those which had emerged since were added to the lot of young worms and at this time the heads of all were cut off to prevent movement. On May 27, the final test of the rate of oxygen consumption was made. It should be noted therefore that lot C at that time was made up of young worms, some of which had been fed three times, some twice, some once, and some not at all. As already noted the feedings were at such long intervals that the worms were in a state of starvation. The oxygen consump- tion on May 27 was 0.68. Record of lot D (table 10). This lot of worms was identical in make- up and kept under the same conditions as the preceding lot. On March 13, three days after feeding, the oxygen consumption was 0.35 cc.; on the same day a few hours after feeding (most of the worms refused to feed), it was 0.49. Two days later, it was 0.38; and after a week without food, it was 0.27. Encystment now ensued as related in the preceding case. The emerged worms were fed on May 3 and May 10 and tested on May 22, so that the lot finally tested contained some worms which had been fed once, some twice and some which had not received any food. The oxygen consumption on May 22 was 0.70 ec. The heads were not removed but the worms certainly were no more active than in the earlier tests on this lot, so that the results are dependable. Record of lot E (table 11). This lot is identical with lots C and D. On March 13, three days after feeding, the oxygen consumption was 0.34; on the same day, a few hours after feeding, it rose to 0.53. More of the individuals in this case took food than in the case of the two preceding lots. Two days later, the oxygen consumption had fallen to 0.35 cc.; and a week after feeding it was down to 0.21. After emergence from the cysts, the young worms were fed on May 3 and May 10, and tested on May 22, some of the lot at the time of the test having therefore fed twice, others once, and others not at all. On this day, the oxygen consumption was 1.05. On May 26, all worms which had emerged in lots C, D and E since May 22 were collected into one lot and their heads removed. No - members of this lot had been fed, and they had therefore been without food for seventy-five days. Their rate of oxygen consumption was tested on May 27. They consumed 0.16 and 0.17 cc. of oxygen in two tests, each lasting three hours. They weighed 0.067. The THE AMERICAN JOURNAL OF PHYSIOLOGY, VOL. 49, NO. 3 394 L. H. HYMAN oxygen consumption as ‘calculated for two hours and for 0.5 gram weight was 0.80. In this experiment, then, movement had been completely eliminated by decapitation, and none of the worms had received food. The rate of oxygen consumption of such emerged starved worms was more than twice as high as that of the same worms a few days after feeding. Both regeneration and starvation are involved in this increase, as already noted. TABLE 11 Record of lot E CALCULATION, OXYGEN CONSUMED TIME SINCE FEEDING OXYGEN CONSUMED IN TEST WEIGHT IN TWO HOURS BY 0.5 GRAM cc. grams cc. 3 days 0.31 in 13 hour 0.593 0.34 Fed immediately after above determination 2 to 33 hours 0.47 in 13 hour 0.581* 0.53 2 days 0.29 in 13 hour 0.494 0.35 0.24 in 14 hour 7 days 0.12 in 13 hour 0.374 0.21 Worms encysted and emerged as young worms, see text 0.18 in 3 hours 0.60 1.05 0.20 in 3 hours 70 days * Weight taken before feeding, see text. CONCLUSIONS AND DISCUSSION The data obtained from eleven different lots of Planaria, belonging to two species, are in complete agreement with each other and serve to demonstrate the following facts regarding the oxygen consumption of Planaria during feeding and starvation. 1. The oxygen consumption is increased after feeding. The amount of this increase depends directly upon the number of individuals which take in food. Thus in the case of lots K, M and N, presented in tables 6, 7 and 8, where practically all of the individuals fed, the increase is more than 100 per cent, while in lots F, G and H, in which some individuals did not feed, the increase ranges from 80 to 100 per cent, and in lots C and D, where the majority of the individuals OXYGEN CONSUMPTION IN FEEDING AND STARVATION 395 refused to feed, the increase is only 40 per cent. In lot E, worms comparable in every way to those of lots C and D, more of the worms were observed to apply themselves to the meat and a correspondingly greater increase, about 60 per cent, in rate of oxygen consumption was found. 2. This increase in the rate of oxygen consumption due to feeding begins to fall within a relatively short period of time after feeding. A slight decrease is noticeable seven to eight hours after feeding, and twenty-four hours after feeding the rate has fallen off very markedly. The rate continues to fall more slowly from this time on and reaches a minimum value one to two weeks after the last feeding. 3. After the rate of oxygen consumption has reached a certain minimum value, it begins to rise. This rise is distinctly noticeable three weeks after feeding. 4. The oxygen consumption continued to rise as long as the experi- ments were continued. After seven to eight weeks without food, the oxygen consumption is two to five times as great as it is in the same worms several days after the last feeding. 5. Starvation is therefore a means of increasing the rate of oxygen consumption of Planaria. After a long period of starvation the or- ganism has a metabolic rate like that of young worms and resembles them in shape and proportions, color, rapidity of movement and in general reactions and behavior. Child has shown (4) that the carbon- dioxide production of young worms is invariably greater than that of old worms per unit weight. I have recently found (results to be published shortly) that similarly the oxygen consumption of young worms is invariably higher than that of old worms, per unit weight, both being in a condition of adequate nutrition. The difference be- tween fed young and old worms is not so great as that between fed and starved worms. Starved worms are therefore metabolically like young worms, when both are compared with old fed worms. These conclusions merit further discussion, with reference to experi- ments on Planaria by other methods and experiments on other forms. The effect of feeding and starvation on Planaria dorotocephala and Planaria velata has already been studied by Child by means of the susceptibility method and through carbon-dioxide production (4), (5), (6), (7). A significant difference exists between the results ob- tained by these two methods. The susceptibility continually increases during the period of starvation and is not increased by feeding, while both the carbon-dioxide production and the oxygen consumption 396 L. H. HYMAN are increased by feeding, decrease during the earlier stages of star- vation, and increase only in the later stages of starvation. As already emphasized in the introductory remarks, susceptibility concerns chiefly the metabolic condition of the superficial structures of the body. The metabolic rate of these structures is then not increased by feeding but increases throughout the period of starvation. On the other hand, the susceptibility of the intestine, which can be ob- served separately in Planaria, is increased by feeding, falls after feeding, and rises again in the later stages of starvation. The susceptibility of the intestine therefore runs parallel to the total metabolism as measured by both carbon dioxide production and oxygen consumption. It is therefore certain that the increase in the rate of respiratory ex- change seen after feeding in Planaria is due entirely to the increased activity of the digestive apparatus and the subsequent decrease in total metabolism during the early stages of starvation is due to the decreased activity of the digestive tract. The data at hand permit us to draw certain conclusions as to the factors involved in the increase of metabolic rate after feeding. I have already mentioned that the effect of feeding on total metabolism decreases rapidly so that within twenty-four hours after a single feeding, the rate had fallen to a marked extent. Now it is certainly impossible for Planaria to digest a meal completely in this short length of time. The intestine of Planaria remains filled with food undergoing digestion certainly for as long as a day after feeding and probably much longer. If Planaria is fed on blood clot, the corpuscles can still be recognized within the intestine on the following day. If these worms are fed at intervals of two days, only a portion of them will take food on each occasion. Hence it is fairly certain that in Planaria the rise in rate of oxygen consumption after feeding cannot be attributed to assimilation or similar anabolic processes, since such processes would be going on even more rapidly twenty-four hours after feeding than a few hours after feed- ing; yet by the next day the oxygen consumption has fallen markedly. Further any increase in assimilative processes ought to be detectable in other parts of the body also but the susceptibility method demon- strates that the metabolic rise following feeding involves the intestine only. One may therefore conclude that in Planaria the increase in metabolic rate following feeding is attributable to the activity of the intestine, including probably such processes as the secretion of digestive enzymes by the entoderm, amoeboid movements of the entoderm cells, and absorption of food through the entoderm, all processes which OXYGEN CONSUMPTION IN FEEDING AND STARVATION 397 are known to involve an increased rate of respiratory exchange. It is probable, however, that all of these activities combined are not adequate to account for the increase observed. One must therefore postulate a direct stimulation of the entoderm cells by the food or its products, causing an increase in the intrinsic metabolic rate of these cells, not due either to formation of new protoplasm or to oxidation of the food products, although the latter process may of course play some réle. A similar conclusion has been reached inregard to mammals, as will be considered below. All three methods, susceptibility, carbon-dioxide production and oxygen consumption, demonstrate that in Planaria the total metab- olism is markedly increased in long-continued starvation. The relative susceptibilities of fed and starved animals have been tested by Child not only with cyanide, alcohol and other anesthetics, but also recently with lack of oxygen, a method to which none of the objections possible with the toxic solutions can be raised. It may therefore be concluded that starved worms are in a metabolic condi- tion identical with that of young worms, and that starvation is a means of rejuvenescence. This matter has been so fully treated in Child’s book that further discussion of it is superfluous. The oxygen consumption in starvation rises much more rapidly than does the carbon-dioxide production, and runs more in accord with the results obtained by the susceptibility method than does the latter. It may therefore be suggested that the chemistry of the oxidation processes is different during starvation than in a condition of adequate nutrition. The oxygen consumption rises but the car- bon-dioxide production increases less rapidly so that the organism is apparently carrying on oxidations which do not involve evolution of carbon-dioxide. Perhaps this is due to the fact that it is using its own tissues as a source of energy while ordinarily it is using ingested food. It seems reasonable to suppose that the former can be burned more economically than the latter. Experiments on the metabolism of other animals in relation to feeding and starvation are scanty in number, with the exception of mammals. Among the Protozoa, tests have been made on Paramecium only. Barratt (8) first showed that the carbon-dioxide production of Par- - amecium is decreased during the early stages of starvation. Recently Lund (3), (9) has confirmed this observation and has performed more extended experiments on the rate of carbon-dioxide production and oxygen consumption in feeding and early starvation in this organism. 398 L. H. HYMAN The rates of both proeesses were increased by feeding and decreased in early starvation. Susceptibility to cyanide (of the ectoplasm) was not increased by feeding but increased in starvation. The rise in metabolic rate following feeding is therefore as in Planaria due solely to the activity of the entoplasm, and the fall in rate in early starvation is attributable to decreased activity of the entoplasm. The results with Paramecium as far as they go are therefore identical with our results on Planaria. Lund’s experiments were not carried on for a sufficient length of time to determine whether or not there is an in- creased metabolism in prolonged starvation; this is probably impractical as one would have to know the weight of the organisms. Lund states that the increase in metabolic rate after feeding is the result of “‘in- gestion, digestion and assimilation of the food by the cell leading to growth.’’ It is probable that the activity involved in Paramecium in sweeping food into the gullet and in the formation of food vacuoles would account for a small part of this increase. Digestion may be ruled out, as digestion is chemically a process of hydrolytic cleavage involving neither oxygen consumption nor carbon-dioxide production. It is probable that what Lund really means is the secretion of digestive enzymes, an activity undoubtedly involving an increase in respiratory exchange. Whether assimilation is concerned in the result cannot be decided from the data presented, since the animals were supplied with food throughout the experiment and were continually ingesting food throughout the experiment. If assimilation and growth are really involved in the increased metabolism noted, then they must affect the ectoplasm also. However, the susceptibility method showed that the metabolic rate of the ectoplasm was not increased by feeding, but only by starvation. It may further be pointed out that assimilation as commonly understood and certainly that resulting in the formation of new protoplasm is chemically a process of dehy- dration, involving no increase in rate of respiratory exchange. It seems very likely therefore that in Paramecium the factors mentioned by Lund are not adequate to account for the increased metabolism observed in feeding but that as in Planaria and as has been concluded in regard to mammals, a direct stimulation of the digestive apparatus by the food is involved. Oxidation of the products of digestion may be a factor also. The effects of feeding and starvation on Hydra have been tested in this laboratory but by the susceptibility method only. We have found (10) that in this animal the ingestion of food causes a local OXYGEN CONSUMPTION IN FEEDING AND STARVATION 399 increase in susceptibility. This increase is confined solely to the small region of the column which contains the food and the susceptibility of the rest of the animal is unaffected. Soon after ingestion, the susceptibility falls in this local region. The susceptibility of the entire animal is greatly increased by starvation (one or two weeks), and such starved animals resemble in susceptibility and behavior newly released buds. Conditions in Hydra are therefore like those in Planaria. Some data on other coelenterates are available also through the work of Vernon (11). In some of these forms the rate of respiratory exchange was tested on successive days without food but the experi- ments were unfortunately carried on for a few days only. In two species of ctenophores and two species of Salpa (a pelagic tunicate), the rate of respiratory exchange was found to increase daily when the organisms were kept without food. Such an immediate increase in the absence of food has not been noted in other organisms but may be accounted for in these forms by their extreme delicacy and lack of solid structures which do not permit the storage of excess food; they are hence probably in a state of starvation very soon after cessation of feeding. In other similar coelenterates, two kinds of medusae, the rate of respiratory exchange remained about the same during the period tested, three to four days without food. In these watery coelenterates, then, the metabolic rate ceases to fall or may even rise in very short periods of starvation. In other marine organisms, nudibranchs, octopus, Amphioxus and teleosts, Vernon noted a fall in metabolic rate in the early days of starvation. These forms, whose anatomy permits of food storage, are therefore similar to Planaria, as far as the data permit a comparison. For some time I have been studying the effect of starvation on the metabolic rate of the smaller aquatic oligochaetes, chiefly Tubifex. In this worm, the susceptibility to cyanide increases continuously throughout a period of starvation extending over two months. The carbon-dioxide production, however, falls in the early days of starvation, and increases later. This increase occurs much earlier than in the ease of Planaria, a fact which we attribute to the simpler structure of the digestive tract in: Tubifex as compared with Planaria. In general, however, except for this detail, the metabolic conditions in these worms, in relation to starvation, are like those found in Planaria. In fish, Wells (12) has tested the susceptibility to cyanide during starvation. The susceptibility was found to decrease during the early 400 L. H. HYMAN part of the starvation period and to increase subsequently. Here, contrary to the findings on the lower organisms, the decrease in metabolism in early starvation shows up with the susceptibility method. In the lower forms, it is the susceptibility of the intestine alone which exhibits such a decrease. In these lower forms, susceptibility is measured by the time of death and disintegration of the body surface; in fish by the time of death of the organism as a whole. In this latter case, as Child has suggested, the time of death is probably a more definite measure of the total metabolic rate, since in vertebrates, the cyanide circulating in the blood causes death chiefly by its effect upon internal parts. In fish, then, as in lower invertebrates, the metabolic rate is increased in prolonged starvation. The data upon mammals are so extensive that it would be out of place to attempt to review them in this brief paper. They are ade- quately presented in Lusk’s The Science of Nutrition, in his various papers on animal calorimetry published in the Journal of Biological Chemistry, and in the publications of the nutrition laboratories at Mid- dletown and Boston. This work on mammals agrees with the work on the lower forms. In mammals, the metabolic rate is increased after the ingestion of food. This increase is greatest in the case of ingestion of protein, less in the case of carbohydrates or fats. The cause of the increased metabolism after protein ingestion has been carefully in- vestigated by Lusk and his associates (13) who came to the conclusion that a direct stimulation of the cells by the metabolic products of amino- acids was responsible for the results. Only certain of the amino-acids have this ‘‘specific dynamic action.”” Neither processes of deami- nation nor direct oxidation of ingested protein by the cells could be regarded as responsible since the increase was greatest shortly after ingestion of the protein or amino-acids before a sufficient time had elapsed, as shown by urinea nalysis, for the metabolizing of the in- gested materials to have occurred. Some carbohydrates, such as glucose, also increased the metabolic rate, and the same was true of fat. In both of these cases, the increase was probably due to an actual oxidation of the foods after they had reached the cells (14). In mammals, then, ingestion of food almost invariably increases the metabolic rate, either through a direct stimulating effect of the con- stituents of the food upon the cells, or through the oxidation of the newly available nutritive molecules. The activity of the digestive glands and digestive apparatus apparently plays a negligible réle in the observed metabolic increase. OXYGEN CONSUMPTION IN FEEDING AND STARVATION 401 In mammals as in other forms the metabolic rate soon begins to fall after ingestion. In the experiments quoted above the maximum effect in the case of protein food was observable two to three hours after ingestion, remained high up to about fourteen hours after in- gestion, and then gradually fell. The carbon-dioxide production and oxygen consumption began to fall within eight to ten hours after in- gestion. In the case of carbohydrate food, the increase is at the maximum during the second to fifth hours after ingestion, and in the case of fat attains a maximum by the sixth hour. Studies on prolonged fasts in mammals have shown that the metab- bolism continues to fall during the early days of the fast. Soon how- ever the metabolism attains a nearly constant level and after that begins to rise. The carbon-dioxide production, the oxygen consump- tion and the total heat production, as calculated per kilogram of body weight, rise in the later periods of prolonged fasts. These data are given in Benedict’s report on a fast of thirty-one days by the subject L (15) and in this publication similar results are reported from pro- longed fasts in dogs. In JL, it is also important to note that the rate of the heart beat was distinctly accelerated toward the end of the fast. In mammals, therefore, including man himself, the effect of star- vation is the same as in Planaria and other lower organisms. As a result of starvation, all organisms are restored to a metabolic con- dition resembling that of younger animals. It has been the general impression of men who have undergone long fasts, and observations on dogs confirm this, that they are in a better physiological state after than before fasting. One point still remains to be discussed. It might be maintained that the increased metabolism per unit of weight observed in fasting is only apparent, since it might be supposed that the decrease in weight was due solely to a loss of non-respiring materials. If, however, this were the case, the metabolism as calculated per unit body weight ought to increase in the early days of the fast when this non-respiring material is disappearing most rapidly. This, however, is not the case. Further, the heart loses less material than almost any other part of the body, and hence the increase in the rate of the heart beat in star- vation cannot be attributed to loss of non-respiring materials but must represent a real increase in the basic metabolism of the heart protoplasm. That the intensity of cellular activity is really increased in fasting is the conclusion reached by Benedict frem his study of the metabolism of L in fasting. 402 L. H. HYMAN The increased cellular metabolism in fasting is probably, as Child has long maintained, due to the removal from the cells of reserves, structures and deposits of one kind or another which interfere with metabolic processes. The removal of these hindrances to metabolism restores the cell to an undifferentiated condition like that of young cells and permits a metabolic activity like that of such cells. SUMMARY 1. The oxygen consumption of Planaria is increased markedly after the ingestion of food. 2. This increase is maintained only for several hours after ingestion of food, and the oxygen consumption then begins to fall. By the following day the metabolism has decreased again to a marked degree. 3. The oxygen consumption continues to fall in the early days of starvation, reaching a minimum value within the first two weeks. 4, The oxygen consumption then begins to rise and at the end of a period of prolonged starvation it is much higher than in animals starved only a few days. 5. Data quoted from the work of other investigators show that in other organisms the effects of feeding and starvation on metabolic rate are essentially the same as in Planaria. 6. It may therefore be concluded that starvation increases the metabolic rate of organisms, and that starved organisms are meta- bolically in a condition similar ‘to that of young organisms. BIBLIOGRAPHY (i) Hyman: This Journal, 1919, xlviii, 340. (2) Cuitp: This Journal, 1919, xlviii, 372. (3) Lunp: This Journal, 1918, xlvii, 167. (4) Cuitp: This Journal, 1919, xlviii, 231. (5) Curtp: Biol. Bull., 1913, xxv, 181. (6) Curup: Arch. f. Entw.-Mech., 1911, xxi, 537. (7) Curup: Arch. f. Entw.-Mech., 1914, xxxviii, 418. (8) Barratt: Zeitschr. f. allg. Physiol., 1905, v, 66. (9) Lunp: This Journal, 1918, xlvii, 318. (10) Cut~p anp Hyman: Biol. Bull., 1919, xxxvi, 183. (11) Vernon: Journ. Physiol., 1895, xix, 18. (12) Wetts: Biol. Bull., 1916, xxxi, 441. (13) Wiiirams, Ricoe anp Lusk: Journ. Biol. Chem., 1912, xii, 349; Lusk: Ibid., 1912, xiii, 155. (14) Lusx: Journ. Biol. Chem. 1912, xiii, 27; Muriin anp Lusk: Ibid., 1915, 0-015 i (15) Benepict: Carnegie Inst. of Washington Publ., 1915, no. 203. SUSCEPTIBILITY TO LACK OF OXYGEN DURING STARVATION IN PLANARIA C. M. CHILD From the Hull Zoélogical Laboratory, the University of Chicago Received for publication June 3, 1919 In the course of investigation of the physiological condition of Pla- naria dorotocephala during starvation, the following facts have already been ascertained and recorded in earlier papers: first, that the suscep- tibility of ectoderm and body wall to concentrations of cyanide and vari- ous other agents which are lethal within a few hours increases during starvation (1), (3); second, that susceptibility of the alimentary tract to the same agents decreases rapidly in relation to that of the body wall during the earlier stages of starvation, but later shows some increase (5) ; third, that CO. production also decreases rapidly at first, but later shows some increase (5); fourth, that starved animals appear to be ex- tremely sensitive and show distinctly less capacity for acclimation to certain low concentrations of cyanides and other agents than fed ani- mals, this capacity decreasing during the course of starvation (1), (3). Numerous facts indicate that susceptibility to cyanides and many other toxic agents in sufficient concentration to kill without permitting any marked degree of acclimation or development of tolerance is in a general way and under at least a wide range of conditions, a rough criterion of metabolic condition, the susceptibility varying directly with, though not necessarily proportionally to the rate of metabolism or probably oxida- tion (2), (3), (4). Consequently the increase in susceptibility of ecto- derm and body wall during starvation suggests that the rate of oxidation in these organs increases as starvation progresses, while the decrease in susceptibility of the alimentary tract during the early stages of starva- tion suggests a decrease in rate in this organ in the absence of food. It has been pointed out in another paper (5) that the data on susceptibil- ity and those on CO, production during starvation are not in conflict when the alimentary tract is taken into account. It has been shown that the marked decrease in CO: production during the first few days of starvation is evidently due, at least in large part, to decrease in the 403 404 Cc. M. CHILD metabolic activity of the alimentary tract in the absence of food, and that in advanced stages of starvation, when the alimentary tract, as well as other organs, is undergoing reduction, there is.a distinct increase in total CO. production. The conclusion suggested by the experi- mental data on susceptibility and CO: production is that ectoderm and body wall, which maintain or even increase their functional activity during starvation, show an increase in oxidation rate, while the ali- mentary tract at first undergoes a marked decrease in rate in conse- quence of decreased function, but later, when undergoing reduction, may also show some increase in rate. According to this interpretation, the increase in susceptibility of ectoderm and body wali during starva- tion and the decrease in COs production during earlier stages, followed by increase in later stages, are not in any way contradictory. Suscep- tibility of ectoderm and body wall is a criterion of conditions in these parts only, while CO, production is a measure of conditions in the body as a whole. Since the COz production of the alimentary tract is evi- dently a large part of the total, the changes in the alimentary tract are the chief factor in determining the changes in total COs, and only in later stages of starvation, when the alimentary tract is undergoing reduction, is the increase in CO: production sufficient to balance the earlier decrease, resulting from decrease in functional activity in the alimentary tract. At present this seems to be the only logical and satisfactory interpretation of the facts. Whatever the course of the changes in physiological condition during starvation in Planaria, it is certain that animals which are again fed after a period of starvation are, as regards susceptibility, capacity for acclimation, CO. production, rate of growth and all other distinguish- able characteristics, physiologically younger than at the beginning of the starvation period (1), (3) (4, chap. VII), (5), being in approxi- mately the same physiological condition as well-fed growing animals of their own size or somewhat smaller. In other words, the decrease in size during starvation serves roughly as a measure of the degree of re- gression or rejuvenescence which the animals have undergone. The present paper is concerned with another-aspect of the problem of starvation and its effects in Planaria, viz., the changes in suscepti- bility to lack of oxygen. Since oxygen is essential to the life of Planaria, susceptibility to lack of oxygen may be expected to show some relation to the fundamental metabolic condition. Moreover, various authors have observed that the action of cyanides seems in certaif respects to be similar to that of lack of oxygen and I have found that cyanide in- LACK OF OXYGEN DURING STARVATION IN PLANARTA 405 creases susceptibility to lack of oxygen, i.e., cyanide and lack of oxygen are additive in their action (7). And finally, susceptibility to lack of oxygen is the reaction of the animal to the absence of a factor essential for its fundamental metabolism, rather than to the presence of a toxic agent, and the possible complicating conditions involved in the use of toxic agents for determination of susceptibility are absent. METHOD Since the chlorination of the Chicago city water supply renders this water injurious to Planaria, water pumped from a well is used for all stocks and all experiments with the animals. This water, which be- fore exposure to the air has a very low oxygen content, usually 75 ce. per liter or less, has served as the basis for the experiments on suscepti- bility to lack of oxygen, but the procedure has been modified in various cases by introducing more or less oxygen into the water and thus pro- longing the survival time. The usual method of procedure is as follows: the animals to be com- pared, e.g., well-fed animals and animals starved a certain length of time, or starved animals and animals fed after starvation, etc., are placed together in a pyrex tube about 10 mm. in diameter, closed by fusion at one end, holding 5 to 6 ec. of water and calibrated in cubic centimeters, and this tube is sealed without air bubbles at any desired level, so that the animals are confined in 1, 2 or more cubic centimeters of water. Since the data are purely comparative, the placing of the two or more lots to be compared in the same tube provides identical condi- tions as regards oxygen for all the animals and avoids many complica- tions. Since the animals to be compared in each case are in the same water it maks no essential difference whether the different lots are of equal weight, and in consequence of the oxygen consumption of all the animals in the tube the oxygen concentration is undergoing continuous decrease and the most susceptible animals must die first. Of course the actual survival time of the lots and the amount of difference be- tween them will vary with different conditions in the tubes but the es- sential point, i.e., whether one lot is more or less susceptible than an- other, is readily determined by this method. It is not even necessary to know the oxygen content of the water in a particular experiment, if the precautions mentioned below concerning CO, are observed. Several methods of sealing the tubes have been used. One of these which avoids exposure of the water to air, consists in the insertion of 406 Cc. M. CHILD a small tight plug of absorbent cotton to any desired level in the tube while both tube and cotton are held well below the surface of a large volume of the water coming directly from the pump and then sealing above the cotton with melted paraffine. Since leakage occasionally occurs around the paraffine, particularly if changes in temperature oc- cur, the entrance of air is prevented by placing a tightly fitting soft rub- ber tube 2 to 3 em. long over the open end of the glass tube, filling both glass and rubber tube with the water used and closing with a screw clamp. Air may of course be excluded by the rubber tube and clamp alone, but the animals are likely to creep into the rubber tube out of the light and die there, and since they tend to stick to surfaces when they begin to die they cannot readily be removed to the glass tube, where they can be seen. The cotton plug serves merely to avoid ex- posure of the water in the tube to the air and to remove the possibility of injuring the animals by temperature changes when the melted par- affine is run in. If care is taken to keep the animals at the bottom of the tube the paraffine may be run in directly on the surface of the water, though this necessitates exposure of this small surface to the air for a short time. In most cases lots of 3 to 5 worms each are used, and when starved and well-fed animals are compared there is no difficulty in distinguish- ing the animals of the two lots, even when they are of the same size. In cases where it may be difficult to distinguish animals of different lots, the tips of the posterior ends of one lot may be cut off. This or some other slight injury does not alter the susceptibility to any appreciable degree, except in the immediate region of the injury. Since the animals not only consume oxygen, but produce COk, it is necessary to make certain that death results from lack of oxygen and not from accumulation of COs. The well water when first pumped con- tains a slight excess of COo., and pH = 7.4 +. It was determined ex- perimentally by running washed CO, into flasks of well water containing a little of the proper indicator and some planarians and sealing at different values of pH, that death of the animals from CO: does not be- gin to occur until pH = 5.5 to 5.0 approximately. Susceptibility to COs, as to other agents, decreases with advancing age and differs with nutritive and other conditions, so that the minimum lethal concentra- tion of CO, differs somewhat for different animals. By adding to the water a little of the proper indicator it is possible to determine the pH at which the animals die in water containing various amounts of oxygen. In this way it has been found that in the low oxygen water LACK OF OXYGEN DURING STARVATION IN PLANARIA 407 directly from the well they usually die while pH > 7.0, while with the various degrees of aeration used, death almost always occurs before the pH has decreased below 6.0. In other words, even in the aerated water the animals die before they have produced enough CO, to kill any of them and in the low oxygen water they die when or before the accumula- tion of CO, has decreased the pH to neutrality. As regards the low oxygen water then there can be no doubt that it is lack of oxygen, not COs, that kills, and even in the aerated water lack of oxygen is at least the chief if not the only factor in producing death, although the increas- ing H ion concentration may alter the amount of difference in suscepti- bility of the different lots. In many series, however, a little NaOH has been added to the water in order to avoid all possibility of injurious H ion concentration berore the animals are killed by lack of oxygen. With the low oxygen water NaOH is unnecessary but, as noted above, in aerated water, the H ion concentration sometimes approaches the danger point before the ani- mals die from lack of oxygen. The lower limit of lethal concentration of NaOH for the animals is between m/450 and m/500 so that the well water may be made up to any concentration below m/500 with the cer- tainty that the NaOH is not itself lethal. The well water made up to NaOH m/500 has a pH = 9 to 9.5 according to the amount of CO: in the water and with lower concentrations of NaOH the pH of course lies between 9.5 and 7.4. The addition of NaOH to the water increases the susceptibility to lack of oxygen even when the concentration is far below the lethal limit, e.g., m/1000 or m/2000, and in general the sur- vival times in water with a given oxygen content decrease as the NaOH ‘concentration increases. In the higher concentrations of NaOH, e.g., m/750 made up in low oxygen water the animals may die from lack of oxygen at pH 8.6 or above and in aerated water at pH 7.0 or above. The use of NaOH in this way makes it possible to bring about death from lack of oxygen at any point within a considerable range of pH on the alkaline side of neutrality. As might be expected, it is found that the amount of difference in susceptibility of two lots of animals differs with the volume of water used, the oxygen content, the number and size of the animals in the water, the pH at the beginning and the amount of change in pH before death occurs, and some of these factors are mutually related. In no case, however, within the limits indicated, do these factors alter the gen- eral susceptibility relations of the lots compared, i.e., the susceptibility of a lot in a particular physiological condition is always greater than 408 Cc. M. CHILD that of another lot in a different condition, in all the modifications of the experimental method described, though the amount of difference may vary to a considerable degree with the different conditions of experiment. Some of these differences will appear in the data presented below, but since the paper is primarily concerned with the effect of starvation on susceptibility to lack of oxygen, the point of chief importance is the increase or decrease in susceptibility with change in nutritive condition, and the degrees of difference with different ranges of H ion concentration and other experimental conditions have to do with other problems. In all cases recorded below where susceptibilities are directly compared, the experimental conditions, except as regards nutrition or physiologi- cal age, are either identical or the differences are noted. With very few exceptions only lots in the same tube are directly compared. Two criteria may be used in determining susceptibility to lack of oxygen; first, the loss of muscular coérdination with consequent loss of ability to attach the body to the glass, and the cessation of motor ac- tivity which soon follows; second, by the disintegration of the body, both methods giving similar comparative results. As regards both these changes, the body of each individual, except in the more advanced stages of starvation, shows a gradient in susceptibility similar to the gradient in susceptibility to cyanides and other agents, the head region being most susceptible (6). In the later stages of starvation the body is usually almost as susceptible as the head, sometimes more so. The data on susceptibility are most simply presented in graphic form, and the method adopted for graphing is briefly as follows: since the ef- fects of lack of oxygen, both as regards cessation of movement and dis- integration usually begin at the head and progress in an orderly manner along the body, it is possible to distinguish more or less arbitrarily three or four stages in the course of each of these processes. Assigning to each of these stages a numerical value, e.g., stage I, 10; stage II, 20, etc., it is then possible to obtain a numerical value for the average con- dition of each lot of worms at any given time during the experiment by multiplying the number of worms in each stage by the numerical value for that stage, adding the products and dividing their sum by the number of worms in the lot. These values may then be plotted as or- dinates against times as abscissas. By measuring the ordinates down- ward from a distance above the axis of abscissas equal to the longest possible ordinate, the curves of susceptibility appear as descending curves which reach the axis of abscissas when all worms of the lot have at- tained the final stage, or by reversing the order of the numerical values LACK OF OXYGEN DURING STARVATION IN PLANARIA 409 of the stages and measuring upward from the axis of abscissas the same result is obtained. In the following figures the curves are all drawn as descending curves. This method of graphing susceptibility data is de- scribed in detail elsewhere (4, p. 81, footnote). With this method the difference in time measured on the axis of abscissas between the upper end and the base of the curve represents the entire time from the begin- ning to the end of the process of change concerned, either loss of motility or disintegration, and the course of the curve represents in a general way the progress of the change from the head along the body. The less the distance of the curve from the axis of ordinates, the greater the sus- ceptibility, and vice versa. The following graphs are plotted in this way, the time intervals indicated on the axis of abscissas being two hours each and the divisions on the axis of ordinates representing the stages. It should be noted that these data on susceptibility to lack of oxygen concern ectoderm and body wall and probably the nervous system, but not the alimentary tract. For the loss of motility, changes in cilia, muscles or the nervous system or all three are responsible, but as re- gards disintegration, oxygen must pass through the body wall to reach the alimentary tract, and when the oxygen content of the water be- comes so low that it is not sufficient to maintain the life of ectoderm and body wall, it is probable that very little oxygen is reaching the alimen- tary tract. Asa matter of fact the alimentary tract appears to disinte- grate at about the same time as the body wall, but under the conditions of the experiment this fact can have little or no significance. The standardization of starvation stocks has been discussed in an earlier paper (5), and it need only be said here that the methods of stand- ardization described have been followed with all material used in these experiments, in order that all animals of a given lot should be as nearly as possible alike, not only as regards size and nutritive condition, but as regards the occurrence of fission and regulation. THE INCREASE’ IN SUSCEPTIBILITY DURING STARVATION It may be stated at once that all experiments performed, twenty-two _in number, each consisting of two or three lots of from three to five worms each in the same tube or small flask, show that susceptibility of ectoderm and body wall to lack of oxygen increases during starvation, at least up to four months, longer periods not having been used. Since the results are essentially the same in all cases, the differences being THE AMERICAN JOURNAL OF PHYSIOLOGY, VOL. 49, NO. 3. 410 Cc. M. CHILD merely differences in the degree of susceptibility, dependent on the conditions of different experiments, it is quite unnecessary to give data or graphs for all series. The following series show the character of the results and some of the differences under different experimental conditions. Series 708. Figure 1. Lot I. 3 animals 15 mm. Well fed. Lot II. 3 animals, originally 15 mm., starved 37 days. At time of experiment 12 to 13 mm. Lot III. 3 animals, originally 15 mm., starved 99 days, now 7 mm. These three lots were sealed in a tube in 8 cc. of m/1000 NaOH in well water of low oxygen content. The curves ab, cd, ef (fig. 1) show the susceptibility to lack of oxygen of lots I, II and III respectively in terms of loss of motor activity and the curves a’b’, c’d’ and e’f’ show the susceptibility in terms of disintegration. The broken line in the lower part of ab indicates that observations’ were concluded before all animals of this lot were entirely disintegrated. The fed animals of lot I are least susceptible, those of lot II, starved 37 days, much more susceptible and those of lot III, starved 99 days, most susceptible to lack of oxygen, both as regards loss of motor activity and disintegration. More- over, the relative susceptibilities of the different lots are very nearly the same in terms of loss of motor activity as in terms of disintegration. This is a perfectly characteristic series. With higher oxygen content, greater volume of water or lower alkalinity the susceptibility curves lie farther to the right and farther apart than in figure 1 but their relative positions are not greatly changed. -_ LACK OF OXYGEN DURING STARVATION IN PLANARIA 411 Series 614. Figure 2. Lots Ia, IIa. Each 3 animals, 25 mm., well fed. Lots Ib, Il b. Each 3 animals originally 25 mm.; starved 39 days and under- went fission once during starvation; length at time of experiment 12 to 14 mm. Lots I a and I b were sealed in one tube in 5 cc. NaOH m/3000 and lots II a and II b in another tube in 5 ec. NaOH m/2000, both slightly aerated. The curves in figure 2 show the susceptibilities in terms of disintegration as follows: ab lot I a; cd lot I b; ef lot Il a; gh lot II b. In both pairs of lots the animals starved 39 days are far more susceptible than the well-fed animals. Since the two pairs of lots were in two different tubes, they are perhaps not strictly comparable, although, except as regards concentration of NaOH, condi- tions in the two tubes must have been very nearly identical, both containing the hi oe WA Fig. 2 same number of worms of the same two sizes and the same nutritive conditions in the same volume of water. Figure 2 shows that the susceptibility in NaOH m/2000 (curves ef, gh) is somewhat greater than in NaOH m/3000. While slight differences in weight, physiological condition, oxygen consumption or oxygen content may exist in the two tubes, the differences in susceptibility indicated by the differences in position of the two pairs of curves, is too great to be the result of such incidental differences and is undoubtedly due, at least in large part, to the difference in concentration of NaOH in the two tubes, the susceptibility being greater in the higher concentration. Other series have given similar results. Series 715. Figure 3. Lot I. Posterior halves of animals originally 25mm. Starved 59 days; under- went regulation to whole animals during early stages of starvation; at time of ex- periments 8 to 9 mm. 412 Cc. M. CHILD Lot II. Posterior halves of animals originally 25 mm. Starved 121 days; un- derwent regulation to whole animals during early stages of starvation; at time of experiment 4 to 5 mm. The two lots of three animals each were placed together in a tube in 2 ce. of low oxygen water made up approximately to NaOH m/500 withas little exposure to air as possible and containing 1/150,000 phenolsulphonephthalein. Curve ab of figure 3 shows the disintegration of lot I, curve cd that of lot II, the more advanced stage of starvation being the more susceptible. The high susceptibility of both lots is due to the high concentration of NaOH. This con- centration, m/500, was not lethal for animals from the same stocks as the experi- mental animals in a tube open toair. In this experiment the animals died from lack of oxygen before the pH had fallen below 8.6. ca ae a Fig. 3 Fig. 4 Series 737. Figure 4. Lot I. Four animals 16 mm., well fed. Lot II. Four animals originally 16 mm., starved 18 days;‘not appreciably reduced in length. Both lots together in a tube in 7 ec. water containing 1/150,000 phenolsulphone- phthalein, but no alkali; water aerated; pH at beginning 7.9. The curve ab in figure 4 shows the disintegratign of lot I, the fed animals, curve cd that of lot II, the animals starved 18 days. As in other experiments the susceptibility of the starved is greater than that of the fed animals. Since no alkali was added in this series and the water contained considerable oxygen, it became distinctly acid, pH 6.0, before all the animals died. Under these condi- tions the susceptibility of both lots is less and the difference between the two lots greater than in water with very low oxygen content or with higher alkalinity. LACK OF OXYGEN DURING STARVATION IN PLANARIA 413 The point of chief interest, however, is that, even with the short starvation period of eighteen days and with no appreciable decrease in size, the susceptibility of the starved animals is distinctly higher than that of the fed animals which represent as nearly as possible the condition at the beginning of starvation. DIFFERENCES IN SUSCEPTIBILITY TO LACK OF OXYGEN BETWEEN YOUNG AND OLD ANIMALS It has been shown elsewhere that susceptibility to KNC and rate of CO, production decrease in Planaria with advancing physiological age and that starving animals show changes in the opposite direction (3), (4), (5), i.e., according to these criteria of physiological age the starving animals become younger. The data of the preceding section show that susceptibility to lack of oxygen increases during starvation and in order to determine whether in this respect also the starving animals undergo changes in the opposite direction from those of progressive develop- ment and advancing age, it is necessary to determine what changes in susceptibility to lack of oxygen occur in relation to age in well-fed growing animals. Comparative determinations of susceptibility to lack of oxygen in animals of different age have been made many times and by different persons in this laboratory, the experiment having been used in labora- tory classwork. In these experiments where all animals are well fed, size of animals is used as the most satisfactory criterion of physiological age, for the larger animal has undergone more growth and if a progres- sive senescence occurs in the species, the larger animal must be physi- ologically older than the smaller. In all experiments with well-fed ani- mals, the smaller younger individuals are more susceptible to lack of oxygen than the larger and older. Graphs of a few characteristic experiments are given in figure 5. Series 665. Lot I. 5animals,25mm. Lot II. 5 animals, 6 to7 mm. Both lots from well-fed laboratory stock together in 125 ce. of slightly aerated water. Curve ab shows susceptibility of lot I, the old animals, curve cd that of lot II, the young animals. The long survival times, 65 hours for lot I and 31 hours for lot II, are due to the large volume of water. Series 664. Lot I. 5 animals, 20 to25mm. Lot II. 5 animals, 7 mm. Both lots from well-fed laboratory stock, together in 125 cc. of low oxygen water made up to NaOH m/2000 with as little exposure to air as possible. Curve ef shows susceptibility of lot I, curve gh that of lot IT. Series 751. 414 C. M. CHILD Lot I. 5animals, 18mm. Lot II. 5 animals, 7 mm. Both lots from a stock freshly collected in midwinter and fed only three times in the laboratory. Such worms contain less nutritive reserves than animals which have been a long time in the laboratory. Both lots together in 5 ce. of water made up to NaOH m/750 and slightly aerated. Curve 77 shows suscepti- bility of lot I, curve kl that of lot II. Series 754. : Lot I. 5animals,20mm. LotII. 5 animals, 5mm. From same stock as preceding series. Both together in 3 cc. of low oxygen water. Curve mn shows susceptibility of lot I, curve op that cf lot I] OWE os Baw an a ( Fig. 5 In these four series the ages compared, the volume, oxygen content and alkalinity of the water differ, consequently only the two curves of each pair are comparable, but in all series the younger animals are dis- tinctly more susceptible to lack of oxygen than the older, though the ~ actual susceptibility and the degree of difference differ with the condi- tions. There can be no doubt that this difference in susceptibility to lack of oxygen between animals of different size and therefore of dif- ferent physiological age, indicates a real difference in physiological con- dition. Moreover, since these data make it clear that susceptibility to lack of oxygen decreases with advancing age and since it was shown in the preceding section that susceptibility to lack of oxygen increases during starvation, it is evident that the changes during starvation are LACK OF OXYGEN DURING STARVATION IN PLANARIA 415 opposite in direction to those during growth and progressive develop- ment, i.e., as regards susceptibility to lack of oxygen, the starving ani- mals become progressively younger. - ~ COMPARISON OF STARVED AND FED ANIMALS OF THE SAME SIZE The starving animals decrease in size and it is of interest to deter- mine how the rate of increase in susceptibility to lack of oxygen com- pares with the rate of decrease in size. To obtain evidence on this point the starved, reduced animals are compared with well-fed, growing ani- a (G ac | 6 dad 6 qd Fig. 6 Fig. 7 mals of approximately the same size. Only five experiments of this sort have been performed, but the results are the same in all cases, the starved animals being somewhat more susceptible than the young fed animals. The data of three series are given. Series 755. Figure 6. Lot I. 3 animals, starved 42 days. Reduced from 8 mm. to 5 mm. Lot II. 3 animals from well-fed laboratory stock; 6mm. (smallest of stock). Both lots together in 4 cc. of low oxygen water. Curve ab, figure 6, shows sus- ceptibility of lot I, curve cd that of lot IJ. Here the fed worms of lot II were slightly larger than the starved animals of lot I. Series 757. Figure 7. 416 . Cc. M. CHILD Lot I. 3 animals, starved 42 days. Reduced from 8 mm. to 5 mm. Lot II. 3 animals from well-fed laboratory stock; 5 mm. Both together in 3 ce. low oxygen water. Curve ab, lot I; curve cd, lot II. Series 761. Figure 8. C Lot I. 3 animals, starved 79 days. Reduced from 10 to 12 mm. to 4mm. Lot II. 3 animals from freshly collected stock fed three times in the labora- tory; 4 mm. Together in 3 cc. low oxygen water; Curve ab, lot I; curve cd, lot II. In all three series the higher susceptibility of the starved worms is evident: the differences in the three are dependent upon the differences in size and nutritive condition of the fed, as compared with the starved AE ac 6d od Fig. 8 Fig. 9 animals and upon differences in volume and oxygen content of the water, possibly also to some extent upon the stage of starvation (see p. 403). Although in the earlier work on susceptibility to KNC attention was not particularly directed to this point, it was, noted that the suscepti- bility of starved animals was frequently somewhat higher than that of fed animals of the same size (3, p. 483), and one series is given here. Series 557 ITI. Figure 9. Lot I. 10 worms, starved 81 days. Reduced from 10-12 mm. to 5-6 mm. Lot II. 10 worms, well-fed;5 to6mm. From freshly collected stock. Curve ab, figure 9, shows the susceptibility of lot I, curve cd that of lot II to KNC m/1000. LACK OF OXYGEN DURING STARVATION IN PLANARIA 417 With the method and scale of graphing, which is the same as that of the preceding figures, the differences in susceptibility appear to be slight, but actually the susceptibility of the starved worms is only about 75 per cent that of the fed animals of the same size. Similar differences have been observed in many other KNC series, but they seem to occur more frequently when the animals were of medium size at the begin- ning of starvation than when they were very large. It is possible that in the extreme stages of starvation which occur when very large animals are reduced by starvation to small size, the increase in susceptibility does not keep pace with the decrease in size, but further work is neces- sary to settle this point. It is certainly true that animals after one to three months of starvation are very commonly more susceptible to KNC and in all cases thus far observed are more susceptible to lack of oxygen than fed, growing animals of the same size. CONCLUSION The experimental data demonstrate that during starvation suscepti- bility to lack of oxygen increases, at least in ectoderm and body wall, the method not being suitable for determining conditions in the ali- mentary tract. This increase in susceptibility parallels very closely the increase in susceptibility to KNC which occurs during starvation. In both KNC and lack of oxygen it is primarily susceptibility of ectoderm and body wall that is determined, though in KNC the susceptibility of the alimentary tract may be roughly determined as differing either more or less from that of ectoderm and body wall (5, p. 253). The data on CO, production, however, represent COs production of the alimen- tary tract as well as that of ectoderm and body wall, and it has been pointed out (5) that the decrease in CO: production during the earlier stages of starvation is very largely, if not wholly due to the decrease in metabolic activity of the alimentary tract in the absence of food. In the later stages of starvation even the total CO, production increases. The data on susceptibility to lack of oxygen constitute a further con- tribution to the problem of starvation. The experiments with animals of different age show that susceptibility to KNC (8), (4) and lack of oxygen and rate of CO» production (5) decrease with advancing age, and Doctor Hyman has found that oxygen consumption also decreases dur- ing senescence. In short, all the evidence indicates that susceptibility to lack of oxygen in fed, growing animals varies directly with rate of oxidation. In starving animals susceptibility to KNC and to lack of 418 Cc. M. CHILD oxygen increases, CO. production also increases, except for the initial decrease noted above, and Doctor Hyman’s work shows that oxygen consumption also increases after an initial decrease due to the same factor as the decrease in CO» production. The only logical conclusion on the basis of all the evidence is that the rate of oxidation increases during starvation, in ectoderm and body wall from the beginning and in the alimentary tract in later stages after the initial decrease due to decreased functional activity. If this conclu- sion is correct, susceptibility to lack of oxygen is, as might be expected, in some degree a measure of rate of oxidation in ectoderm and body wall. The only other possibility as regards the starving animals is that cer- tain oxidative reactions which require a higher oxygen concentration than those characteristic of fed,. growing animals, occur in increasing proportion as starvation advances, but there is at present no evidence in favor of this hypothesis. Apparently the starving planarian oxidizes its own substance with increasing rapidity as starvation advances and the products of metabolism accumulated during growth and progres- sive development are broken down and removed. The inactive ali- mentary tract undergoes atrophy and resorption more rapidly than ec- toderm, body wall and nervous system and undoubtedly constitutes the chief source of nutrition for the other functionally active organs after the reserves are exhausted. As regards the rate of its fundamental metabolic reactions, the starving animal unquestionably becomes pro- gressively younger, and when it is again fed after a period of starvation, it is in essentially the same physiological condition, as regards suscepti- bility to KNC (3), (4) and lack of oxygen, rate of CO: production (5) and oxygen consumption (Hyman), as well as rate of growth, as a fed, growing animal of the same size. If feeding is continued, such an ani- mal passes again through the progressive stages of the life history of the species from the point at which feeding began. The experimental data on the effect of feeding after starvation have not yet been pre- sented in detail and must be reserved for another paper. SUMMARY 1. Susceptibility of ectoderm and body wall of Planaria dorotocephala to lack of oxygen, as measured either by loss of motility or by disinte- gration, increases progressively during starvation, up to at least four months. LACK OF OXYGEN DURING STARVATION IN PLANARIA 419 2. The susceptibility to lack of oxygen of the animal reduced by star- vation is about the same as, or slightly higher than that of a fed, growing animal of the same size. : 3. The change in susceptibility to lack of oxygen during starvation is in the opposite direction from that which occurs during growth and progressive development in fed animals, and in the light of the facts al- ready at hand concerning CO, production, oxygen consumption and sus- ceptibility to KNC, must be considered as evidence of an increase in rate of oxidation during starvation. BIBLIOGRAPHY (1) Cmiup: Arch, f. Entwickelungsmech., 1911, xxxi, 537. (2) Cuitp: Journ. Exper. Zo6l., 1913, xiv, 153. (3) Cuitp: Arch. f. Entwickelungsmech., 1914, xxxviii, 418. (4) Curtp: Senescence and rejuvenescence, Chicago, 1915. (5) Cuitp: This Journal, 1919, xlviii, 231. (6) Curtp: Arch. f. Entwickelungsmech., 1913, xxxvii, 158. (7) Curttp: This Journal, 1919, xlviil, 372. QUANTITATIVE STUDIES ON THE RATE'‘OF RESPIRATORY METABOLISM IN PLANARIA II. Tae Rate oF OxyGEN CONSUMPTION DURING STARVATION, FEED- ING, GROWTH AND REGENERATION IN RELATION TO THE METHOD OF SUSCEPTIBILITY TO PoTASSIUM CYANIDE AS A MEASURE OF RATE oF METABOLISM GEORGE DELWIN ALLEN From the Department of Animal Biology, University of Minnesota Received for publication June 9, 1919 INTRODUCTION A review of the literature concerning the réle of what has been desig- nated ‘‘rate of metabolism” in senescence, rejuvenescence and gradi- ents along the body axes in lower animals ((1) to (9) and other refer- ences there cited), will show that little or nothing is known which is based on direct quantitative measurements of metabolism in the ani- mals concerned. It has been assumed that relative susceptibility of an organism to the toxic action of potassium cyanide and other substances is a measure of rate of metabolism or rate of oxidation. This assump- tion has been used extensively as the basis for inferences regarding the metabolism in Planaria and other animals. The only attempts to measure the metabolism in these forms by methods which do not in- volve assumptions are certain tests reported by Child, (3, pp. 422, 434; 4, pp. 73, 161, 202) of carbon dioxide production by Planaria in Tashiro’s ““biometer.”” These estimations were few in number, comparative not strictly quantitative, and we cannot judge from the account how carefully they were controlled. The purpose of the present paper is to present quantitative information regarding the oxidations in Planaria in relation to starvation and feeding, increase in size of the body, and regeneration; and secondly, to compare these results with the reported differences in the susceptibility of Planaria to potassium cyanide. The term metabolism is commonly used in animal calorimetry to refer to the decomposition of organic compounds (total katabolism) 420 as 2 Aweraod STUDIES ON RESPIRATORY METABOLISM IN PLANARIA 421 yielding energy. It may be considered either from the standpoint of the quantities of the different foodstuffs decomposed and the complete- ness of this decomposition or from the standpoint of the quantities of energy yielded. The latter basis is used for expressing metabolism in a Single quantitative term. Lusk, for example, says with regard to the “exact measurement of the metabolism”’: Thus heat may become a measure of the total activity of the body. It is de- rived from the total metabolism and must be dependent on it and be a measure of it (10, p. 32). From this standpoint the oxidations are considered important as a source of energy and as a measure of the energy production. The term “‘rate of metabolism”’ seems to be used in this sense in some of the ref- erences on senescence and axial gradient, especially where studies of the metabolism of man and mammals are quoted (e.g., (4, pp. 63, 65, 271-273, 297-298) ). The following statements seem to imply this meaning of the term. There can be no doubt that the rate of metabolism or, more specifically, of oxi- dations inthese animals increases during the course of starvation (3, p. 435). It has been shown that a relation exists between susceptibility and metabolic activity, more specifically the oxidations or energy-freeing reactions (6, p. 50). It is not certain, however, that the term is always used in the litera- ture concerning ‘‘rate of metabolism’ as equivalent to the rate of oxidations or of energy production. A distinction seems to be drawn between them in accordance with the following statement: While oxidations are fundamental metabolic reactions, and serve in a general way as a measure of metabolic activity, a considerable range of variation in the - different reactions which go to make up the metabolic complex may undoubtedly exist (4, p. 72). A fact which must be kept in mind in using the term metabolism is that while energy transformation in the cell may be large, the corre- sponding quantity of material transformed may be small. This is true of respiratory metabolism, while on the other hand in a large num- ber of metabolic processes the quantity of material being transformed is relatively very large while.the energy change is hardly measurable. As pointed out by Lund (11, p. 168): 422 GEORGE DELWIN ALLEN It is very doubtful if the rate of oxidations as measured by carbon dioxide pro- duction or oxygen consumption can even approximately’ be used as a measure of the rate of total metabolism (either of matter or energy") in a cell, for it has never been shown that the speed of such processes as hydrolyses and changes in colloidal constitution are correlated to the speed of oxygen consumption or carbon dioxide production. Furthermore, these processes are of a reversible character and mat- ter and energy may pass through them repeatedly before appearing in the external exchanges of the animal. It is evident from these consid- erations that the terms metabolism and rate of metabolism may be and are used in different senses. On the one hand they may refer strictly to the rate of oxidations or more generally to the rate of energy produc- tion as measured by oxygen consumption, carbon dioxide production or heat liberation. On the other hand they may refer in a loose way to the rate of all metabolic processes, involving the complications just mentioned. ‘These two usages are by no means equivalent. It is of vital importance to any profitable discussion of the rate of metabolism in organisms that it shall be clearly understood precisely what is under discussion. This matter cannot be over-emphasized. It is not a ques- tion of quibbling over the propriety of one definition as contrasted with another, which is a very unessential matter. But it is extremely im- portant that there shall not be ambiguity as to meaning at any given point, and that an unconscious and unwarranted translation of fact into inference shall not be made. Statements regarding the rate of metabo- lism,may be true when the term means one thing while the same state- ments may be untrue when the term means something else. If an es- tablished fact regarding the rate of metabolism in one sense is used as the basis for an inference regarding the rate of metabolism in a different sense, then great care must be exercised that the inference does not be- come confused with the fact. The present paper is concerned with the rate of metabolism in the sense of rate of energy production, with the usual qualifications concerning errors in the different methods of direct and indirect calorimetry, and of the possibility of other sources of en- ergy than that represented by the respiratory exchange (see Krogh, (12), chap. i). This statement is made for the purpose of avoiding any ambiguity, and of guarding against the reading into the discus- sions of more than is intended. ! Italics and parenthesis mine. — » ment BPN res il Steed. rie STUDIES ON RESPIRATORY METABOLISM IN PLANARIA 423 METHODS Two species of Planaria, P. maculata and P. agilis,* were used in the experiments reported in this paper. The general method for determin- ing the amount of oxygen consumed was to place worms in a bottle of tap water of known content of dissolved oxygen for a stated period of time, and then to remove the worms and analyze the water by the Winkler method for the amount of oxygen remaining. A large carboy was filled with tap water and stirred to make sure that the amount of dissolved oxygen was uniform throughout. The bottles used in an ex- periment were filled in rapid succession, and the average of the analy- ses of three or four blanks containing no worms during the experi- ment was taken to represent the amount of oxygen in each of the ex- perimental bottles at the beginning of the experiment. All bottles were of the same capacity, 132 ec. During analysis the amount of water displaced by the 2 cc. of reagents added is lost. As explained in a previous paper (13, p. 98) removing worms at the end of a test may remove enough water to make it difficult to close bottles after adding the reagents without leaving air bubbles. This can be prevented by adding more reagents or by inserting a glass rod of known volume. In the experiments summarized in tables 3, 4, 5, 6, 8, 12 and 13 the re- agents were diluted with an equal volume of distilled water and 2 cc. instead of 1 cc. of each were used. In the other experiments, glass rods of 2 cc. volume were used. The latter method appears preferable al- though it is unnecessary, if the worms in a single bottle are not too numerous and do not cling too firmly to the glass. The experimental methods are described in more detail in the previous paper. It was shown in that paper (13, table 1) that when 28 bottles were filled with _ aerated tap water and analyzed at once, the maximum difference be- tween individual analyses did not exceed 0.08 cc. thiosulphate. In the experiments reported previously 15 sets of three or four blanks were analyzed. In no case was the maximum difference between duplicate analyses greater than 0.06 cc. thiosulphate. For the experiments re- ported in the present paper 37 sets of blanks were analyzed. In one case a difference of 0.12 cc. thiosulphate was noted between duplicate analyses, but this was apparently an error in the reading. In only one other instance did the maximum difference amount to so much as 0.09 ec. thiosulphate. For all the experiments of both papers the average 2 IT am indebted to Dr. Ruth Higley for verifying the identification of these species. 424 GEORGE DELWIN ALLEN difference beteen the maximum and the minimum analyses in a series of blanks was 0.046 cc. thiosulphate. One drop of thiosulphate from the burette used averages 0.06 cc. in volume. (Titrations were made in a porcelain dish.) These figures therefore indicate the limits of ex- perimental error in the method used and enable one to form a judgment of the accuracy of the data presented in the tables and curves. The methods of weighing worms have not been described. In the earlier experiments reported in this paper, worms were removed indi- vidually to a glass plate in a drop of water, the excess water was ab- sorbed with filter paper and the worm was transferred by means of a probe to a moistened filter paper in a weighing dish. All of the worms which were together in the same bottle in a respiration test were weighed at once, not individually. The error from evaporation was found to average 0.0005 gram. In later experiments a better method was fol- lowed. All the individuals from one bottle were transferred in a drop of water to a glass cover slip, the excess water was absorbed with filter paper, and the cover slip was dropped quickly into a weighing bottle half filled with water. When a weighing bottle with a well-ground stopper was used, the error from evaporation was only 0.0002 gram and was much less variable than in the earlier method. These average errors were added to the observed weight in each case. In order to test the limits of error in the method just described, a single set of worms was weighed repeatedly, as shown in table 1. The worms were weighed three times in rapid succession, and then were al- lowed to rest undisturbed for a few hours before the next series of weigh- ings. It appeared at once that the first determination in a series was always highest and that the later ones were successively lower. The difference between the first and the third weight was sometimes over 6 per cent. This apparent loss was not permanent, however. After each period of rest the first weight was considerably higher than the last, and almost as high as the first weight of the preceding series. Figure 1 shows these relations graphically. These peculiar results are due, probably, to differences in the amount and character of the mucus. At the moment when excess water is removed from the group of worms on the cover slip, thicker mucus will retain more water; and since care must be exercised not to injure worms by excessive drying, they can- not safely be freed entirely from mucus. Figure 1 shows that the first weights of the different sets make a very regular series decreasing with time and starvation, in which individual variation did not reach 2 per cent. In order to weigh worms under uniform conditions in experi- SR i cn ll a et AE 7 STUDIES ON RESPIRATORY METABOLISM IN PLANARIA 425 ments, all sets were left undisturbed under dark cloth for some time, each set in a separate dish of water, and each set was taken for weighing with as little disturbance to the others as possible. In experiments extending over a considerable period of time, the worms were weighed at intervals and the weights were plotted on a graph as in figure 2. The weight of each lot of worms at the middle of TABLE 1 Showing variation among successive weights of a set of Planaria agilis. Five large worms were weighed three times in rapid succession, then were left undisturbed for several hours under dark cloth and were weighed again as before, etc. DATE TIME WEIGHT 10.50 a.m. 0.0294 JWI? Pcie BOS CORD OC Ce MENS ORE nO RoC ECE RS eee 11.06 a.m. 0.0283 11.24 a.m. 0.0281 1.30 p.m. 0.0292
    < 3 ° Blanks Blanks Blanks eT es cc. thio. average cc. thio. average cc, thio, average ~ 8] 1 4.56 4.42 4.29 a Pe 2 4.53 4.54 4.44 4. dd 4.25 4.26 S| 3 4.54 4.45 4.25 mel 4 4.54 4.44 4.24 (1) (2) (3) (4) (5) (6) (7) (8) (9) (10) 2 AZ ao 12 ag 3 Hy 4% Ag a i st po |Se [fs | #2, /288783 | #2, |888/ 22 [ee OF | bag a Dow | poe a aoe |bO8 a 2og PO | eealer | Fee | 2's | az | eel eS | wz | 8,2 Bol ere ere) Sen | 6a8| So) Sameer duern | o Re aS ze@|egalz a zee |ega|e S| 282) 29 |x x a@ | o8e| ose |oge/8,28|/855|8Se)e.8| S85 | Seu 22) ma | ePa| hee | pee | see | Pee | hee] Bee | eR Z ° 3 ° ° = ° ° 4 ° At end of 7 days star- At end of 9 daysstar- | At end of 11 days star- vation vation vation cc, thio.) grams Legon cc. thio.| grams |cc. thio. Gen grams pean § 1 5 | 1.60 0.0318] 4.3 | 1.53 [0.0304] 4.3 | 1.13 [0.0290 | 3.6 2 5 | 1.68 |0.0332) 4.4.) 1.52 |0.0811} 4.2 | 1.02*10.0244* 3.8 I 3 5 | 1.76 |0.0399} 3.8 | 1.66 |0.0384) 3.7 | 1.41 |0.0369 | 3.5 B Average.. TOS NOLOSb0\) Zo W100 NO. 0838S a ele LOnMOZOS0L | 3.6 At end of 63 daysstar- | At erid of 65 days star- | At end of 67 days star- vation vation vation 1 10 | 0.57 10.0116} 4.2 | 0.52 0.0110} 4.1 | 0.42 |0.0104 | 3.7 2 10 | 0.57 10.0132] 3.7 | 0.62 |0.0123} 4.4 | 0.49 /0.0115 | 3.9 II 3 10 | 0.62 |0.0126} 4.3 | 0.58 |0.0120} 4.2 | 0.46 |0.0113 | 3.7 Average ..| 0.59 |0.0125| 4.1 | 0.57 |0.0118| 4.2 | 0.46 |0.0111 | 3.8 *4 worms. 432 GEORGE DELWIN ALLEN time 12 tests of the oxygen consumption were made, each of about 46 hours’ duration. Column 6 shows a steady decline in the average amount of oxygen consumed by the 8 worms in each bottle from 0.105 to 0.037 cc. per 24 hours. In figure 4 the oxygen consumption by the worms during the 34 days of observation, is shown as the control for a TABLE 4 Showing rate of oxygen consumption by Planaria maculata during starvation. Worms starving for several weeks preceding first test and during the experiment; 8 worms in each bottle. One cubic centimeter thiosulphate equals 0.1766 cc. oxygen atN.T.P. Worms weighed November 20, 27, December 1, 4, 11, 18, 25. Average weight for each test period determined by interpolation. Control for table 8. See figures 4 and 5 (1) (2) (3) (4) (5) (6) (7) | (8) | (9) | (10) jan 1 Jag | aaa g ap |Sa_| RRS 26 A Bo | ial oe ile OXYGEN CONSUMED PER ° a |mOnlaoal @a GRAM BODY WEIGHT is a ® mae) PAS) of é q PER 24 HOURS a =o a mo Aan< io < ) ma a Ro = 5 oo 8 Fi 6|| Goh 5 Bm p g° B A?) aaa DATE OF TEST a a BR |o, ela, @| gee 2 mm of | 220! 2aRr an I fe E Z, ~*a|°S5|/Ss"!| Ome se P rs z o -2| 224/224) ec 8 Individual determi- 2 & a BEE ROG See Boo nations s y 3 4220|5F5) Fal a 5 a a ° ° 2 < cc cc. A ce. cc. ce. ce. ce. hours Cz thio. | thio. lorygen grams |ory- ory gen orygen | oxygen November 20-22..../46.17} 19.8-20.3] 4.58) 1.11]0. 105|0.0152'5.516.1 |9.0(?)|6.9 November 24-26... ./48.00} 20.0-20.6) 4.47| 0.93|0.085/0.0134|7.0155.6 (6.2 |6.3 December 1- 3..../45.92} 20.0-20.3] 4.55) 0.79/0.075|0.0108]7.1/8.3 |5.9 {7.0 December 4- 6..../46.15/20.0+00.1] 4.29] 0.72/0.068/0.0099/6.7/8.6 {6.0 {6.9 December 6-— 8..../46.13} 20.0-20.2| 4.02) 0.63/0.060\0.0093/5.6|7.1 |6.5 6.4 December 8-10....|46.00) 19.8-20.1} 4.10) 0.64/0.061\0.0089)/6.5)/7.2 3 December 11-13....|46.17) 20.1-20.3] 4.28] 0.57|0.05410.0081/6.3/7.2 (6.5 (6.7 December 13-15... .|46.25) 20.0-20.2| 4.21) 0.46|0.044/0.0075/6.1|5.9 : December 15-17....|46.05| 20.0-20.3} 4.25) 0.58/0.055/0.0069/7.5)/9.2(?)|7.5 [8.0 December 18-20... ./46.17| 20.0-20.3} 4.25) 0.45/0.043|0.0061/6.6/7.5 |7.0 {7.0 December 20-22... .|46.05} 20.3-18.7| 4.31] 0.50/0.048/0.0058/8.0)9.5(?)|7.6 |8.2 December 22-24... .|51.23} 19.9-20.1] 4.34) 0.43/0.037/0.0054/6.3/6.5 |7.6 (6.8 feeding experiment. Column 7, table 4, shows a similar loss of average weight from 0.0152 to 0.0054 gram per 8 worms. Column 11 shows a fairly uniform rate of oxygen consumption of 6.5 to 7.0 cc. per gram weight during the 34 days of starvation. These last figures are repre- sented graphically in figure 5. Columns 8, 9 and 10 show the varia- STUDIES ON RESPIRATORY METABOLISM IN PLANARIA 433 tion in determinations of the individual bottles which indicates the limits of error in the experiment. Table 5 gives similar observations upon starving Planaria maculata during a period of 27 days. The worms were starved 15 days previous TABLE 5 Showing rate of oxygen consumption by Planaria maculata during starvation. Worms 10 to 13 mm. in length on January 8; starving for 15 days previous to the first test and during the experiment; 8 worms in each bottle. Weighed January 12, 14, 15, February 5 and 13. One cubic centimeter thiosulphate equals 0.1698 cc. oxygenatN.T.P. See figure 9. For further data on control, see table 12 ) @) @) ®|@o] © | @ | @ | | (10) av [aq | Bs a F 8 2 & ls OXYGEN CONSUMED PER S 7) age ie GRAM BODY WEIGHT be So adel eS PER 24 HOURS a a < Bog co & re Sis et DATE OF TEST 2 | pemMpERATURE|*®q |28e] 2S & o> | 4240] BE 6 eae aioe Si a | Za< = | Individual determi-| Aver- Ey MEE) Boh) me nations age o Z off io} z yy) wo 0.03 r= = > < s x 0.02 © © 0.0.) 004 S 0.0 5 12 19 26 2 Os 16 JULY AUG. Fig. 3. Curves show decrease in oxygen consumption by Planaria agilis com- pared with decrease in weight during 6 weeks of starvation. Abscissas, time in weeks indicated by dates. Ordinates at the left, weight of 5 worms in grams. Ordinates at the right, oxygen consumption by 5 worms per 24 hours in ec. oxygen. Broken line represents average weight of three sets of worms weighed once a week. Solid line represents average oxygen consumption by the same three sets of worms, three tests made each week. See table 7 and figure 2. distinction between the early period of a few days of starvation, during which food reserves from the last feedings are effective in increasing oxygen consumption, and the later period of several weeks, during which the rate of oxidations is uniform, is very important. In the first place, the fact that the rate of oxidations is uniform during a long period of starvation (6 weeks) will serve as an important basis for the study of respiratory metabolism in these forms. In the second place, the fact that food reserves alter the respiratory metabolism for several days at the beginning of starvation makes this period unsuited for such studies. 438 GEORGE DELWIN ALLEN According to the experiments above and those in the following section on oxidations after feeding, this preliminary period during which food reserves alter the respiratory metabolism may last for a number of days in P. maculata and P. agilis. In any case before the “basal” or “standard metabolism” has been reached, the rate of oxidations is not a proper basis for comparisons. The respiratory metabolism during extreme starvation, when the body has been reduced to a minute fraction of the original weight by starvation alone unaccompanied by fission, has not been studied, and the statements above are not intended to include such later stages. OXIDATIONS AFTER FEEDING It is well known that the ingestion of food results in increased oxida- tions and heat production in higher animals. Planaria can take in at one meal a very large amount of suitable food material, such as boiled egg yolk, clotted blood or beef liver. Several experiments show that such a meal results in a great increase in the oxygen consumption. Table 8 shows an experiment in which P. maculata were fed clotted blood. Columns 4 and 5 give the oxygen consumption of the control worms which were starving throughout the experiment. The control is described in more detail in table 4. The experimental worms were fed blood clots on December 3. Column 7, table 8, shows that the actual amount of oxygen absorbed, which was decreasing progressively before feeding, doubled in the first test following the meal, then declined rap- idly, and later more slowly. Figure 4 shows these relations. Column 8, table 8, shows that the worms ingested about 60 per cent of their own weight at this meal. When the rate of oxygen consumption per gram body weight was calculated as in column 12, it was found to rise suddenly from 6.7 to 9.6 ce. oxygen per gram weight and then to fall rapidly to its former level and to remain fairly constant as shown in figure 5. In this calculation the food in the digestive tract is included in the total body weight, thus making the rate of oxygen consumption appear less than its true value. If the weight of food is subtracted from the total body weight for the first test period following the meal, the rate of oxygen absorption per gram of empty body weight becomes 16.5 ce., as Shown in table 8, column 12. Upon this basis of calculation, then, the ingestion of food resulted in an immediate increase in the rate of oxygen consumption of over 140 per cent. , ‘qys1am Apo [%jO} ULOIZ P9}OVAZGNS POOF pojsosur Jo VYBIOA > or) ae, eS 19 8g ¢800°0 | 870°0 2¢9°0 89 ZSO°O: 0 OGs6" GT eGGe TS ae ¥E-GE LoquIs9 aC] 89 a9 to 4 89 6600°0 | 490°0 L9°0 G8 SOO) 2° 8i-2 02 S007 4) 2 ae 66-0ZG IOQuIod9C] 89 ORS PL v9 6600°0 | &90°0 99°0 02 &70'0 |€'0c-0'02 ZT'9F | °°’ 0G-8T Jequiedeq g°9 6S 69 69 O110'0 | 1L0°0 G20 O'8 20°06 0G-0'0g) "S0°9F | = = LI-GT taquredeqd 69 £9 v9 19 8110°0 | 740°0 $20 8g VHO'O |6-02-0 OcieSaoM | eo ST-€T toquiev0q 8°9 r9 VL 69 9¢T0°0 | 980°0 160 LOy—- 000-8 0C-E 06 |oLTe OF, 1 ex SI-IT toquresaq] ae) OL 62 OZ I¥10'0 | 9010 OL T 89 190° 0-—|1 02-8°61|00°97 || = “0-8 Jequisdeq 48 18 £6 06 §910'0 | Y§1'0 We V9 090°0 |S°O0c=0 Ociecl SF =) = = 8 -9 Joquiov0d 96 86 9°6 £6 99100 | 6910 £9" 1 69 SOO OL LOO OC EsIsok 1) - sae 9 -p soquis00q #(9°9T) |\x(L°L0) |e(L°ST) |e(2°ST) |¥(7070°0 § laquis09q _$}O]9 poolq poy SuLIOM [VJUOUITIEdxG 4-9 v9 OL 39 &110°0 | 9L0°0 08 0 OL £200 |& OCD OC|sc6 SP} = = Soar ee 49 6¢ SL $9 #6100 | 060°0 660 & 9 G80°0 |9°02-0'0¢| 00'8F | Vogvore daeoe oN r9 6¢ 9 T9 £9100 | 960°0 00'T 6°9 SOLO |S OC 8 O1IPZIE OY Si- 0 sei GG UG sequIasON uabhixo *99 | uablixo “99 | uabixo *99 | wabhixo “99 smoiB uabhzo "99 | °0242°99 | uabhxo ‘99 | uabhixo*99 HOY sunoy OBvIOAY OBVIOAY asBiaAy | odvi0Ay “sunoy ; me “sunoy aSUIIAY SUOIPVULULIOJOpP [BNPAIpuy VDBIDAY ‘9]}| FZ 10d a[9 geen red vate pz ted 914 stnomg oti] ur sumow | SUOM | we | TS taom OTSA | gour dq | 82U3 AA | sod uo | Oia iK aor JO F819 spears pewnsuoo|-dunsuoo | 8 244 “44 au OLY ; ; F SINOY FZ aod qQUSIOM peunsuoo waFAXGQ uasAxQ peulnsuo09 -UgdWaL I8SaL JO L8aL dO ALVa Apoq wieis 19d uorduinsuos uasAxG— uasAXQ uasAxQ—) HLONGT INGAWNINAdxXT WIOHM § UAANAOAG SLOTIO GOOTH Gat SHUOM ‘INAWINAdXE HOD OOUHL ONIAUVIS SNUOM TOULNOD STUDIES ON RESPIRATORY METABOLISM IN PLANARIA (1) | an | (on) | 6) | @ | | (9) | (¢) | () () 3) a) "Y 2790} 998 ‘s]04]U09 UO DIDP LaYyIINf LOY *G pun F saunbyf aay ‘dL’ N 1 Uabhixo +99 99410 = ayoydjnsor) sajyauyuaa a1qna aug) “Gg pun gt ‘TTY ‘g ‘T saquasag ‘Le ‘0g saquiaao Ny paybra jy “paf OU SULOM JOU “gE Laquiaveg UO s}0]9 poo]g paf susom Jo PUIUIWAde °217}09. Yyova UL susoM g 4897 18.uuf 24) Burparaad syaan poLaaas of paf jou suso4, *poo7g paz}0j9 Buarpaaf sazfo vyojnovu visoun)g fiq uoydunsuods uabhixo ur aspasaur yoasb Burnoysy 8 WIAVL ee 440 GEORGE DELWIN ALLEN Table 9 gives similar data for an experiment in which P. agilis were fed beef liver. Data for the control worms, which were starving through- out the experiment, are given in columns 4 and 5, and more fully in table 7. After feeding upon liver, July 20, the amount of oxygen ab- sorbed by the experimental worms increased from 0.096 to 0.167 ce. per 5 worms per 24 hours, column 7, table 9. The body weight in- 0.1 6 0.14 0.12 0.10 0.08 OXYGEN 0.0 6 (GRC 0.0 20 27 4 1] 18 25 NOV. DEC. Fig. 4. Curves show decrease in oxygen consumption by starving Planaria maculata, and increase in oxygen consumption after feeding. Abscissas, time in weeks indicated by dates. Ordinates, cc. oxygen consumed by 8 worms in 24 hours. Broken line represents average of three sets of worms, starving through- out the experiment. Solid line represents average of three sets of worms, fed once on December 3. The arrow indicates when the experimental worms were fed. See table 8. creased from 0.0276 to 0.0353 gram per 5 worms and the rate of oxygen consumption per gram of total body weight, including the ingested food, increased from 3.5 to 4.7 ce., column 12. Deducting the weight of food, the rate of oxygen consumption per gram of empty body weight becomes 6.4 cc. for the first test after feeding, an increase of over 80 per cent. These relations are shown graphically in figures 6and 7. In- spection of these curves shows that the oxidations rise suddenly with STUDIES ON RESPIRATORY METABOLISM IN PLANARIA 44] the taking in of food and decline rapidly during the next week or ten days to a constant level. In figure 6, the curve of the absolute amount of oxygen consumed by the experimental worms ran parallel to the con- trol for two weeks preceding the meal. After feeding, it rose sharply, then declined rapidly during the next 10 to 12 days, and then contin- ued parallel with the control, but at a relatively higher position. This might indicate one of two things, either that the meal had resulted in a certain amount of growth so that the animals which were formerly smaller than the controls became slightly larger, or that the meal re- z w& Oo 2 S 2 1S) 20 27 4 il 18 25 NOV. DEC. Fig. 5. Curves show practically constant rate of oxygen consumption by Pla- naria. maculata during starvation and increase in rate of oxygen consumption af- ter feeding. Abscissas represent time in weeks indicated by dates. Ordinates represent rate of oxygen consumption in cc. of oxygen per gram total body weight per 24 hours. Broken line represents the average of three sets of worms starving throughout the experiment. Solid line represents the average of three sets of worms fed once on December 3 (time of feeding indicated by the arrow). * rep- resents the rate of oxygen consumption by fed worms in cc. oxygen per gram empty body weight (weight of body if no food had been ingested) per 24 hours. See table 8 and figure 4. sulted in a permanent increase in the speed of oxidations. Figure7 and tables 9 and 7 indicate that the former interpretation is correct. A comparison of the average weights given in table 9, column 8, and table 7, column 7, shows that the experimental worms did weigh less than the control worms. during the two weeks before the feeding, but that after feeding they did not become reduced again to the weight of the controls. Moreover, figure 7 shows that after August 1 the rate of oxygen consumption by the two lots of worms per gram total body weight ran parallel for 15 days, or till the end of the experiment. THE AMERICAN JOURNAL OF PHYSIOLOGY, VOL. 49, NO. 3 46 8's Ls 8's £4600 | GOI 0 90°T ee 6800. 1c02-9 OTOL oy 4) = "6 S-2@ Ayn Ted Uv O'P GP 6860°0 | 8IT 0 at e€ G60°0 |0°02-2'6T] OO'@P | 9%-HS ATE 97 OV oP LY 86¢0°0 | £&1°0 LET ans ZOL'O |2°61-0°02| OS Sh | He-VB Aloe bel OV aiey, I £960°0 | 4910 oot €'& POLO |0°02-9'6T) Gath f° BeOS ATne «(7'9) |u(L°9) |e(T'9) fa(P°9) |x (6980°0) 02 A[NE A9AT] Jood pay SuI0M [By UoWUOdxoy g°¢ o.G ve Ge - 9480°0 | 960°0 66°0 eé EURO NG Oley iOC 00 RSs) a Be ee | 6I-L1 Arne g's i fic ve 4860°0 | 660°0 60°T ve QUE .O Shes OGROOEG TSS ae eS L1-Gt Ayne oS Vs VE 9°€ 86¢0°0 | G0T'0 60°T ae) TEDO) WP WleGtOCiea le Sy ES ee ee cT-er Arne 7 8 & L$ 8's 6°E &1&0°0 | 0610 ¥G'T 9°§ TELAO) 46. 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This result explains why the oxidations in well-fed worms decrease during the first stages of starvation (see expers. 2 and 7 and figs. 3 and 7). OXYGEN 5 12 19 26 2 9 16 JULY AUG. Fig. 6. Curves show decrease in oxygen consumption by Planaria agilis during starvation and increase after feeding. Abscissas represent time in weeks, indi- cated by dates. Ordinates represent ec. oxygen consumed by 5 worms per 24 hours. Broken line represents the average of three sets of worms starving throughout the experiment. Solid line represents the average of three sets of worms fed once on July 20 (time of feeding indicated by the arrow). See table 9. OXIDATIONS IN WORMS OF DIFFERENT SIZE The rate of respiratory metabolism or heat production in higher ani- mals is commonly said to decrease with increasing size and age of the body. It is obvious that a larger animal will use more oxygen, give off more carbon dioxide and liberate more heat than a smaller animal of the same species under the same conditions. In order to make any comparison of the rates of respiratory exchange or heat production in STUDIES ON RESPIRATORY METABOLISM IN PLANARIA 445 the two animals, it is necessary to calculate the respiratory metabolism with reference to some common basis such as a unit of weight or surface area. It is understood that such comparisons should be made under standard conditions of a, fasting; b, uniform temperature; and c, mus- cular rest. But it should be distinctly kept in mind that when animals of different size and age are compared in this way a difference in the rates of respiratory metabolism may or may not mean that comparable - OXYGEN ~ I (Ce (Ge N 5 12 19 26 2 9 16 JULY AUG. Fig. 7. Curves show constant rate of oxygen consumption by Planaria agilis during starvation and increase in rate of oxygen consumption after feeding. Abscissas represent time in weeks, indicated by dates. Ordinates represent rate of oxygen consumption in cc. oxygen per gram total body weight per 24 hours. Broken line represents the average of three sets of worms starving throughout the experiment. The solid line represents the average of three sets of worms fed once on July 20 (time of feeding indicated by the arrow). * represents the rate of oxygen consumption by the fed worms in cc. oxygen per gram empty body weight (weight of body if no food had been ingested) per 24 hours. See table 9 and figure 6. cells in the two animals have inherently different rates of oxidation. Different opinions are held regarding the cellular rates of oxidation in these cases (see Benedict, 22). The observation is merely that the total amounts of heat produced are not proportional to the weights or surface areas of the animals. It is well known that among warm-blood animals the smaller animal produces more heat in proportion to its weight than the larger individual. 446 GEORGE DELWIN ALLEN Various authors since Rubner (21) have presented evidence that the re- spiratory metabolism of warm-blooded animals, at least, is proportional to the area of the surface of the body. The respiratory metabolism is often calculated per unit of body surface with the idea of eliminating size differences when other factors are being compared. Why the heat pro- duction should be proportional to the area of the skin is not entirely clear. In a general way, the proportionality between the rate of heat produc- tion and the area of the radiating surface is of adaptive value to ani- mals which must maintain constant body temperature, but this consid- eration does not explain what mechanism regulates the rate of energy production in the individual. Apparently it is not simply an accommo- dation of the heat production to the rate of heat loss (see Krogh (13, pp. 133-140) and Lusk (10, p. 120) ). Benedict (22), (23) has ob- jected to the practice of computing metabolism in terms of the unit of surface and has collected data from a large number of normal controls in human metabolism experiments to show that metabolism, calculated per unit of area of the body surface, gives large variations. Some of the variation, may be traced, apparently, to errors in the prevailing method of estimating the surface area. The area of the surface of an animal is not easily measured. It is usually estimated from the weight by means of the formula of Meeh (24) which is based on the law that surfaces of similar solids are proportional to the two-thirds power of their volumes. The bodies of fat and thin persons are not geometrically similar, however, and this formula is known to give large errors in com- puting the skin areas in such cases. Upon the basis of careful meas- urements of the areas of the skin of individuals of very different propor- tions, Du Bois and Du Bois (25), (26), have derived a “linear” and a “height-weight”’ formula which give the surface area with a maximum error of only 5 per cent in contrast with the average error of 16 per cent and a maximum error of 36 per cent with the Meeh formula. The metabolism seems to be more nearly proportional to the skin area as computed with the new formula than with the older one (27). Among adult mammals, then, the individual of smaller size produces more heat in proportion to its weight than the larger individual, and whatever may be the reason, the amount of the difference seems to be in accord- ance with the “surfacelaw.”’ This is true of the persons of the same age. When individuals of different ages are compared, the difference in the rate of heat production per unit of weight does not seem to follow the surface law so closely. The rate of heat production per square meter of surface is higher in youth and lower in old age than in middle life (28), STUDIES ON RESPIRATORY METABOLISM IN PLANARIA 447 (29), (27) and (10, p. 128). On the other hand the metabolism of in- fants per square meter is less than that of older children. That of babies in the first month of life is lowest (12, p. 117); (80), (31), (82), (29, charts 1 to 3). But Bohr’s (33) measurements of the respiratory exchanges of pregnant guinea pigs with circulation through the umbilical cord suspended, indicate a rate of oxidations in the embryo per unit of weight not far different from that of the parent. Bohr and Hasselbalch (34) found that the carbon dioxide production by the developing chick embryo from the ninth to the eighteenth days was closely proportional to the weight of the embryo. These observations upon infants and em- bryos serve to emphasize the fact that the interpretation of differences in rate of respiratory metabolism in warm-blooded animals in relation to size and age, whether calculated per unit of surface or of weight, in- volves questions of the constitution and functional conditions of the body. While the metabolism studies on warm-blooded animals are commonly cited to show that the rate of oxidations is higher in animals of smaller size and in younger animals, as a matter of fact the warm blooded animals are very unsuited to the critical study of these questions. Turning to the cold-blooded animals, observations on the rate of respi- ratory metabolism in relation to size and age are very inadequate. It may be noted at the outset that there is no reason for supposing that metabolism in these animals, of widely different structural organization, should follow the “surface law.” It has been shown definitely by Morgulis (36) that this relationship does not exist in the flounder. He finds, rather, that as size of the body increases, the oxygen consump- tion per unit of body surface increases, and that per unit of body weight decreases, while after removal of the fins the oxygen consump- tion is proportional to the mass. Buytendijk (quoted by Montuori (35, p. 216)) and Montuori (35, p. 216) both report that Seyllium of smaller size consume more oxygen per kilogram hour than those of larger size. Observations on the rate of respiratory metabolism in invertebrates in relation to size and age are conflicting but this may be due to unsat- isfactory experimental methods. Buytendijk (as quoted by Mon- tuori (35, p. 216) ) measured the oxygen consumption by Scorpaena, Octopus and Echinus in relation to body size, and Montuori (35) at- tempted a survey of these relations in 80 different kinds of marine ani- mals belonging to the coelenterates, echinoderms, worms, crustaceans and fish. In the determinations on some species, the oxygen consump- 448° GEORGE DELWIN ALLEN tion per unit of weight was greater in the animals of smaller size than in those of larger size. In other series the reverse relationship was re- corded, and in still other series the results were highly variable. These results may mean that standard conditions were not maintained in all cases, that the individuals compared were not strictly comparable or that in some cases the forms chosen were unsuited in behavior and respir- atory habits to the solution of the question. Each species would re- quire more critical individual study to determine the reasons for the irregularities. The conclusion of Montuori that “the consumption of oxygen, calculated per unit of weight, is, in general, absolutely inde- pendent of the dimensions of the animal,’ hardly seems justified from such highly variable determinations. The subject requires much more careful quantitative work under more definitely controlled conditions than has hitherto been done, before any conclusions of general applica- tion can be drawn. Some forms of animals, because of inconstant be- havior, are quite unsuited as experimental material. Careful measurements of the rate of respiratory metabolism per unit of weight in lower cold-blooded animals have indicated, however, that there is a decrease in rate of oxidations as the size of the body in- creases. Bounhiol (37) found this relationship in the oxygen consump- tion of annelids of different size, and Miss Wolf, in this laboratory, has found it in the leech, crayfish, branchipus, May-fly nymph and Stone- fly nymph, under very conclusive experimental conditions. The num- ber of determinations, made by the writer, of the rate of oxygen con- sumption by Planaria in various kinds of experiments, makes it certain that consistent results can be obtained for this form with the methods used. Various incidental observations in the course of these experi- ments point to the fact that smaller worms absorb more oxygen in pro- portion to their weight than larger worms, and the following systematic experiments show it very clearly. Table 10 gives comparative measurements of the oxygen consump- tion by P. agilis of five different sizes. Planaria differ considerably in body proportions, the region posterior to the pharynx being much longer in some individuals than in others. To make worms as nearly uniform as possible, all except the smallest, set I, were cut at the plane of normal fission, a short distance posterior to the mouth. This was done 21 days before the determinations of oxygen consumption were made. All worms were without food for 22 days previous to the ex- periment. At the time of the respiration test, the worms of set I aver- aged 6.08 mm. in length, worms of set II, 8.4 mm., those of set III,11.8, STUDIES ON RESPIRATORY METABOLISM IN PLANARIA 449 TABLE 10 Showing decrease in the rate of oxygen consumption by Planaria agilis with increase in size of the body. Worms starving for 22 days preceding the experiment and dur- ing the experiment. Tails removed at the fission plane 21 days before the experi- ment of all sets except set I, the smallest worms. Test period of 24 hours’ duration. Temperature 19.6°C. + 0.01. Capacity of bottles 130 cc. Correction for 4 cc. of water displayed by rods and reagents, multiply by 1.032. One cubic centimeter thiosulphate = 0.1738 cc. oxygen at N. T. P. Worms weighed 6 hours after the test. See figure 8 PART SET | BOTTLE : BLANKS cc, thio. average - eee if 4.17 “4 a q A j|aBe| 2 4.18 4.18 faa) Om aa . ay 3 4.20 (1) (2) (3) (4) (5) (6) (7) (8) | (9) a S E Bee pene OXYGEN z & Q g S 3 CONSUMED PER WEIGHT pigs onic ae a ao = ae 10 worms PER 10 WORMS peste ald ra ea |e g Ea en ae PER 24 HOURS a6 SE oa < a ° mm, | cc. thio.| cc. thio. denen average| grams | average een average 1 | 6.038 | 20 | 0.33 |0.0295 0.0069 4.3 I 2 | 6.13 | 20 | 0.44 |0.0394/0.0349|0.0073/0.0070| 5.4 | 4.9 3 | 6.08 | 20 | 0.89 |0.0349 0.0069 5.1 1 8.4] 15 | 0.68 |0.0812 0.0178 4.6 Il 2 8.4 | 15 | 0.68 |0.0812|0.0792'0.0179|0.0175| 4.5 | 4.6 3 8.4 | 15 | 0.63 |0.0753 0.0168 4.4 1 } i.7 |. 10 | 0.89 |0.1595 0.0437 3.6 B Ill 2 ab aee 10 | 0.97 |0.1738)0.1678\0.0469|0.0451) 3.7 3.7 See One LO O0r9a 1021702 0.0448 3.8 1 | 14.8 6 | 0.92 0.2748 0.0832 3.3 IV 2, | 14.0 6 | 0.84 |0.2509/0.255910.0772|0.0769| 3.3 | 3.3 3 12.9 6 | 0.81 |0.2419 0.0702 3.4 1 17.8 4 | 1.04 |0.4659 0.1568 3.0 V 2 17.9 + 1.08 |0.4838)0. 4674/0.1603|0.1551) 3.0] 3.0 3) | L725 4 | 1.01 |0.4525 0.1483 3.0 450 GEORGE DELWIN ALLEN those of a set IV, 13.9 mm. and those of set V, 17.7 mm., as shown in column 1. Length, however, is no satisfactory measure of size even though precautions are taken, as described above, to make the worms as nearly comparable as possible in body proportions. The weights, as given in columns 6 and 7, ranged from 0.0070 to 0.1551 gram per 10 worms. The largest weighed twenty-two times as much as the small- est. Because of this great difference in size, the number of individuals in each bottle was varied so as to make the amounts of oxygen absorbed in each bottle nearly equivalent. The average amount of oxygen con- sumed per gram body weight per 24 hours decreased from 4.9 ce. in the OXYGE WEIGHT GRAM PER 0.0 0.0 5 0.10 0.1.5 GRAMS WEIGHT PER 10 WORMS Fig. 8. Curve shows decrease in rate of oxygen consumption by Planaria agilis with increase in size of the body. Abscissas represent weight per 10 worms in grams. Ordinates represent rate of oxygen consumption in cc. oxygen per gram body weight per 24 hours. Each point on the curve represents the average of three sets of worms. See table 10. smallest worms to 3.0 ec. in the largest. All worms were tested simul- taneously under identical conditions. Independent determinations were made for three different bottles of worms of each size, and column 8 shows that, with one exception, there was no overlapping among the individual determinations. Set I, bottle 1, gave a very low value. The titration reading of thiosulphate, column 3, was only 0.33 ce. in this case. It should be remembered that a difference of one drop in titration would make a difference of 0.06 cc., and that titration values as small as this are less accurate than larger ones. This experiment shows, therefore, that the rate of oxidations decreased as the size of the STUDIES ON RESPIRATORY METABOLISM IN PLANARIA 451 worms increased. These results are shown in figure 8 where the amount of oxygen consumed per gram body weight per 24 hours at 20°C. is plotted against body weight per 10 worms. This curve shows at a glance that the rate of oxidations decreases with increasing size, and that the de- crease in oxidations is not directly proportional to the increase in weight. Among smaller worms, these differences are greater than among larger worms. Most of the difference was between worms less than 0.08 gram weight per 10 individuals. Worms of twice that size showed little further decrease in their oxidations. It might be thought that the differences in the rates of oxidations among Planaria of different sizes, recorded in table 10, might be due to differences in activity. Was there a graduated difference in activity among the worms of different sizes during the respiration test? This question was tested by removing the heads of worms of different sizes so as to eliminate practically all locomotion. Worms of three different sizes were used, table 11. Those of each size were divided into two sets of three bottles each. A control test was made in which all worms were uncut and normal. Columns 5 and 6 show that, in each case, the two sets of worms of the same size had the same rate of oxygen consump- tion, and that the differences between the different sizes confirm the previous experiment, table 10. Before the second test, table 11, the heads were removed from the worms in one set of each size. In this test the normal worms, column 10, duplicated the rates of oxygen con- sumption given in the previous control test, while the headless worms in each case used less oxygen, 85 to 90 per cent of the normal. In com- paring the headless worms of the three sizes, however, the size differences remain. The headless small worms used 3.9 ec. of oxygen per gram weight per 24 hours, the medium-sized worms, 3.3 cc., and the large worms, 2.8 cc. We conclude, therefore, that the rate of oxidations in Planaria decreases with increasing total body weight, and that this de- crease is not accounted for by difference in locomotion. The worms of sets II, III and V of table 10 were used as sets II a, III a and V a, respectively, of table 11. Since the worms were weighed for each test, these experiments constitute, in reality, three independent determinations of the normal rate of oxygen consumption by these _ worms, in relation to size. The three determinations gave the same re- sults. The smaller worms used 4.5, 4.5 and 4.6 ec. of oxygen per gram body weight per 24 hours in the three determinations. The medium- sized worms used 3.7, 3.6 and 3.7 cc. of oxygen, and the larger worms 3.0, 3.1 and 3.1 cc. of oxygen, respectively, in the successive determinations. GEORGE DELWIN ALLEN 452 8'€ | P4100} 2&°0 a 9610°0 | 90 ST € SsoppvoH | 6°& OF | 2100} &F 0 Bt 0g 9120°0 | 19°0 a Teas G q O'F | S810°0| TO oP 6020'0 | €9°0 “iit i Il a 9F | 60c0°0 | #9°0 vv €€20'0 | 29°0 ST € [BULION | 99°F Gv | 26000} €&9°0 7 ev L820'0 | 249°0 ST UCGSsi Sc 8 O'S | 8100; Tg°0 OV G610'0 | ¥#9°0 ST i abnuaiy \wabhixo’20) swvub ‘01g (00 | abvuvan | uabfixo’00| swoJb *0uy} **99 ssa'lavaH SU NOH FZ gle ea ae SUNOH FZ oe eee GILLOA | AZIS HDUVT ; udd LHDIaM AGO NISWUOM | Udd LHDIGM AGO 5 NISWUOM | HOVGO NI | HO WO.aaW tO OAL. | KVEO Ua NOM eo. | Sansa wvup uganxow |NESVNOM| aut xa |swuoM 40) ‘vIviKS ~dWOSNOO NGDAXO} Tonia ay Serene -dNWOSNOO NADAXO CHO TaM corm negoe UAHWOAN | FO SNKUOM (11) (or) | @ | @) (2) (9) (¢) (¥) (€) (2) (1) | Sh? LEP v quosord eV P CV P € . : SUlLIOM OU wt Shp cr eh z See bi Wwe Se’? 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Burnoy ¥ Tl ATAVL 453 RESPIRATORY METABOLISM IN PLANARIA LinGe | ROCCOLON S200 67% O8g0'0 | +6°0 v € Ssa]poaHT | 8'@ 0€ | 28700} T8°0 0°s (ts 9¢¢0'0 | §6°0 P o3IB'T 6 q LG | €tS0°0 | 92°0 0's 1990°0 | ¢6°0 14 T A Tag escs0i0) |= c6.0 Gis 87g0' 0} 26°0 y € [BULION | T'S T’€ | 1990°0 | 96°0 ts T's Osso'0 | TO'T i OBIT 6 B 2 T’€ | Zg90°0 | ¥6°0 (ets 6¢90'0 | 96°0 i I! [o) ra | 2 os | $2800} 89°0 Dts Frr0 0 | £6°0 OT ‘S A Ssa]pva HT | &'s T€ | 4280°0 | ¢9°0 8°S Lies ¥rF0'0} §6°0 OT UMTpsy}Ay G q =) 9°¢€ | 21800)] 90 OM 7 824800 | S8°0 OT T a Iil 2S, aecSeOLO = Ge. O 9°8 €070'0 | 280 OT € [BUlION | 218 Gc¢€ | 80700] S80 9°§ 9°S €crFO0'0 | 98°0 OL UMTpofT G B 6°€ | S880°0 | +8°0 MAS; T660'0 | 280 OT T 454 GEORGE DELWIN ALLEN While it is clear that larger Planaria use less oxygen in proportion to their weight than smaller ones, it is not certain that this difference is to be associated with age or senescence of protoplasm. In the case of man, it is commonly supposed that there is a decrease in the rate of oxidations, associated with age, apart from changes in the oxidations which may be associated with alterations in the size of the body. Such a distinction is not apparent in the data concerning the rate of respira- tory metabolism in Planaria. It may be convenient to call a “full- grown” Planarian ‘‘old” in comparison with a “half-grown’”’ individ- ual, but it should be remembered that Planaria of the species dealt with in this discussion, after they have attained the more or less variable maxi- mum size for the species, are not known to die of old age. Old age in man is not synonymous with the attainment of a maximum (“‘adult’’) body size. We have no evidence, as yet, that a Planarian of constant size becomes senescent or suffers a reduction in the rate of oxidations. The statement that the rate of oxidations per unit of body weight is higher in small Planaria than in larger ones of the same species, as- sumes that the worms are compared in the same condition of nutrition, namely that they have been starved long enough to pass the accelera- tive effects of previous feedings, and that the differences in size are not due to differences in length of starvation. Within the limits of the experiments which have been performed on starvation we have con- cluded that the rate of oxidations continues practically constant after the early stages. In figure 3, starving Planaria weighed 0.0720 gram per 10 worms on July 12, by which time the accelerative effects of previous feeding had disappeared, and these same worms were reduced in weight to 0.0360 gram per 10 worms on August 16 at the end of the last respiration test. Figure 8 shows that worms of these two weights and of equal starvation differed in oxygen consump- tion by about 0.5 cc. oxygen per gram body weight per 24 hours. Such a change in the respiratory exchange of the starving worms was not found (see fig. 7). In this case the worms were reduced in weight to one- half of the original. The respiratory exchange in more extreme starva- tion, with reduction in size to a minute fraction of the original has not been studied. OXIDATIONS DURING REGENERATION The species of Planaria employed in these studies reproduce more commonly by agamic fission than by sexual processes. If the rate of oxidations decreases with increasing size of the body, as shown in the STUDIES ON RESPIRATORY METABOLISM IN PLANARIA 455 preceding section, then it follows that it should increase with regenera- tion of small pieces of large worms into complete small worms. Nat- ural fission results in two pieces of very unequal size and character. The anterior piece is much larger and retains the old head and body as far back as a level just posterior to the mouth. After regeneration it is essentially the original parent with a shorter tail but with little change in other proportions. On the other hand, the posterior piece is much smaller and undergoes profound reorganization into an animal with head and body of smaller proportions. Experiments show that the posterior piece undergoes considerable increase in rate of oxidations during regeneration while the anterior piece retains the original rate of oxidations of the parent practically unchanged. Table 12 records the results of a preliminary experiment in which P. maculata were cut at the normal fission plane and allowed to regenerate, the oxygen consumption of the anterior pieces, the posterior pieces and uncut control worms being followed for 24 days after the operation. Column 4 gives the oxygen consumption by the normal controls (see also table 5). In column 11 the average rate of oxygen consumption by the anterior pieces is seen to be almost equal to that of the normal con- trols throughout the period of regeneration. The rate of oxygen con- sumption by the posterior pieces, however, is considerably higher in each determination than that by the controls or that by the anterior pieces. These results are shown also in figure 9. In a second preliminary experiment, worms were cut Just posterior to the auricles, and allowed to regenerate new heads. Under these con- ditions they were not much reduced in size during the regeneration of the new head. These worms were more comparable, therefore, to the anterior pieces of the preceding experiment than to the posterior pieces. Table 13 shows that the worms regenerating their heads maintained a rate of oxidation practically equal to that of control normal worms for the period of observation, 17 days. These results are shown also in figure 10. Table 14 and figure 11 give a more complete series of determinations of the oxygen consumption by P. agilis during two weeks preceding and four weeks following experimental fission. The rate of oxygen consump- tion per gram body weight per 24 hours of normal worms ran very uni- form throughout the experiment, column 4. These normal worms have been discussed in connection with table 7. The experimental worms duplicated very closely the rate of oxygen consumption by the controls during two weeks preceding the operation, table 14, column 11. After cutting the experimental worms in two at the normal fission plane, the GEORGE DELWIN ALLEN 89 e°¢ UP OF 8°9 6'S oP ian 19 9 LY 9°F 8°9 G9 0's 0'¢ oF c'P uabhixo *99 | uabhxo ‘99 | uabhixo ‘92 | uabhixo ‘99 OBIOAY SUOIJBULULIOJOP [BNPLATpuy urei3 rod wor4yduInsu0d UaBAXO Jo 978 YY 1g P'S | $9000 | FEO | Hor1a780q Tey; Stan oe ea ey | te | ztt0'0| Gro ane ac of Pees . (€°02) Lg 09 | 8900°0| FF'0 | t0209280g oe oe ete. Meee LP Zp i eeto:0 |. 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The rate of oxygen absorption by the posterior pieces, however, rose gradually above the controls during regeneration. These posterior pieces reorganized during this period to form complete worms of smaller size than the controls or than the anterior pieces. The following notes indicate the progress of regeneration of the tail pieces. OXYGEN Cc (Sr 12 ES, 26 2 9 RACING: FIEND. Fig. 9. Curves show increase in the rate of oxygen consumption by Planaria maculata during regeneration of posterior pieces from experimental fission, and no increase, within the limits of error of the experiment, in the rate of oxygen consumption in anterior pieces. Abscissas represent time in weeks, indicated by dates. Ordinates represent the rate of oxygen consumption in ec. oxygen per gram body weight per 24 hours. The broken line represents the control, an aver- age of three sets of normal worms. The solid line represents the average of three sets of posterior pieces from experimental fission. The line of dashes represents the average of three sets of the anterior pieces from experimental fission of the same worms. Worms cut on January 15 (time of the operation indicated by the arrow). See table 12. July 20. Cut experimental worms across body a short distance posterior to the mouth. July 24. New head, wedge-shaped. Some locomotion after disturbance of dish. July 26. Auricles and eyes. Worms elongating. STUDIES ON RESPIRATORY METABOLISM IN PLANARIA 459 July 29. Auricles well developed but not full length. Heads appear white to the naked eye. tion rapid. August 2. Still white-headed. August §. Pigmentation of head still incomplete. Pigment appearing on head. TABLE 15 Inactive till prodded. Locomo- Worms more elongated. Showing no increase, within the limits of error of the experiment, in the rate of oxy- gen consumption by Planaria maculata during regeneration of the head. Worms 7 to 10 mm. long February 25; starving for 5 days preceding the first test and dur- ing the experiment; 10 worms in each bottle. worms just posterior to the auricles March 12. Control worms not cut. Heads cut off from the experimental Worms weighed March 2, 4, 11, 12, 18 and 30. One cubic centimeter thiosulphate = 0.1698 cc. oxygen at N.T.P. See figure 10. For further data on the controls, see table 6 (1) DATE OF TEST March 2- 4 War ehie: S=01.<.2 ssi «=: Maren %— 9.5. .5. 0. . March 9-11 March 12-14 March 14-16 March 16-18 March 19-21 March 21-29 (2) LENGTH OF TEST PERIOD (3) TEMPERA-~ TURE SG. 20.0-20.5 20.0-20.2 20.0-20.5 20.0-20.4 20.1-20.5 20.0-20.5 20.1-20.6 20.0- 20.0-20.5 (4) CONTROL gram hours per sumption by normal weight per 24 Average oxygen con- worms ce. oxygen 5.0 4.8 4.8 6.5 the worms in each Oxygen consumed by bottle. Average cc. thio. 0.77 0.80 0.74 0.72 0.51 0.52 0.46 0.34 1.39 © | ® | @ | ®| ® | a» EXPERIMENT es Rate of oxygen consumption a per gram body weight ES per 24 hours 23 sae oW 2 Zo Individual Aver- 402 determinations age 3.85 = Us tLe caged sanbn pean patton 0.0163} 5.0 | 5.1 | 4.4 | 4.8 0.0149) 4.9 | 5.2 | 4.8 | 5.0 0.0138) 4.7 | 5.1 | 4.5 | 4.8 0.0126) 5.1 | 5.3 | 5.4 | 6:3 Heads removed from experimental worms on arch 12 0.0092) 4.9 | 5.4 | 4.9 | 5.0 0.0084) 5.7 | 5.8 | 5.5 | 5.6 0.0077) 5.4 | 6.1 | 5.5 | 5.6 0.0067} 5.2 | 4.9 | 4.5 | 6.0 0.0056) 5.7 | 5.9 | 5.0 | 6.6 The smaller individuals in a population of Planaria usually result from This experiment shows that during the proc- fission and regeneration. esses of regeneration the higher rate of oxidation characteristic of smaller worms is attained. If the respiration of these small worms during growth were followed, undoubtedly a progressive decline in rate GEORGE DELWIN ALLEN 460 gS Ge && es TS10'0 | 6F°O °| 4024a;80g é ; ; : pcdeoie tas Beg oe Pree ice le cae ee area al socnvod tor sa €'§ |0°02-9'61| G22 2-02 Ane “oz Ang ‘ould UOISSY [VUIIOU 4B OM} UT 4NO SUIIOM [BJ UOTITIEd XAT &°& vs oe £& cOrO'0 | LET Sou Sis) 6 Oley 0c L000 Sh se = eee oS STL AT a as e& £& L1V0'0 | FFT 2(OTM VS. 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Ud 9spa.0Uur OU pun ‘uorssyf oL0If -4lD L9,{D piooz sorwajsod 942 ur uoynsauabas yn syibo piswunjg fiq uoydwnsuod uabhixo fo avs ay) Wr aspasour Burnoys FT ATA 6 py oF as oe ne ae a pe |2-61-9°61| oer [tt fee Ny 91-Fr snsny 4 ae ce ae A Be ee ee ag aegis Se mane fom ah Bs ey te no eo we ee lo-et-g-erl gpgp [ccc EOL ysnsny ; a ss! me a eee aa ne ye |eoepoz zogp [cote 6 <2 4sn3ny ) as ee Se a ope eo pea ye looc-eet| Loep [ccc -@ gensny i>) SBE Lae | Ee fer famwo| aro Jammy | oe leecol car prose -a-e aatey S) pee | 7 Se Seo ee own | eee Rad eee can M of [ey | se | 6 | sno) Gro fumed) | oe gray] onrgy fer re-6e Aine : oe Sere a me ee ba pers! ee feroao°er| orgy fee Rcestink = : eg ee ees ee eta nec e@ |oroz-2°61| OO fo oes Ate 8& GP L¢ 9S GFIO'O | ¥FS'0 rane PS 2s GISOS OG OSS Gis lies ans tie oe ane Neen ae $o-Go Aine 462 GEORGE DELWIN ALLEN of oxygen consumption would be found as the animals became larger. It is not very convenient to follow the oxidations in the same worms during growth, but it seems unnecessary to do so. Worms of different sizes selected from a laboratory stock of the same history, except as re- gards reproduction, and tested simultaneously under identical condi- tions, give more certain results. Such experiments are described in the preceding section. OXYGEN Cae: 2 9 16 23 30 MARCH Fig. 10. Curves show no increase, within the limits of error of the experi- ment, in the rate of oxygen consumption by Planaria maculata during regenera- tion of the head. Abscissas represent time in weeks, indicated by dates. Ordi- nates represent rate of oxygen consumption in ce. oxygen per gram total body weight per 24 hours. The broken line represents the control, an average of three sets of normal worms. The solid line represents the average of three sets of worms whose heads were cut off just posterior to the auricles on March 12 (time of the operation indicated by the arrow). See table 13. It should be clearly understood that these experiments upon regen- eration of Planaria are not advanced as evidence that the regeneration process, as such, or, more generally, that growth or morphogenesis, necessitates a higher rate of oxidation. In figure 11 the rate of oxygen consumption in the tails rose progressively during regeneration and did not show a fall with completion of the process. The higher rate at the end of the process is attributed to the new organization of the worm, i.e., to the result of the process, not to the process itself. At least the experimental data do not constitute a secure foundation for concluding otherwise. STUDIES ON RESPIRATORY METABOLISM IN PLANARIA 463 SUSCEPTIBILITY AS A MEASURE OF OXIDATIONS The susceptibility of Planaria and other animals to the toxic action of alcohol, potassium cyanide and other substances, in other words, the length of time the animals live in solutions of these substances, has been used extensively by Child, Hyman and others as a measure of the “‘rate of metabolism.’”’ This practice has been based upon inade- quate knowledge either of the nature of the action of these toxic agents an re OXYGEN GRAM WEIGHT PER UR TIERY: AUG. Fig. 11. Curves show increase in the rate of oxygen consumption by Planaria agilis during regeneration of posterior pieces from experimental fission, and no increase, within the limits of error of the experiment, in the rate of oxygen con- sumption in the anterior pieces. Abscissas represent time in weeks, indicated by dates. Ordinates represent rate of oxygen consumption in ce. oxygen per gram total body weight per 24 hours. The broken line represents the control, the average of three sets of normal worms. The solid line represents the average of three sets of experimental worms before the cutting operation on July 20, and of the posterior pieces after that date. The line of dashes represents the average of the three sets of anterior pieces from the operation. The time of the operation is indicated by the arrow. See table 14. or of the parallelism between the susceptibility of animals and their “rate of metabolism.” The substances first used for this purpose were anesthetics and potassium cyanide, sometimes classed as an anes- thetic. It was supposed that these substances inhibit the oxidations, and they were spoken of as “depressing agents” (1, p. 571); (2, p. 150); (3, pp. 419, 420, 444); (4, p. 65); (8, p. 104). The effect of none of these substances upon the oxidations in Planaria or other animals upon which 464 GEORGE DELWIN ALLEN they were used was determined. The writer (13) has shown that po- tassium cyanide, the agent most used for the susceptibility studies, does inhibit oxygen consumption in Planaria, but it does not follow from this fact that the worms with higher rate of oxidation must be more susceptible to the cyanide, nor that those that are more susceptible to cyanide must have a higher rate of oxidations. Furthermore, many other substances of very different chemical nature and probably of very different physiological action have been used for determining sus- ceptibility. Before drawing conclusions regarding metabolism from the data of susceptibility, in the absence of knowledge of the nature of the action of the toxic agents used, it should be determined, at least, that there is a parallelism between susceptibility and rate of oxidations under all normal conditions. This has not been done excepting for the comparisons with the carbon dioxide production by Planaria in the Tashiro “‘biometer’’ previously mentioned. Upon the basis of the data presented in the present paper, it is possible to make certain compari- sons between susceptibility of Planaria and their rate of oxidations. If the susceptibility is a measure of the oxidations, it must not vary inde- pendently of the rate of oxygen consumption. Table 15 summarizes the facts regarding susceptibility and the rate of oxygen consumption per unit of body weight. Four normal condi- tions are considered; a, increase in the size of the body by growth; }, decrease in the size of the body by agamie reproduction; c, starvation; and d, feeding. Starvation is naturally divided into the early and the later stages, making five items in the table. In the so-called “indirect susceptibility method,” less susceptibility, or, conversely, greater re- sistance, is supposed to indicate a higher ‘‘rate of metabolism,’’ while in the ‘‘direct method” greater susceptibility is supposed to indicate a higher rate of metabolism or rate of oxidations. The letters in the table refer to the following quotations and references to the literature on susceptibility: A. (1) pages 544 to 547. Figures 1 and 2. (4) page 83 and figure 4. B. (1) pages 555 to 564. 3. “In this:connection it should be noted, again, that when well-nourished worms are kept without food, the resistance increases somewhat during the first three or four weeks, as the reserves disappear and after that decreases rapidly”’ (e549). “If the resistance of the worms to anesthetics is in any degree a criterion of age, as it seems to be, then it is evident that while starvation alone does not ) STUDIES ON RESPIRATORY METABOLISM IN PLANARIA TABLE 15 465 Showing that susceptibility of Planaria to the toxic action of alcohol or potassium cyanide varies independently of the rate of oxygen consumption. Changes in sus- ceptibility determined by Child. For references, see text pages 464 to 466 under letters A, B, C, etc., as given in table. determined by the writer (1) CONDITION OF PLANARIA (2) Changes in rate of oxygen consumption (3) (4) SUSCEPTIBILITY TO ALCOHOL AND POTASSIUM CYANIDE Resistance in 2 : “indirect method’ Ll Il Ill IV ee eS ee ER Se oe a eee = Increase in size by growth Decrease in size by regenera- tion of pos- terior piece of large worm Starvation early stages (5-15 days) Starvation later stages (5-8 weeks) Feeding Decreases A (= decreased oxidations ) Increases B (= increased oxidations) Increases C (= increased oxidations) Increases D (= increased oxidations ) then Decreases (= decreased oxidations ) Increases E after 48 hours (= inereased oxidations ) Susceptibility in “direct method” RATE OF OXYGEN CONSUMPTION Decreases F (= decreased oxidations ) Increases G (= increased oxidations ) Increases H (= inereased oxidations ) Increases Tf (= increased oxidations) Decreases J (= decreased oxidations ) Decreases Increases Decreases Constant Increases within 48 hours rejuvenate these animals, except to a slight extent in the early stages,’ yet feeding after a long period of starvation does accomplish this very effectively”’ (1, p. 555). “During the first two or three weeks of starvation before any marked reduc- tion occurs, the rate of metabolism increases but decreases after reduction be- gins (indirect method, meaning that resistance increases during first two or three weeks) (3, p. 437). 3 [talics mine. 466 GEORGE DELWIN ALLEN D. “I have performed numerous experiments with worms in various stages of starvation and always with the same result, viz., the reduced worms show even less resistance than before reduction”’ (1, p. 547). E. (1) page 555, quoted above under C. “The effect of feeding after starvation does not appear as increased resistance to any marked extent until at least 48 hours after feeding. Probably this period of time represents that necessary for the attainment of a certain stage and rate of the metabolic reactions after feeding”’ (1, p. 549). F. (8) pages 423 to 427. (4) pages 93 to 100. G. (4) pages 105 to 110. H. “‘Animals which have been without food for only a few days are distinetly more susceptible to depressing agents than animals which have been fed up to the beginning of the experiment” (3, p. 434). (4) pages 156 to 160, especially table 11, page 157. I. “In all several hundred individuals have been testd and always with the same result, viz., increase in susceptibility from the beginning of starvation on until the animals are reduced to a minute fraction of their original size and death occurs. If the method is valid this increase in susceptibility must mean that the rate of the metabolic processes increases as starvation and reduction proceed, a conclusion exactly the opposite of that reached from my earlier work with the in- | direct method alone”’ (3, p. 427). (4) pages 156 to 160, especially table 11, page 157. “But the results obtained in later investigations by the direct susceptibility method which have been briefly presented above, and the confirmation of these by the estimates of carbon dioxide production, force us to the conclusion that the rate of metabolism increases during starvation. This being the case, the decrease in capacity for acclimation in starved animals cannot be due to a low rate of metabolism, but must be associated with the nutritive condition in some way independent of the metabolic rate”’ (4, p. 165). J. “Each feeding is followed by a distinct decrease in susceptibility, and later, as the animals begin to starve, the susceptibility increases again’’ (4, p. 169). Inspection of this table shows at a glance in what cases susceptibility and rate of oxygen consumption per unit of body weight agree and in what cases they disagree. When the size of the body is increased by growth, part I, the resistance by the indirect method decreases, the sus- ceptibility by the direct method decreases and the rate of oxygen con- sumption decreases. When the size of the body is decreased by experi- mental fission and regeneration, part II, these three items all increase. These facts are consistent with the theory of a relationship between susceptibility and rate of metabolism. But when the conditions of starvation and feeding are considered, the picture changes. During the first stages of starvaton the rate of oxygen consumption falls sharply, column 4, but the susceptibility by the direct method increases instead of decreases. This striking decrease in the oxidations occurs chiefly STUDIES ON RESPIRATORY METABOLISM IN PLANARIA 467 during the first few days. Since the indirect method requires a number of days for making determinations, it is perhaps not well adapted for catching the conditions during this brief period. State- ments were made, however, that the resistance by this method in- creased somewhat during the first three or four weeks without food, as contrasted with the decrease afterwards. During the later stages of starvation, 1.e., after the first 10 days, approximately, the rate of oxygen consumption runs practically constant, while the susceptibility in the direct method continues to increase steadily. In the indirect method, the increase in resistance which begins in the early stages is reported to continue during a total of three or four weeks, after which it is followed by a decrease in resistance. It should be clearly understood that this table and discussion refer only to the first seven to nine weeks of starva- tion, and do not include later stages of more extreme starvation. What changes may occur in the respiratory metabolism, later on, do not con- cern the point under discussion, which is. that the susceptibility of Pla- naria to potassium cyanide and alcohol, and the rate of respiratory metabolism per unit of total body weight vary independently of each other. Such independent variations are clearly shown within the periods which are considered in this discussion. The fall in rate of oxi- dations during the early stages of starvation is large and is not reflected in any decrease in susceptibility. On the other hand, the increase in susceptibility during the period of starvation included in these experiments is large (4, p. 157, table 11) and is not paralleled by an increase in rate of oxygen consumption. It may be noted, furthermore, that the discrep- ancies revealed in the table are too great to be altered materially by minor differences in the respiratory metabolism of different species of Planaria. Feeding causes an enormous increase in the rate of oxygen consump- tion, but it is reported (4, p. 169) that ‘‘each feeding is followed by a distinct decrease in susceptibility, and later, as the animals begin to starve, the susceptibility increases again”’ (direct susceptibility method). In the indirect method, feeding results in an increased resistance as well as in an increased oxygen consumption but it may be noted that “‘the effect of feeding after starvation does not appear as increased resistance to any marked extent until at least 48 hours after feeding.”” The maxi- mum effect of feeding in increasing the rate of oxygen consumption is within this 48-hour period. These comparisons show, therefore, that susceptibility in Planaria varies independently of rate of respiratory metabolism. 468 GEORGE DELWIN ALLEN B. L. Lund (38) and E. J. Lund (11), (39) have shown a similar lack of agreement between susceptibility and rate of oxidations in Parame- cium. Starving Paramecia are more susceptible to potassium cyanide than those that are well fed, but the starving Paramecia consume less oxygen and give off less carbon dioxide. Child (7, p. 217) has criticized Lund because “‘he has apparently failed to recognize an essential point, viz., that susceptibility as measured by progress of death and disinte- gration concerns primarily the ectoplasm or the body-surface and body- wall. Statements to this effect have been made repeatedly in the work on susceptibility.”” These statements, however, give no indication that the “‘rate of metabolism’? under discussion “concerns primarily the ectoplasm or the body-surface and the body-wall.”’ On the contrary, statements have been made repeatedly in the work on susceptibility to the effect that estimations of the carbon dioxide production by Plan- aria in the Tashiro “biometer’’ have confirmed results obtained by the susceptibility method (e.g., (3, pp. 422, 343); (4, pp. 73, 161, 202); (8, p. 104) ).. The following quotation may suffice: The rate of production of carbon dioxide in the starved, reduced animals is practically equal to that in the young, growing animal of the same size, and this rate is much higher per unit of body weight than that in large, old animals. The results obtained by the direct susceptibility method are thus fully confirmed by the estimations of the carbon dioxide production (in the ““biometer’’) (4, p. 161). But they are not confirmed by measurements of the oxygen consump- tion by Planaria made by the writer, nor by measurements of the oxy- gen consumption and carbon dioxide production by Paramecium made by Lund. CONCLUSIONS In conclusion it should be noted that the purpose of these studies is to contribute to the critical analysis of the réle of rate of respiratory metabolism in the animal organism. It may be conceived to be the function of bold and suggestive theories such as those of Child regard- ing the “rate of metabolism”’ to serve as a basis for analysis of all the factors involved in the question. All facts should be welcome and should be examined with critical impartiality to place them in their _proper relation to the general problem. As the analysis proceeds, new aspects appear and new need for discrimination between the various factors involved. The term “rate of metabolism’’ may be used in dif- ferent senses. Attention has been confined in this paper to the rate of respiratory metabolism. Even this term is capable of meaning differ- ent things. What should seem to be the only strictly sound basis for STUDIES ON RESPIRATORY METABOLISM IN PLANARIA 469 comparisons of the relative rates of respiratory metabolism in animals of different size and age are data that give us the rate of respiratory metabolism per unit of weight or volume of living protoplasm in the body of the animal. No other basis is really satisfactory. Material should be selected and methods devised which supply these conditions as nearly as possible. Warm-blooded animals are very unsatisfactory material for such work, and this fact should be considered before draw- ing conclusions of general application from the data of mammalian calorimetry. If the method of susceptibility to the toxic action of such substances as potassium cyanide, when applied to the lower in- vertebrates, could provide a means of approaching the ideal conditions in measuring the ‘‘rate of metabolism” or rate of oxidations, it would be of very great value in the analysis of these problems. This method has been compared in the present paper with measurements of the rate of oxygen consumption in proportion to the weight of the body, and it has been found that the susceptibility does not give a reliable index of the rate of oxidations as thus defined. Since we have no data regarding the rate of oxidations upon the basis of any other definition, we must conclude that, in the present state of our knowledge regarding the action of these substances, only direct methods are reliable for determining the rate of respiratory metabolism. SUMMARY 1. The oxygen consumption by P. maculata and P. agilis decreases progressively during starvation at constant temperature, more rapidly at first and somewhat more slowly later. The body weight also de- ereases during starvation, and the worms become smaller in body dimensions. 2. The rate of oxygen consumption per unit of body weight in starv- ing P. maculata and P. agilis decreases rapidly during the first few days, due to the decreasing accelerative effect of food residuum left from the previous feeding. The length of this period may vary with the tem- perature and the amounts and kinds of food previously ingested, but in the experiments reported it lasted as long as 10 to 14 days, although the accelerative effects were small after the first 7 days. 3. At the end of this period of the accelerative effects of food reserve from previous meals, the rate of oxidations reaches a constant level which is maintained for several weeks in P. agilis (5 to 8 weeks in the experiments reported). During this period of constant rate of oxida- tions, the starvation results in a decrease in the body weight of at least one-half of the original. 470 GEORGE DELWIN ALLEN 4. The ingestion of food by starving P. maculata and P. agilis results in a great increase in the oxygen consumption (80 to 140 per cent in the experiments reported). After this initial rapid rise, which reaches its maximum within the first 48 hours or less, the rate of oxidations per wnit of body weight falls more slowly during 7 to 14 days to reach a constant level. When this constant level is reached after a single feeding, the rate of oxygen consumption per unit of body weight is the same, within the limits of error of the experiment, as it would have been if the animal had not been fed. However, after the rate of oxidations has returned to this constant level the animal weighs more and consumes more oxygen in absolute units than would have been the case if the animal had not been given a meal (see figs. 4 and 6). 5. The later period of starvation, after the accelerative effects of food reserves have disappeared, is the proper basis of reference in studying respiratory metabolism in Planaria. 6. Larger Planaria have a lower rate of oxidations per unit of total body weight than smaller worms of the same species when the latter do not owe their small size to starvation. The experiments reported do not permit making any general statement to cover all cases of differences in size due to starvation alone since the more extreme stages of starva- tion are not included in this study (see paragraph 3 above). 7. After fission of a large worm, the tail piece, which becomes reor- ganized into a small-sized worm, gains a higher rate of oxygen consump- tion per unit of body weight. With regeneration in the anterior piece, which does not involve important alterations in the body, the rate of oxygen consumption remains constant within the limits of accuracy of the method. It is not assumed that the increase in rate of oxidations in the posterior piece is due to the use of measurable amounts of energy in the processes of regeneration or morphogenesis as such. 8. The susceptibility of Planaria to the toxic action of potassium cya- nide and alcohol, as reported by Child, varies independently of the rate of oxidations per unit of body weight, and is, therefore, not a reliable measure of the oxidations as thus.defined. If the rate of oxidations or the ‘“‘rate of metabolism” is defined differently, then it remains to be shown that susceptibility is a reliable measure of either. APPENDIX Since the above was written, three papers have appeared which deal with the respiratory metabolism in Planaria (40), (41) and (42). Hy- man (41) has attempted to strengthen the theory that susceptibility is a STUDIES ON RESPIRATORY METABOLISM IN PLANARIA 471 measure of rate of oxidations by showing that potassium cyanide in- hibits the oxidations in Planaria dorotocephala; her results confirm those of the writer reported in the first paper of this series (13). The two studies supplement each other since the experiments of Hyman covered short periods of time while those of the writer covered longer periods. Hyman argues that ‘‘since cyanides decrease the rate of oxygen con- sumption, it follows that cells or organisms or parts of organisms which have the highest rate of respiratory exchange will be more susceptible to cyanide and will, therefore, die in lethal concentrations of cyanide faster than parts or organisms respiring less actively’ (41, p. 353). The writer does not wish to discuss this argument further than to call attention to the facts observed in Paramecium and Planaria, namely, that fed animals have a higher rate of respiratory exchange but live longer in lethal concentrations of cyanides than starving animals. Child (40) has compared the rates of carbon dioxide production by equal weights of Planaria dorotocephala of different sizes and in differ- ent stages of starvation, as determined by the phenolsulphonephthalein indicator method. The data do not permit a calculation of the actual quantities of carbon dioxide produced, but show that the worms in one tube caused a higher or lower hydrogen ion concentration than those in another tube. Child concludes from his experiments with this indicator method that the rate of carbon dioxide production is greater in small than in large worms, that it “decreases rapidly during the first stages of starvation and continues to decrease more slowly during several weeks, but that in advanced stages of starvation it increases’ (40, p. 256). The advanced stages in which it is reported that the rate of oxidations increases are apparently later than the stages included in the experi- ments of the present writer, although it is hardly possible to compare the rates of starvation in two different species of Planaria under differ- ent conditions of observation. The data regarding differences in rate of oxidations in animals of different size and during the earliest stages of starvation are in agreement with those of the present paper. These conclusions, it may be noted, are very different from either of the two former conclusions of Child which were based on suscepti- bility data. Child himself calls attention to these discrepancies and offers an explanation to preserve the theory that susceptibility is a meas- ure of rate of oxidations. He recalls observations previously neglected, to the effect that during early starvation of Planaria, the susceptibility of the intestinal tract is different from that of the body wall, the former decreasing while the latter increases. The interpretation suggested is that 472 GEORGE DELWIN ALLEN *. the ectoderm and body wall, which maintain their functional activity and subsist in part upon their own substance from the beginning, show a gradual increase in rate of oxidation during starvation, while the rate of oxidation in the alimentary tract undergoes rapid and marked decrease in the absence of food and probably still further decrease more slowly, as the reserves are used. Alimentary tract oxidation in well-fed animals is so large a part of the total oxidation that the de- crease in activity of the alimentary tract in the absence of food brings about a decrease in total CO: production, in spite of the probable increase in CO, produc- tion in ectoderm and body well (40, p. 254). In the absence of any experimental evidence that the oxidations in the body wall change with starvation and feeding, as Child suggests, rather than in accordance with the oxidations of the animal as a whole, the observed facts must be considered damaging to the theory that sus- ceptibility is a measure of rate of oxidations. If the possibility that the oxidations in the body wall may change in a direction exactly oppo- site to the rate of oxidations of the whole animal is pressed, it must be borne in mind that the evidence which is cited in support of the theory, also, consists of measurements of the respiratory exchange of whole ani- mals. Estimations of the total carbon dioxide production by Planaria in the Tashiro “‘biometer’’ have served as proof of the value of the sus- ceptibility method. They were cited for this purpose in the last paper by Child (42, p. 381) although in the preceding paper it was reported that the biometer gave different results (as regards different conditions of nutrition) than the indicator method, so that “‘work with the biometer was discontinued because I came to believe that the method was not suitable for the material’ (40, p. 250). However, whether reliance is placed upon the ‘‘biometer,’’ the indicator method or the writer’s Wink- ler method, the data obtained by these methods have given only the rate of respiratory metabolism of whole animals. The distinction between the rate of oxidations in the animal as a whole and that in particular organs carries the question ultimately to the individual cells. Here we have the information that starving Para- mecia are more susceptible to cyanide but have a lower rate of oxida- tions than fed Paramecia. The explanation suggested by Child is that during starvation in Paramecium, the ectoplasmic oxidations increase while the endoplasmic oxidations, which make up the major part of the whole, decrease. IS Suceepmbilinnt in other animals such as Planaria to be attributed finally to conditions in the surface of the cell rather than to the oxidations of the cell as a whole? What does survival time tell us with certainty about oxidations? d ¢ 4 4 ; ‘ 4 y STUDIES ON RESPIRATORY METABOLISM IN PLANARIA (1) Curip: (2) Curip: (3) Cuiup: (4) CuHILp: (5) CHinp: (6) Cutnp: BIBLIOGRAPHY Arch. f. Entwicklungsmech., 1911, xxxi, 537. Arch. f. Entwicklungsmech., 1913, xxxvii, 108. Arch. f. Entwicklungsmech., 1914, xxxviii, 418. Senescence and rejuvenescence, Chicago, 1915. Individuality in organisms, Chicago, 1915. Biol. Bull., 1918, xxxiv, 49. (7) Cuitp anp Hyman: Biol. Bull., 1919, xxxvi, 183. (8) Hyman: (9) Hyman: Journ. Exper. Zodl., 1916, xx, 99. Journ. Exper. Zo6l., 1917, xxiv, 55. (10) Lusk: Science of nutrition, 3rd ed., 1917. (11) Lunn: This Journal, 1918, xlvii, 167. (12) Kroeu: Respiratory exchange of animals and man, London and-New York, 1915. (13) ALLEN: This Journal, 1919, xlviii, 93. 473 (14) JoHANsson, LANDERGREN, SONDEN AND TicersTapDT: Skand. Arch. f. Phys- iol., 1897, vii, 29. (15) Benepicr: Carnegie Institution Pub. 77, 1907. (16) Leaman, MUELLER, Munk, SENATOR AND Zuntz: Arch. f. path. Anat. u. Physiol., 1893, exxxi, Suppl. 1. (17) Benepict: Carnegie Institution Pub. 203, 1915. (18) Zonrz: Biochem. Zeitschr., 1913, lv, 341. (19) Hii: Journ. Physiol., 1911, xliii, 379. (20) Brunow: Zeitschr. f. Allg. Physiol., 1911, xii, 215. (21) Rusner: Zeitschr. f. Biol., 1883, xix, 535. (22) Benepict: Journ. Biol. Chem., 1915, xx, 263. (23) Benepict, EmmMes, Rors anv Smiru: Journ. Biol. Chem., 1914, xviii, (24) Mreu: Zeitschr. f. Biol., 1879, xv, 425. (25) Du Bots anp Du Bors: Arch. Int. Med., 1915, xv, 868. (26) Du Bots anp Du Bots: Arch. Int. Med., 1916, xvii, 863. (27) GEPHAR T AND Du Bors: Arch. Int. Med., 1916, xvii, 902. (28) Maanus-Levy anp Faux: Arch. f. Physiol., 1899, Suppl. 314. (29) Du Bots: Arch. Int. Med., 1916, xvii, 887. (30) Benepicr AND TaLgBort: Carnegie Institution Pub. 201, 1914. (31) BENEDICT AND Taugor: Carnegie Institution Pub. 233, 1915. (32) Muruin AND Hoosier: Amer. Journ. Diseases of Children, 1915, ix, 81. (33) Bour: Skand. Arch. f. Physiol., 1900, x, 413. (34) Bour anD HasseLBALcH: Skand. Arch. f. Physiol., 1900, x, 149. (35) Montvort: Arch. Ital. de Biol., 1913, lix, 213. (86) Moreuuis: This Journal, 1915, eet 207. (37) Bounurou: Ann. des Sci. Naturelles, 1902, xvi, 1. (38) Lunp: Biol. Bull., 1918, xxxv, 211. (39) Lunn: This Journal, 1918, xlvii, 318. (40) Curb: (41) Hyman: (42) Curb: This Journal, 1919, xlviii, 231. This Journal, 1919, xlviii, 340. This Journal, 1919, xlviii, 372. THE AMERICAN JOURNAL OF PHYSIOLOGY, VOL. 49, NO. 3 139. EXPERIMENTAL STUDIES OF THE URETER Y. SATANI From the Physiological Laboratory of the Johns Hopkins University Received for publication June 23, 1919 A large number of papers have been published dealing with the physiology of the ureter; the main conclusions may be summarized briefly. Engelmann (1) making use of simple inspection described the peri- stalsis and anti-peristalsis proceeding with a certain velocity. On microscopic examination he found no ganglionic structures except in the lower part. He believed, therefore, that the contraction originates and travels in the muscle tissue itself without any relation to extrinsic or intrinsic nerves. Protopopow (2) also making use of ocular ob- servation investigated the movements of the ureter in asphyxia and in different conditions of the circulation of the kidney and _ ureter. His experiments showed that an acceleration of the movements is caused by the distention of the ureter lumen, while a depression results from the ligation of the upper end. Concerning the innervation of the ureter he obtained a motor effect from the splanchnic nerve and a slight inhibitory result by stimulating the anastomosis between the inferior mesenteric ganglion and the plexus hypogastricus. In his work he tested the influence of a number of drugs upon the ureteral movements in situ. Atropin caused first an acceleration, later a depression; diuretin had no effect and caffeine stimulated the con- tractions in small doses, but depressed them in large doses. Besides simple inspection by means of which Engelmann and Pro- topopow carried out their experiments, more recent investigators have studied the movements of the ureter either by recording intra-ureteral pressures or by using excised ureter strips. Papers dealing with the pressure changes in the ureter lumen, by which its movements were studied, have been published by Fagge (3), Henderson (4), Berensnegowsky (5), Lucas (6), Sokoloff and Luchsinger (7). Fagge found a motor effect of the hypogastric nerve upon the ureter; 474 | aT ee Ss EXPERIMENTAL STUDIES OF URETER 475 Henderson and Berensnegowski separately concluded that a ureteral pressure does not depend entirely upon the contraction of the ureter. Lucas mentioned that the contractions are different in size and in number in various parts; the middle part showing relatively large and few contractions, while the upper part gives small and frequent waves of contractions. He also observed a complete prevention of the reflux of the bladder content into the ureter and described an action of the ureter for preventing by its peristalsis the accumulation of urine in the renal pelvis. Sokoloff and Luchsinger obtained contractions by the distention of the ureter lumen. On the other hand some authors as Stern, Lucas (6), Roth (8) and Macht (9) made their experiments with ureter strips removed from the body. Stern records some facts concerning the temperature relations and the proper nutrient solutions for the contractions of the excised ureter. Lucas tested the effects of various drugs; adrenalin, diuretin and barium chloride increased the tone and contraction, while chloroform, ether, chloral and magnesium sulfate exerted a final depressing effect pre- ceded by a slight irritation. Roth stated that oxygenated Locke’s solution of a certain composition is an excellent medium for the de- velopment of the contraction of the excised ureter. He observed two varieties of contractions occurring in a longitudinal strip, namely, large and small contractions. According to his experiments the small con- tractions predominated in the kidney third, while in the lower part large. contractions were most frequently observed. Adrenalin and barium chloride caused an immediate increase in the tone and in the rate of the contraction, while apocodein depressed the activity of the ureter. From the effect of these drugs he assumed the presence of sympathetic nerve endings throughout the ureter. Macht recently published a series of communications under the title of On the pharmacology of the ureter. ‘He used the ureter ring prepa- ration to study the behavior of the circular muscle coat. After sus- pending his preparation in normal Locke’s solution he introduced several drugs such as adrenalin, ergotoxin, physostigmin, atropin, nicotin, morphin and various derivatives of morphin. From these experiments he obtained pharmacological proof that two sets of nerve endings are found in the ureter wall; one belonging to the sympathetics and the other to the parasympathetics. He also demonstrated the presence of ganglia throughout the ureter from the effect of nicotin. 476 Y. SATANI 1. CONTRACTION OF THE EXCISED URETER STRIP a. Single strips A number of observations on the contractions of the excised ureter in nutrient solutions at certain temperatures and effects of certain drugs upon their contractions have been described by such authors as Stern, Lucas, Roth, Macht and others. I have repeated these experiments under the same or different conditions. Method. In this study I have generally used the excised ureter of the pig, because as Macht has stated, the pig’s ureter has the most regular contraction and a longer vitality in artificial nutrient solutions. The material was obtained from a slaughterhouse in the neighborhood of the school. Pigs were bled to death and immediately after killing the ureters on both sides, connected with the kidneys and the bladder, were removed and placed in Locke’s solution at room temperature. For longer preservation of their vitality, they were kept in Locke’s solution on ice. Under these conditions striking contractions may be observed two days or more after removal. A very short strip (2 or 3 mm.) was cut off from the ureter to use as a ring after the manner of Macht, and also a longer section (10 to 20 mm.) as a longitudinal seg- ment (circular fibers were opened). The former preparation registers the contraction of the circular muscle fibers and the latter represents that of the longitudinal fibers. For the nutrient solution, Locke’s solution of the following composition was employed almost exclusively in this work, because Roth found it the most efficient for the development of the spontaneous rhythm and the preservation of the vitality of the excised ureter of the dog. Sodium chloride:..... adie: Gal? MAGES 6 eee eee 9.0 gm. Calerum :chloridé sc. 2.2s8 osc Shoat Bee es Se os eens ene eee Ooo Potassium - chloride, ) 553. osaeeereceee as oe ae eee 0.24 gm. Sodium bicarbonate:’: 5. <.0ce o24 Siena ee Ee 0.3 gm DOXUTOSE.. 5.0 csc eet ce eee Oe eee ee eee 1.0 gm Distilled watertijhies. & ae. MES, ALE. SEs A 00 aa The solution was made fresh for every experiment, and I could re- move the sugar from the solution with very little deleterious effect upon the action of the ureter. Thus a ureter ring (or longitudinal strip) was placed in a bath of 20 ec. of Locke’s solution, which was kept at a constant temperature of 38°C. The solution was also oxy- genated by continual bubbles of oxygen gas. The ureter ring was EXPERIMENTAL STUDIES OF URETER A477 suspended between two hooks, of which the one was fixed at the base of the bath and the other was connected with the arm of a writing lever. Character of the contraction of the ureter To demonstrate the char- acter of the ureteral movements, the ureter rings were employed chiefly because the circular layer is mainly concerned in causing the peristaltic contractions. Every part of the ureter is capable of spon- taneous contraction when placed in oxygenated Locke’s solution at a temperature of 38°C. The beginning of spontaneous contractions of the ureter ring after being placed in Locke’s solution varies in the first place with the part of the ureter from which the ring is taken, and in the second place it depends upon the length of time after its removal from the body. The initial contraction starts immediately in the fresh ureter, while the ureter kept in the refrigerator for twenty-four or more hours begins to contract thirty minutes or even one hour after being placed in the bath. The curve of contraction exhibits a steep ascending part rising almost vertically on a slowly revolving drum. The descending limb falls less steeply so that the contraction curve approaches gradually to the base line. Each contraction is followed by a pause represented as a hori- zontal line for a certain length. Sometimes the contractions follow one another closely, separated by no pause. But as a rule they do not fuse together, the descending limb reaching the level of the base line during the pause. Occasionally the contractions followed so closely, that there was partial fusion into a compound contraction. Finally there was observed a different kind of contraction in which there was a “plateau” at the summit of the curve. Such a curve has the form of an inverted U. In spite of the different types of the contraction curves described above, there is noticed a striking similarity in each tracing made with a single ureter ring, placed in normal Locke’s solution. In other words each ureter ring has only one kind of contraction curve from beginning to end. The height and width of the curves also are the same within certain limits of time except when the contractions become gradually weaker due to fatigue. The rate of the contractions varies in the various segments. Gener- ally they are infrequent at first and then show a gradual increase to a certain rate, which is maintained for many hours even though becoming weaker in amplitude. A478 Y. SATANI The amplitude of the contractions of the several segments also varies. This variation seems to depend to a large extent upon the structure of the muscle layer of the different parts as described elsewhere.! Effects of certain drugs. The above description applies to the con- traction of the ureter ring under normal physiological conditions. An attempt was made to study the action of various drugs upon the contraction of the ureter rings. The definite finding that nerve plexuses and ganglia exist throughout the ureter wall has been described in the anatomical part of my work. Previous investigators are not in accord as to the innervation of the ureter; some maintaining a supply only from the thoracico-lumbar autonomies, the so called ‘‘true sympathetic,” and others finding two sets of nerve fibers, namely the sympathetic and the autonomic nerve supply of sacral root origin, the so-called “ parasympathetic.”’ For the purpose of investigating these nerve supplies, adrenalin and ergotoxin on the one hand and physostigmin and atropin on the other hand were employed, following the general belief that the first two act upon the sympathetic nerve endings while the latter two are excellent agents for revealing the presence of the parasympathetic nerve endings. Experiments with these drugs were carried out according to the fol- lowing schema. . Adrenalin (in small to large doses). . Ergotoxin (in small to large doses). . Adrenalin (in-large doses) and then ergotoxin (in large doses). . Ergotoxin (in large doses) and then adrenalin (in large doses). . Physostigmin (in small to large doses). . Atropin (in small to large doses). . Physostigmin (in large doses) and then atropin (in large doses). . Atropin (in large doses) and then physostigmin (in large doses). . Atropin (in large doses) and then adrenalin (in large doses). 10. Ergotoxin (in large doses) and then physostigmin (in large doses). 11. Nicotin (in small to large doses). Adrenalin even in a small dose stimulates the contraction of the ureter. When a minute quantity of adrenalin (1 drop of 1: 10,000 solution) was added to the bath consisting of 20 cc. Locke’s solution and in which a ureteral ring preparation had been suspended, a marked effect was soon noticed. The spontaneous contractions of the ring showed Cmontoanrwnd 1 To appear shortly in the Journal of Urology. EXPERIMENTAL STUDIES OF URETER 479 a striking increase in rate, although no change in tonus and amplitude was obtained with such a small amount of adrenalin. A ureter which had been kept on ice in Locke’s solution for one day or more and had shown no contractions when suspended at room temperature, began to contract rhythmically. The larger doses (3 to 8 drops of 1: 10,000 solution in 20 ec. Locke’s) caused an immediate increase of the rate, together with a slight increase in the tone. The amplitude of the contractions showed also a very slight increase. Thus adrenalin exerts an influence on the ureter ring in rate, tonus and amplitude in proportion to the increase In concentration. Ergotoxin in relatively small doses (0.5 to 1 mgm. in 20 ec. Locke’s solution) caused an increase in the tone and in the rate of contraction. Fic. 1. Portion of graphic record obtained in experiment of November 6, 1918, with a ureter ring made from the middle of the pig’s ureter in 20 ce. Locke’s solution. 1, spontaneous contractions; 2, the effect of addition of 1 drop of ad- renalin (1: 10,000); 3, the effect of addition of 2 drops of adrenalin (1: 10,000); 4, the effect of addition of 3 drops of adrenalin (1: 10,000); 5, return to Locke’s solution. This effect may be regarded as a primary stage of stimulation. With increasing doses the tonus increased correspondingly, but the rhythmie contractions disappeared after a certain period of time, so that the ureter ring passed into a condition of tonic contracture. I did not find how long and how far this contracture would go on, as I put the ring again in the normal Locke’s solution before observing a relaxa- tion. But there was no relaxation throughout a rather long interval of time while under the influence of ergotoxin. These experiments with adrenalin and ergotoxin indicate the pres- ence of sympathetic nerve endings in the ureter wall. The effects of these drugs are distinctly different in several parts of the ureter, as will be described later. Physostigmin in small and large doses (1.0 to 15 mgm. in 20 ce. Locke’s solution) and pilocarpin in small doses (80 mgm. in 75 ce. 480 Y. SATANI Locke’s) increased the contractions in rate and also in tonus. Atropin in small doses exhibited sometimes a primary stage of stimulation, so that the ureteral contractions increased in rate. But the amplitude of the contractions decreased gradually in every case, and after a longer or shorter interval movements ceased entirely. There was found, however, no sudden disappearance of the contractions of the ureter even after the introduction of a rather large amount of atropin (15 mgm. in 20 cc. Locke’s). Fig. 2. Experiment of November 6, 1918, on a ureteral ring from the middle third of a pig’s ureter. 1, the effect of addition of 0.5 mgm. ergotoxin; 2, the effect of addition of 1.0 mgm. ergotoxin; 3, the effect of addition of 5.0 mgm. ergotoxin; 4, return to Locke’s solution. Fig. 3. Portion of graphic record obtained in experiment of November 8, 1918, with a ring from the lower part of the middle third of the pig’s ureter in 20 ec. Locke’s solution. 1, the effect of addition of 1.0 mgm. physostigmin; 2, the effect of addition of 3.0 mgm. physostigmin. Inasmuch as physostigmin and atropin are regarded as exercising a selective action on the parasympathetic nerve endings, these latter results seem to furnish pharmacological evidence for the presence of sacral autonomic fibers. This conclusion is corroborated by the results obtained from direct stimulation of the nerves, as will be de- scribed below. The effect of combinations of these drugs upon the excised ureter is of interest as throwing more light on the question of its innervatiou. aati EXPERIMENTAL STUDIES OF URETER 481 As I have shown above, ergotoxin antagonized the action of adre- nalin, but had no effect on the stimulating effect of physostigmin. In other words the pressor action of physostigmin was not affected by previous administration of ergotoxin, while adrenalin after ergotoxin was not able to cause contractions of the ureter ring. Moreover in experiments in which atropin and adrenalin were introduced succes- sively after a certain interval of time, it was found that atropin did not interfere with the action of adrenalin although it inhibited entirely the effects of physostigmin. | i AY ] INN th AMyn i tea my a AAA q ay HAN RAY nyt ynAll i) yA fo eet eG ue WA Fig. 4. Portion of graphic representation traced by a ring from the middle of the pig’s ureter in experiment of November 7, 1918. Preparation was placed in 20 ec. Locke’s solution, and shows the final inhibitory action of atropin. 1, the effect of addition of 1.0 mgm. atropin; 2, the effect of addition of 5.0 mgm. atropin; 3, the effect of addition of 7.0 mgm. atropin; 4, the effect of three drops of adrenalin (1: 10,000) after atropin. Fig. 5. Portion of graphic record obtained in experiment of November 6, 1918, with a ring preparation from the middle of the pig’s ureter in 20 ec. Locke’s solution. 1, no effect of addition of 3 drops of adrenalin (1: 10,000) after ergo- toxin; 2, the effect of addition of 5.0 mgm. physostigmin after ergotoxin. These facts may be accepted as showing that these drugs exert their action on different structures in the ureter wall, in accordance with the view outlined above. In addition it was thought desirable to examine the action of nicotin upon the ureter ring, since it is one of the accepted agents used to paralyze peripheral ganglion cells. Its action is to stimulate first and then paralyze. Small doses of nicotin (3 drops of a 1: 100 solution in 20 ec. Locke’s) caused an increase in the contractions, especially in 482 Y. SATANI amplitude, and medium doses (8 drops of a 1: 100 solution in 20 ce. Locke’s) exerted the same effect in a stronger measure, but caused a little decrease in the rate of contractions. Large doses (1 drop of the undiluted solution in 20 cc. Locke’s) paralyzed the contractions immediately. Thus the effect of nicotin upon the excised ureter indicates the exist- ence of ganglion cells in the ureter itself. It also points to the pres- ence of ganglionic structure throughout this organ, since experiments with all parts of the ureter gave positive results of the kind described. Fig. 6. Portion of graphie record obtained in experiment of November 7, 1918, with a ring from the middle part of the pig’s ureter in 20 ec. Locke’s solu- tion, showing the action of nicotin in increasing doses. 1, three drops of nicotin (1: 100); 2, eight drops of nicotin (1: 100); 3, one drop of concentrated nicotin; 4, return to Locke’s solution. b. The use of three strips to compare the contractions of three different parts As pointed out above, the contraction of the ureter ring is markedly different in the several parts of the organ. These differences were observed not only under normal physiological condition, but also after the introduction of drugs in the bathing solution. In the present ex- periments three ureter rings made from the upper, the lower and the | EXPERIMENTAL STUDIES OF URETER 483 middle portions were selected for the purpose of comparing their con- tractions, since in these regions the greatest difference in the structure _ of the muscle coat is found. They were placed in a glass beaker con- taining 75 ec. oxygenated Locke’s solution. Three straw levers. which were of the same length and of the same weight, were connected with the rings. Tracings of these levers were obtained on a revolving drum. In this way curves of the contractions of the three parts un- der similar conditions can be obtained simultaneously. It should be stated that the ureters used in these experiments were not perfectly fresh but had been kept for some hours (3 to 24) in cold Locke’s solution. The three rings did not begin to contract at the same time. The upper ring (the ring made from the upper part of the ureter) began to contract usually immediately after placing it in the bath, and the middle ring followed after a longer or shorter period of time, while the lower ring was quiescent in most of the experiments in the normal Locke’s solution for a number of hours. This finding indicates that the irritability of the ureter varies in dif- ferent parts; the upper end being the most susceptible to stimulation, and the lower parts showing a gradual decrease in irritability. Further there were noticed marked differences in the amplitude of the contractions. The upper ring exhibited small rhythmic con- tractions, while the middle ring gave much larger curves, so that the height of the contractions was many times greater than that of the upper ring. The spontaneous contractions of the lower ring, on the contrary, were very small, much smaller than those of the upper ring. This difference in amplitude of the contractions depends upon the amount and the course of the muscle fibers. In other words, the am- _ plitude of the contraction is proportional to the quantity of the circular muscle fibers. The rate of the contractions also varied definitely in different parts of the ureter. The highest rate was found in the upper ring, while in the middle and the lower ring the rate was slower to about the same degree. The difference in the effects of certain drugs on these three rings is most interesting. Adrenalin caused an increase in the contractions of the upper and middle rings in both rate and amplitude; its effect being stronger on the upper ring. On the lower ring, on the:contrary, adre- nalin had only a very small effect, causing a minute increase in the rate or sometimes no reaction at all, even in large doses. The re- oul] aseq qoddn oy} wo. to}0IN 831d B Jo ‘plooat Yyanoy {Buta TOMO] B JO SJUOUIOAOUL ‘pAodad paTyy ‘SULI o]pprut B Jo 980} “pl0de1 puodos ‘41"d SUIL BJO suOT{ORIVUOD ‘piooer soddy “UOTNIOS $,9YOT poo v ut SINOoYy 10¥ ydoy useq pry yorym $ SSULI 9014} JO SUOT}OBIZUOD SnosuRyuodg “SIGI “ZZ JequIvAON Jo quoult1odxe ut Poure7qo p1odsot orydury +) ‘Sly SATANI whe 484 EXPERIMENTAL STUDIES OF URETER A485 sponse of the middle and lower rings to adrenalin started immediately after introducing the drug, while the upper ring began to react after a certain period of time. I cannot find a probable explanation for this result. Physostigmin exerted its effect on the middle and lower ring, produc- ing an increase in the rate and amplitude. Vigorous contractions were evoked in a quiescent lower ring, which had remained motionless for many hours after being placed in Locke’s solution. In the upper ring, however, physostigmin had either a slight effect or no pressor action at all. In regard to the beginning of the contraction there was found a Fig. 8. Portion of graphic tracing obtained in experiment of November 21, 1918. Three rings were suspended in 75 cc. Locke’s solution, to which adrenalin was added (8 drops of 1: 10,000 solution). Upper record, the contractions of the upper ring; second record those of a ring from the middle part; third record, movements of the lower ring; forth record, base line. 1, addition of adrenalin. reversed order compared with that of adrenalin. Contraction de- veloped immediately, if at all, in the upper ring while in the middle and lower rings contractions appeared only after a certain interval. Comparing the findings of the experiments carried out with three rings, it is seen that adrenalin has a stronger influence at the upper part of the ureter, while physostigmin exerts a more marked effect on the lower part. The middle part reacts to these two drugs almost in the same degree. These facts indicate that the upper part has a nerve supply from the sympathetics chiefly, while the larger part of the nervous element in 486 Y. SATANI the lower part belongs to the parasympathetic system. In the middle part there exist both sets of nerve fibers, seemingly in the same quantity. Comparison of the effects of adrenalin and physostigmin on the tonus of the three rings develops an interesting difference. Adrenalin caused an increase of the tonus in the upper and middle rings only to a slight degree. On the contrary, physostigmin produced tonic contractions in the middle and lower rings much more striking than the tonus of the upper and middle rings produced by adrenalin. This and other facts seem to indicate a difference between these two sets of nerves in the ureter in respect to their physiological functions; the action of the Fig. 9. Portion of graphic tracing obtained in experiment of November 21, 1918. Three rings of a pig’s ureter were placed in 75 cc. Locke’s solution, to which 15 mgm. physostigmin was introduced, 1. Upper record, the contrac- tions of the upper ring; middle record, those of the middle ring; lower record, movement of the lower ring. sympathetics has an evident relation to the rhythmic contractions of the ureter, while the parasympathetics may act rather as a pressor nerve for heightening the tonus. 2. EXPERIMENTS UPON STIMULATION OF THE EXTRINSIC NERVES After administration of 1 grain of morphin a dog of medium size was fixed on the holder. The animal having been anesthetized by ether and tracheotomized, the abdominal cavity was opened along the linea alba from the xyphoid process to the symphysis pubis. For the pur- EXPERIMENTAL STUDIES OF URETER 487 pose of making a sufficient space to find the left splanchnic nerve in the region above the suprarenal gland, another incision was made on the left abdominal wall along the lower border of the last rib. The intes- tines were drawn to the right side and the viscera, as well as the rest of the abdominal wall, were covered with warm towels. In this way the left ureter could be seen completely from the kidney to the bladder. For a little while after opening the abdominal cavity the regular peri- staltic movements were noticed at the rate of 3 to 5 per minute. They disappeared, as a rule, in a few minutes but in some cases might con- tinue for hours. In some dogs the ureters remained motionless even immediately after opening the abdomen. The method employed in obtaining graphic records of the ureteral movements consisted in connecting the lumen of the ureter with a water manometer, the undulations of the column of water being then transmitted by means of a piston recorder to a revolving drum. The connection with the ureter was made by the following method. After opening the bladder cavity by a long sagittal incision, a small cannula with a thin tip was introduced into the orifice of the left ureter. To avoid losing the cannula from the orifice and to keep the connection water-tight, four weak rubber bands were used, one end being hooked to the mucosa of the bladder in the neighborhood of the orifice and the other end being tied to the glass cannula, some distance from the orifice. By this method the ureter was retained in its normal connection with the bladder, and no injury was inflicted upon the nerve and blood supplies which ascend up the ureter from the bladder. To prevent an increase of the intra-ureteral pressure due to the urine secretion of the kidney, the upper end of the ureter,was squeezed with a weak artery- clamp. When all preliminary arrangements had been made the intra- ureteral pressure was raised by injecting Locke’s solution through the cannula into the ureter lumen, which was thereby distended to a certain degree. PROTOCOLS OF TYPICAL EXPERIMENTS All of the experiments of the present series were made on dogs. The results of three typical experiments are reported. Experiment 3. December 11, 1918. The preliminary operation described above was made. After tying the trunk of the left splanchnic nerve in the re- gion above the suprarenal gland, the nerve was cut and the distal stump of the nerve was stimulated with induction currents for half a minute. As a result 488 Y. SATANI of this stimulation there occurred after a quarter of a minute three contrac- tions in the previous quiescent ureter. The stimulation was repeated with the result of one contraction for each stimulation. But the interval between the stimulation and the appearance of the contraction became gradually longer, as the stimulations were repeated. After the seventh stimulation there was no response owing probably to a fatigue of the nervous mechanism. By pulling the splanchnic nerve also there occurred a series of contractions (mechanical stimulation). Fig. 10. Portion of graphic record obtained in experiment of December 11, 1918. Upper record, contractions of the ureter’from stimulating the splanchnic nerve; lower record, time record in minutes. 1, 2, 3, 4,5, 6,7, stimulations of the nerve. The left pelvic nerve was dissected out in the pelvic cavity and was then ligated and cut. On the distal side of the nerve many branches making up a plexus spread in the form of a fan over the side of the bladder. The uppermost one of these branches, which seemed to be larger than the other fibers, was stimulated electrically. There was observed, however, no contraction of the ureter. But when the electrodes were brought under the nerve plexus and touched a certain branch, there appeared suddenly contractions, which con- tinued rhythmically for a short time, giving a series of contraction curves. An interesting event, which indicated clearly that mechanical stimulation is able to cause contractions of the ureter, happened during this experiment. Fig. 11. Portion of graphic record obtained in experiment of December 11, 1918. Upper tracing, contraction of the ureter from mechanical stimulation (squeezing) of the pelvic nerve, 1. Lower record, time record. EXPERIMENTAL STUDIES OF URETER 489 I lost the distal stump of the pelvic nerve, as its end escaped from the liga- ture. When I found it after a little while and squeezed it with an artery for- ceps, there occurred a series of contractions. The contractions followed so closely, especially in the middle section of the series, that they fused into an incomplete compound contraction, showing an increase of the tonus of the ureter. Experiment 6. December 18, 1918. The operation and the arrangement of the apparatus were the same as in the preceding experiment. At first the ureter remained quiescent. But electrical and mechanical stimulatlon of the splanch- nic nerve caused a contraction or a series of contractions immediately. After a few stimulations of the splanchnic nerve the ureter showed somewhat irregular spontaneous contractions, which continued for hours.: Stimulation of the splanchnic nerve had an effect of making the rhythm more regular. Stimulation of the pelvic nerve gave also contractions of the ureter. The curves of contraction, however, were lower and wider than in the case of the contractions due to stimulation of the splanchnics. = ?—_ ae et Fig. 12. Portion of graphic record obtained in experiment of December 18, 1918. Upper tracing, contractions of the ureter from stimulating the splanchnic nerve mechanically, 1, and by induction current, 2. Lower record, time record. In regard to the number of contractions following a single stimulation of either the splanchnic or pelvic nerves the result varied within wide limits, sometimes only a single contraction appearing either immediately or after a short time, or sometimes a number of contractions succeeding each other. Comparing the contractions caused by stimulating the splanchnic and pelvic nerves, a difference was observed. The contractions caused by the stimulation of the splanchnic nerve were quicker and stronger, while the contractions caused by stimulating the pelvic nerve were slower and weaker. This difference seems to indicate that the two sets of nerves may have different actions upon the ureteral movements. Further there was noticed a number of vigorous contractions by stimulating a nerve trunk, which was found under the left kidney. It was situated 2 or 3 em. below the origin of the renal artery, over the ventral side of the aorta. The contractions continued for several minutes at the rate of 4 to 8 per minute. But the nerve was not dissected out to find its origin. Experiment 11, January 8, 1919. The ureteral movements caused by stimu- lating the splanchnie and pelvic nerves were just the same as in the previous experiments. In this experiment a very delicate branch from the inferior mes- THE AMERICAN JOURNAL OF PHYSIOLOGY, VOL. 49, NO. 3 490 Y: SATANI enteric nerve was dissected out. It had its origin from a point of the inferior mesenteric nerve in the neighborhood of the inferior mesenteric ganglion, and divided soon after leaving the inferior mesenteric nerve into two or more branches, the upper one ascending somewhat and the lower branch taking a more descending direction. These final branches evidently had their terminations in the ureter wall. Stimulation of this branch of the inferior mesenteric nerve with induction currents caused an immediate and marked diminution in the rate of a series of spontaneous contractions which the ureter had been giving. After cessation of the stimulus the rate of contractions increased markedly, so that. it became one and a half times more than that during the spontaneous contractions. In regard to the amplitude of the contractions, however, there was observed almost no change during and after stimulation of this nerve branch. From this finding the small branch from the inferior mesenteric nerve may be regarded as an inhibitory nerve to the movements of the ureter. Protopopow states Fig. 13. Portion of graphic tracing obtained in experiment of January §8, 1919. Upper record, inhibition of the contractions of the ureter from stimulating the ureteral branches of the inferior mesenteric ganglion. 1, point of beginning of stimulation; 2, end of stimulation. Lower record, time record in minutes. that stimulation of the anastomosis between the inferior mesenteric ganglion and the hypogastric plexus caused usually no acceleration, but sometimes rather a slowing of the ureteral contractions. When the hypogastric nerve was stimu- lated electrically, there was a very weak inhibitory result. This nerve was cut at the middle and the distal stump was stimulated, causing no change in the movements of the ureter. On the other hand, stimulation of the proximal stump caused clearly an inhibitory effect of the ureteral move- ments though in a slight degree. These Yacts accord with Protopopow’s find- ings and seem to indicate that the electrical stimulation reached the inferior mesenteric ganglion through the hypogastric nerve and presumably as an axon reflex influenced the ureteral contractions through the nerve branches passing from the inferior mesenteric nerve to the ureter. Sometimes there occurred evidence of tonic contractions after stimulation of the branch was stopped. Painting and intra-ureteral injection of adrenalin, atropin and other drugs caused their respective effects in the same manner on the ureter in situ as in ring preparations, but to a slighter degree. mA EXPERIMENTAL STUDIES OF URETER 491 As a result-of these three typical experiments and others which gave similar results light is thrown upon the important question of the in- nervation of the ureter. The motor effect of stimulation of the splanch- nie nerve indicates evidently that there are nerve endings of the tho- racico-lumbar (sympathetic) outflow in the ureter. As this fact has been stated by many different observers we may assume that it can be accepted without question. In almost all of my experiments (nos. 3, 4, 6, 7, 8, 9, 10, 11, 12, 14, 15) this result was obtained. . In regard to the innervation of the ureter by the pelvic nerve, in other words the presence of parasympathetic nerve endings, there has been some difference of opinion. In most of the present experiments (nos. 3, 4, 6, 8, 9, 11, 12, 14) definite evidence was obtained of the existence of the parasympathetic motor neurones, which come up to the ureter through the connector nerve fibers of the sacral outflow, i.e., the pelvic nerve. Some objections may be made against the ex- periments on the ground that the electrodes must be brought so near to the ureter that the currents might escape into the ureter through the tissues which accompany the fibers of the pelvic nerve. But the fact that mechanical stimulation such as squeezing the nerve, as in experiment 3, also caused a series of vigorous contractions, can be regarded as indisputable evidence that the pelvic nerve carries motor fibers to the ureter. This result accords also with the results which were obtained pharmacologically with the ring preparations of the excised ureter, as described above. The method of experimentation described in this section did not throw any light upon the relative distribution of the sympathetic and parasympathetic fibers. The conclusion in regard to this point rests upon the pharmacological results already described. DISCUSSION On the peristalsis of the ureter. All smooth muscle tissues possess the power to contract, but they need to be in close continuity with nerve elements for the development of the contraction. The ureter has a well developed muscle coat, and within the ureter wall there is found a complete nervous system composed of a network of fibers with many ganglion cells as shown by many authors and confirmed in my study of the histology of this organ. According to my finding there are two nerve plexuses situated in the outer fibrous coat and submucosa immediately embracing the muscle layer over its outer 492 Y. SATANI and inner sides. From the close situation of these nerve plexuses to the muscle layer we may infer that the contractions of the ureter are due to this intrinsic nervous system. That the ureter is capable of con- tracting spontaneously without the action of extrinsic nerves, is dem- onstrated by the spontaneous contractions of excised pieces when kept in Locke’s solution at a temperature of 38°C. In regard to the direction of the contraction wave of the ureter, which begins at the upper end and proceeds toward the bladder in the form of a peristalsis, the author finds an immediate explanation in the experiment in which three ring preparations made from different parts of the ureter were observed to contract after different periods of time; the upper end being most responsive to a stimulus and the responsive- ness decreasing gradually toward the lower end. In the normal con- dition in situ the contraction wave develops at the upper end on ac- count of the greater irritability at that end, favored perhaps also by the mechanical pressure of the secretion. On the innervation of the ureter. The innervation of the ureter has been investigated by many authors, whose statements are quite di- vergent. Langley and Anderson (10) dissected out three ureteral branches from the hypogastric nerve in the cat. Protopopow sug- gested that the splanchnic nerve augmented the peristalsis of the ureter in the dog. Fagge and Stern observed an accelerating effect of the hypogastric nerve. Elliot (11) also described a slight movement of the ureter by stimulating the hypogastric nerve. Gaskell (12) in his monograph on The involuntary nervous system mentions that the segmental ducts, namely the uterus, the ureter and the vas deferens, possess both motor and inhibitory fibers, which arise from nerve cells belonging to the thoracico-lumbar outflow, but adds that there is no evidence that these structures are connected in the slightest degree with the pelvic nerve. He states also that the nerve cells with which the sympathetic nerve fibers are connected are placed in the ureter itself. Gaskell’s argument for the innervation of the ureter by the sympatheties only rests largely upon embryological considerations. i In my experiments I found pharmacologically, on the one hand, the presence of both the sympathetic and parasympathetic nerve endings. On the other hand, I confirmed by stimulation the innervation of this organ by both the splanchnic andthe pelvic nerves. There is, therefore, no doubt of the existence of sympathetic and parasympathetic nerve endings in the ureter wall, connected with the preganglionic fibers of te + GEN peas 2 SES AS a a ee a 6 ets i + EXPERIMENTAL STUDIES OF URETER 493 the thoracico-lumbar and sacral outflow (i.e., the splanchnic and pelvic nerves) respectively. In two cases small nerve filaments were followed anatomically from the pelvie nerve to the ureter. Delicate filaments given off from the inferior mesenteric nerve and going to the ureter were found on stimulation to exert an inhibitory effect. On the prevention of the reflux of the bladder content into the ureter lumen. It is an important problem as to whether or not the bladder content can flow back into the ureter under normal conditions. Asa matter of fact various clinicians describe an ascending nephritis, which follows infection of the bladder. If such is the case there is some doubt as to whether the deleterious condition in the bladder may have an effect on the kidney by direct transmission through the ureter, or in some indirect way. Some urologists as Petit, Hallé, Sappy, Zuckerkandle and Tuchman, and the physiologist, Sigmund Mayer, have stated that the normal closure of the ureter is competent to prevent a reflux. Harrison, from his clinical observation, believed that regurgitation can only be brought about by very gradual means, not by a sudden flow into the ureter. Guyon and Albarran obtained the same result as Harrison in their ex- perimental work. On the other hand, most of the experiments of Lewin and Goldschmidt (13) have indicated the possibility of a reflux even in normal conditions, but Lucas claims that the normal uretero- vesicular valves can wholly prevent the reflux of the urine. As a result of my experiments I find that normally there is no reflux into the ureter, although from my anatomical findings and those of many authors there is found no special structure of the nature of a sphincter at the end of the ureter. In some of my experiments on dogs and pigs the bladders were re- moved with a small adjacent part of the ureters and urethras. The bladder was gradually distended by salt solution to the greatest de- gree, but there was no drop of leakage from the ureter stump; and the bladder thus distended could be kept for days. This fact indicates that the bladder content may not flow back into the ureter lumen even with fullest distention of the bladder. After destroying all mus- cles of the bladder wall, which cover the intraparietal part of the ureter, a slow leakage was produced through the ureter. The preven- tion of a reflux is referable to a physical mechanism to a large extent. The distended bladder muscles over the ureter press the ureter to- gether closely and moreover the slit-like opening of the ureter tends to 494 Y. SATANI close the opening so that even after destruction of the bladder muscu-: lature the leakage back into the ureter is very slow. In addition to these physical mechanisms the prevention of a renin is probably aided by a more distinctly physiological activity. A layer of longitudinal muscle is found on the outer side of its intraparietal part, while the Waldeyer’s ureter sheath covers the medial side of the small section just above the intraparietal part. The contraction of the former tends to close the orifice, and the contraction of the latter causes the lip-shaped upper rim to protrude. These mechanisms thus assist in preventing the reflux of urine into the ureter. CONCLUSIONS 1. The excised ureter gives spontaneous contractions in oxygenated Locke’s solution. The contractions vary in rate and character with different individuals. 2. The amplitude and rate of the spontaneous contractions vary also in different parts of the ureter. The contractions of the middle part are large and slow, those of the kidney end are lower and faster, while at the bladder end the contractions are very small in size and slow in rate. These differences so far as size is concerned are correlated with the different thickness of the circular muscular coat which has its largest development in the middle section. 3. Adrenalin and physostigmin stimulate the movements of the ureter. . Adrenalin affects the upper portion of the ureter more strongly while physostigmin gives a more distinct reaction on the lower portion. 4, Ergotoxin in large doses antagonizes the action of adrenalin but has no influence upon the action of physostigmin. With atropin in large doses the opposite reaction holds; it antagonizes the action of physos- tigmin but not of adrenalin. In accordance with the usual interpre- tation, these reactions indicate the presence in the ureter of sympathetic and parasympathetic fibers. 5. Nicotin in large doses paralyzes the movements of all parts of the ureter, thus corroborating the histological finding of ganglion cells along the whole length of the ureter. ; 6. The irritability of the ureter as displayed by the rhythmic con- tractions of isolated rings in Locke’s solution is greatest at the upper end and diminishes gradually toward the bladder. 7. The action of adrenalin and ergotoxin is most marked at the upper end of the ureter, while the characteristic effects of physostigmin EXPERIMENTAL STUDIES OF URETER 495 and atropin are displayed especially by rings taken from the lower end. The middle section reacts somewhat equally to the two sets of drugs. It is inferred from these facts that the upper end is inner- vated chiefly by sympathetic fibers, and the lower end by parasympa- thetic fibers, while in the middle there is an approximately equal dis- tribution of the two sets of fibers. 8. Stimulation of the peripheral end of the splanchnic nerve causes the development of contractions in a quiescent ureter. Stimulation of the peripheral stump of the pelvic nerve also causes the development of contractions in the ureter. 9. The ureteral muscles receive inhibitory fibers by way of the communicating branch to the inferior mesenteric ganglion. The action of these fibers is to slow the rhythm of the ureteral contractions. 10. The prevention of a reflux of the bladder content into the ureter is complete under normal conditions. The closure is effected mainly by a physical mechanism, but is assisted by the physiological activity of the musculature at the intraparietal portion of the ureter. BIBLIOGRAPHY (1) ENcreLMaANN: Arch. f. d. gesammt. Physiol., 1869, 11, 248. (2) Prorororow: Arch. f. d. gesammt. Physiol., 1897, Ixvi, 1. (8) Faage: Journ. Physiol., 1902° xxvill, 306. (4) Henprrson: Journ. Physiol., 1905, xxxiii, 175. (5) BrRENSNEGOWSKyY: Centralbl. f. Physiol., 1908, xxii, 461. (6) Lucas: This Journal, 1906, xvii, 392; N. Y. Med. Journ., 1907, xxxvi, 254; This Journal, 1908, xxii, 245. (7) SokoLorr uND LucusinGeER: Arch. f. d. gesammt. Physiol., 1881, xxvi, 464. (8) Rotru: This Journal, 1917, xliv, 275. (9) Macur: Journ. Pharm. Exper. Therap., 1916, viii, 155, 261; 1916, ix, 197, 287, 427; 1918, xii, 255; Journ. Urology, 1917, i, 97. (10) LANGLEY AND ANDERSON: Journ. Physiol., 1895, xix, 73. Laneury: Schaefer’s Textbook of physiology. (11) Exuiorr: Journ. Physiol., 1906, xxxv, 73. (12) GasKEeLL: Monograph on the involuntary nervous system, 1916. (13) Lewin unpD Goupscumipt: Arch. f. path. Anat. u. Physiol., 1893, exxxiv, 33. THE AMERICAN JOURNAL OF PHYSIOLOGY VOL. 49 SEPTEMBER 1, 1919 Noi 4 A QUANTITATIVE STUDY OF THE EFFECTS PRODUCED BY SALTS OF SODIUM, POTASSIUM, RUBIDIUM AND CALCIUM ON MOTOR NERVE OF FROG ESTHER GREISHEIMER From the Hull Laboratories of Physiological Chemistry and Pharmacology, University of Chicago Received for publication June 8, 1919 INTRODUCTION Mathews (1) in the course of his investigations on the nature of chemical and electrical stimulation found the chloride of rubidium to be the most powerful stimulating agent for motor nerve of frog. Owing to conflicting reports in the literature on the subject, further investi- gation seemed desirable. A brief review of the physiological effects of the rubidium salts and the related sodium and potassium salts will be given. Bunsen discovered rubidium in 1861 and knew from the chemical behavior of its compounds that it belonged in the group of alkali metals. In most of its peculiarities rubidium exhibits the greatest similarity to potassium, which it follows in the periodic system. Grandeau (2), however, as early as 1864 concluded that rubidium was more nearly related to sodium than to potassium. He injected 1 gram of the salt dissolved in 15 ce. of water into dogs. If the dog died the salt was considered toxic, but if the animal recovered sufficiently to run about the salt was considered ineffective. Grandeau, by these methods, found potassium alone to be toxic, and sodium and rubidium chlorides to be ineffective, in equal dosage. Ringer (3) made a comparative study of these chlorides, using the ventricle of the frog’s heart, in which he maintained an artificial cir- 497 THE AMERICAN JOURNAL OF PHYSIOLOGY, VOL. 49, NO. 4 498 ESTHER GREISHEIMER culation. On using 1 ec. of a one and two hundred five thousandths (1.205) per cent solution of rubidium chloride in 100 cc. of normal saline solution, he observed the ventricular contractility to grow less and less until it had disappeared. On addition of small amounts of either strontium or calcium chloride (8.5 to 5 ee. of 1 per cent sol. to 100 cc. of the circulating fluid) fair contractions speedily returned. A calcium salt in saline broadened the beat, rounded its top and greatly retarded dilatation. Rubidium, like potassium, obviated these effects, and restored to the beat its normal character. Blake (4) criticised the work of Ringer because it had been done on the isolated organs of adead animal. He believed that the physiological action of a salt should be determined by introducing it directly into the veins or arteries of a living animal, so that it could, with the least dis- turbance possible, be brought into direct contact with tissues whose re- actions he wished to investigate. He injected the chlorides of rubidi- um, potassium and sodium into the veins or arteries of frogs in order to test the effects on the heart. His results differed from those of Ringer in that he found sodium and rubidium to behave similarly and potassium to be exceptional in its behavior, but he failed to give the data obtained. Harnack and Dietrick (5) injected rubidium chloride subcutaneously into frogs, and compared the results with those following the injection of potassium chloride. These salts did not essentially affect the heart muscle when given in doses of about thirty milligrams. From the results obtained they concluded that the differences between potassium and rubidium salts were quantitative, potassium being the stronger of the two. A few investigations were carried out in which isolated muscle was placed in rubidium or potassium chloride, and a rapid decrease in height of contraction following stimulation followed in either salt. These investigators gave no data from experiments on motor nerve of frog, but simply stated that rubidium salts appeared to affect motor nerve to a slight degree only. Brunton and Cash (6) observed that ‘‘motor nerve was not paralyzed by rubidium except in very large doses.” The height of contraction of muscle was increased by rubidium and potassium alike. The lethal activity on frogs of the chlorides used placed the metals in the following Series, potassium being the strongest: potassium > rubidium > barium > caesium > lithium > strontium > sodium > calcium. Richet (7) studied the effects of both subcutaneous and intravenous injections of rubidium and potassium chlorides on fish, frogs, guinea 4 | QUANTITATIVE STUDY OF EFFECT OF SALTS ON NERVE 499 pigs, pigeons and rabbits. The results were similar on the various animals, rubidium chloride being slightly less toxic than potassium chloride. Botkin (8) injected these chlorides into dogs and found that rubidium chloride exerted effects similar to smaller doses of potassium chloride. Griitzner (9) has, as had Ranke (10) and Biedermann (11) before him, found the chloride of potassium, even in dilute solution, intensely toxic. In stimulating action, caesium was found most active, rubidium next, and potassium had no noticeable stimulating action at all. But in toxicity potassium stood highest, rubidium next and caesium lowest. Calcium also was found to be toxic to the nerve. Many investigations on the antagonisms of these salts have been carried out. Loeb (12) found pure sodium chloride a strong poison for many (if not all) marine animals. He considered the poisonous effects due to the sodium ion. Equimolecular solutions of calcium and potassium chlorides were also found poisonous, but a combination of the three ions was not poisonous. Loeb and Cattell (13) showed that eggs of Fundulus poisoned with potassium chloride were unable to recover when placed in distilled water or in a saccharose solution, while they recovered when placed in an x salt solution, or in acidi- fied water. The relative efficiency of the salts for inducing the re- covery of the heart beat increases, first with the concentration of the salt in the solution, then with the valency of the anion of the salt, the valency effect apparently following Hardy’srule. Loeb and Ewald (14) studied the inhibitory effect of calcium on motor nerve of frog. A portion of nerve immersed in an M sodium chloride solution results in twitching of the attached muscle. They found that 2 ce. of an x calcium chloride solution per 100 cc. of a “ sodium chloride are re- quired to suppress these twitchings. On adding a quantity of calcium not quite high enough to inhibit entirely the effect of the stimulating salt, the latent period of stimulation was considerably increased. This fact harmonized with Loeb’s assumption that the inhibitory effect of calcium is due to a prevention or a retardation of the diffusion of the stimulating salt into the nerve. Burridge (15) perfused isotonic sodium chloride through the frog’s heart. Stoppage in the dilated condition and loss of electrical irrita- bility followed. Calcium opposed these effects. Zoethout (16) found that gastroenemii of frogs were thrown into contraction on immersion in ¥ potassium chloride. He showed that 500 ESTHER GREISHEIMER treatment with sodium chloride previously, or the simultaneous in- troduction of sodium and potassium chlorides, hindered the develop- ment of the potassium contraction. A similar treatment with calcium chloride reduces the extent of the potassium contraction, and lengthens the latent period. He used 1 to 10 ce. u CaCl, and 10 ce. of 6 per cent cane sugar solution followed by 1 ce. 4 KCl in 10 ce. 6 per cent cane sugar. Lillie (17) found that Arenicola larvae lost muscular contractility gradually in pure isotonic solutions of non-electrolytes, such as cane sugar and dextrose. Pure solutions of sodium salts induced well- marked contractions in such larvae, and the addition of calcium chloride (as low as ssn) to sodium chloride solutions, increased the ability of the latter to restore normal contractility. Potassium and rubidium exerted a more vigorous effect than sodium. Joseph and Meltzer (18) used the gastrocnemius and the sciatic. The muscle in sodium chloride alone stopped contracting after an hour and a half or two hours, while if the solution contained also some calcium, the contractions continued from six to eight hours. In nine out of ten experiments the nerve in calcium chloride lost its conductiv- ity in two or three hours, but sodium chloride caused no loss of con- ductivity in the sciatic even after many hours. Groves (19) stated that the various salts of potassium killed the nerve so rapidly that the results were not clear and uniform. Oster- hout (20) used young plants of a fresh water alga, Vaucheria sessilis, which can live three to four weeks in distilled water. These plants were killed in a few minutes by — sodium chloride, and in a few days by a sodium chloride. The toxicty of a a solution of sodium chloride was inhibited by the addition of calcium chloride in the proportion of one part of calcium to one hundred parts of sodium. Potassium chloride was also able to neutralize the poisonous effect of the pure sodium chloride. Burnett (21) continued the work of producing glycosuria in rabbits by the injection of sodium chloride. The usual glycosuria was 0.25 per cent in rabbits with injection of pure sodium chloride, but this was reduced, varying from a trace to 0.03 per cent on injecting x sodium chloride to which had been added some potassium. Burnett added 2.2 molecules of potassium chloride per 100 molecules of sodium chloride. Calcium chloride was found equally effective in preventing glycosuria. QUANTITATIVE STUDY OF EFFECT OF SALTS ON NERVE 501 Miyake (22) found 25 ce. of y sodium chloride plus 5 ce. AI calcium chloride the most favorable mixture for the growth of rice seedlings. A similar mixture, using potassium chloride in place of calcium chloride was found favorable. Cramer (23) studied the effects of sodium and calcium salts on the growth of cells of a transplantable mouse carcinoma. The cells were immersed for an hour or two in isosmotic solutions of sodium and calcium chlorides. The subsequent transplantation showed a very distinct inhibition of growth on the part of the cells which had been suspended in calcium chloride. The growth of the cells which had been suspended in sodium chloride showed slight, if any, inhibition. The inhibition of growth produced by the calcium ions can be neutralized by a subsequent suspension of the cells in sodium chloride solution. Mathews’ (1) observations on nerve were more thorough than any of the preceding. He found that all the sodium salts stimulated the motor nerve, and likewise potassium chloride in one-fourth molecular solution or stronger, while solutions weaker than this never stimulated, but very rapidly depressed the nerve. Rubidium chloride was found to be the most powerful stimulant of the chlorides, and the irritability of nerves in this solution was lost very rapidly. In this observation Mathews (1) differed from Griitzner (9) who found caesium a more powerful stimulant than rubidium, and from Zoethout (24) who found that nerves were not stimulated on beingimmersed in rubidium chloride. Zwaardemaker and Feenstra (25) have made the most recent ob- servations on these related salts. They have found that the potassium in Ringer’s solution may be replaced by rubidium, uranium and thorium, and that the necessary quantities are proportional to their radio- activities. Their investigations were made on heart of frog. Prof. A. P. Mathews suggested that further investigations be carried out on these salts, so the writer undertook a quantitative study of the toxic effects produced in each salt alone, and then in various com- binations. These observations have necessarily been limited owing to the great difficulties in procuring rubidium salts. The purpose of this paper is not to set forth an exhaustive discussion on the nature of the nerve impulse, nor on the manner in which salts act, but simply to state the results observed on studying these salts in a thoroughly - quantitative manner. The statements that “‘calcium rapidly depresses the nerve” and that ‘‘potassium is very toxic’? must be reduced to quantitative terms. It is hoped that these results may be a helpful stepping stone to the next investigator in this line of work. 502 ESTHER GREISHEIMER METHODS The sciatic nerve and the gastrocnemius muscle of the leopard frog were used. The sciatic was not cut, the whole sacral plexus with an attached bit of spinal column being left intact. It was believed that more constant results could be obtained if nerves were kept as nearly uninjured as possible. The frogs were brought from the tank and the preparation rapidly made, scarcely five minutes elapsing between the pithing of the frog and the mounting of the preparations in the moist chambers. The fact that frogs are in varying conditions of health is a great uncontrollable source of error. Sex appears to make no difference in the results, but the writer believes that humidity will in the future be shown to be an influential factor in nerve work. A 4 em. length of nerve nearest the muscle was immersed in a paraffin cup containing 5 cc. of the solution whose effects were to be studied. The nerve as it emerged from the solution was led across electrodes. At first platinum electrodes were used, but it was found that copper electrodes gave results identical with those obtained from the platinum electrodes, hence the use of copper ones was continued. This is contrary to general opinion, but control nerves remaining in Ringer’s solution showed practically no decrease in irritability, even after twenty hours, so injury from copper electrodes did not occur to any extent. The remaining portion of the nerve with the attached bit of spinal column was placed in a second paraffin cup containing Ringer’s solution. The entire nerve varied from 7 to 10 em. in length. The cover of the moist chamber was not removed during the experiment, which was often continued for sixteen hours. Every known precaution was taken for keeping the conditions as favorable as possible for the nerve, and as a result the controls in Ringer’s solution, run with the daily series of observations, showed very little change, if any, in irritability, even when the experiments were continued over a space as great as eighteen or twenty hours. Two Edison primary batteries attached in parallel, and renewed from time to time, furnished the current for the primary coil. The coil used at the University of Chicago was of the small type for labora- tory use, put out by C. H. Stoelting Company, Chicago. The greatest distance between coils on this type was 21.4 em. The coil used at the University of Minnesota was put out by W. Oehmke, Berlin. The coils could be separated as much as 75 em. with this type. Various types of keys were tried out, and the one most suitable was an ordinary wall-switch, conveniently mounted, which apparently gave a constant QUANTITATIVE STUDY OF EFFECT OF SALTS ON NERVE 503 break shock. The greatest distance between the coils just effecting stimulation was determined at regular intervals. The increase in the strength of shock, as thus determined, was assumed to be a measure of the toxicity of the salt. The writer recognizes the criticisms of such an assumption, but knows of no improved method at present. The salts were repeatedly recrystallized and the purity carefully tested. Redistilled water from a block tin condenser was used in making up the solutions. The data for purification are given in de- tail. The calcium chloride, C. P., was not recrystallized. About 45 grams were dissolved and made up to 250 cc. Then 10 cc. of this solution were diluted to 250 cc., and 50 ce. portions were evaporated and dried to constant weight in Jena dishes. Two samples weighed 0.3114 and 0.3116 gram respectively. This material was then redis- solved, heated, and ammonium hydroxide and ammonium oxalate added. The material was kept on the steam bath over night. After filtering and washing, the precipitate was ignited to CaO in platinum crucibles. On drying to constant weight, the CaO weighed 0.1569 and 0.1568 respectively. Then 111: 56.1 :: X : 0.1568 X = 0.3102 gram CaCl. The actual weight of CaCl, was 0.3114, the calculated weight 0.3102 gram, therefore, the impurity was 0.3 per cent. The potassium chloride had been recrystallized by Miss M. Koch. About 38 grams were dissolved and made up to 250 ce.. Of this, 10 cc. were diluted to 250 cc., and then 25 ec. portions taken for analysis. These were evaporated and dried to constant weight in Jena dishes, and two samples weighing respectively 0.1351 and 0.1352 gram were used. This material was then dissolved, potassium chromate added, and titrated with standard AgNO;. The amounts of AgNO; required were 11.27 cc. and 11.28 cc. respectively. The factor of the AgNO; was 1.607. Then 11.27 X 1.607 X 0.00746 = 0.1351 gram; 11.28 x 1.607 0.00746 = 0.1852 gram. As these were identical with the actual weight, the salt was 100 per cent pure. The sodium chloride was recrystallized four times. Five cubic centimeters of the stock solution were diluted to 250 cc., and 25 ee. samples were taken. The two samples were evaporated in Jena dishes and dried to constant weight. They weighed 0.0891 gram. This - material was dissolved and titrated with AgNOs, using potassium chromate as an indicator. The amount of AgNO; required was 9.58 ec. Then 9.58 < 1.607 * 0.00585 = 0.0900 gram. The actual weight was 0.0891 gram, hence there was 1.0 per cent impurity. The sodium bromide was recrystallized four times. About 28 grams 504 ESTHER GREISHEIMER were dissolved and made up to 250 ec. Of this stock solution 10 ee. were diluted to 250 cc., and samples of 25 cc. were taken. The samples weighed 0.1093 gram, on evaporating and drying to constant weight. The material was dissolved and titrated with AgNO;, 6.79 cc. being required for the titrations. 6.79 * 1.607 X 0.6103 = (0.1123 gram. The actual weight was 0.1090, hence the impurity was 2 per cent. The sodium sulphate was recrystallized four times. About 75 grams were dissolved and made up to 500 ec. Of this, 10 cc. were diluted to 250 ec., and 25 cc. were evaporated and dried to constant weight. The samples weighed 0.1417 gram. This was dissolved, heated and pre- cipitated by adding BaCle. The precipitate was filtered, washed and ignited to constant weight. The actual weight of BaSO; was 0.2335 gram. The calculated weight — (142.16 : 233.46 :: 0.1417 : X) was 0.2327. The impurity was therefore equal to 0.3 per cent. The rubidium chloride was made from rubidium carbonate. After several recrystallizations, about 32 grams were dissolved and made up to 250 ce. Of this 1 cc. portions were evaporated and dried to con- stant weight. The samples weighed 0.1261 gram. This was dis- solved and titrated with AgNO3;; 10.59 cc. were required for the titra- tion. The factor for this AgNO; was 0.985. 10.59 * 0.985 x 0.012095 = 0.1261 gram hence the salt was 100 per cent pure. The rubidium bromide was recrystallized three times. About 45.5 grams were dissolved and made up to 250 ec. Of this 1 ce. portions evaporated and dried to constant weight. The samples weighed 0.1787 gram. This material was dissolved and titrated with AgNOs, using 11.27 ¢c. in the titration. 11.27 x 0.985 * 0.016546 = 0.1836 gram. Hence the impurity of the rubidium bromide was 2.7 per cent. The rubidium sulphate was recrystallized three times. Five cubic centimeter portions of the stock solution were taken, evaporated and dried to constant weight. The samples weighed 0.1807 gram. This material was dissolved and precipitated with BaCl.. The precipitate, after standing on the steam bath for twenty-four hours, was filtered off, washed and ignited to constant weight. The BaSO, weighed 0.1568 gram. The theoretical weight was (267.06 : 233.46 :: 0.1807 : X) 0.1579 gram. Hence the impurity of the salt was 0.7 per cent. This is given in detail because the writer feels that physiologists generally do not realize the importance of having pure salts to start with. The salts most extensively studied were the chlorides of sodium, calcium, rubidium and potassium. Fewer observations were made on sodium and rubidium sulphates and sodium and rubidium bromides. The sulphates of sodium and rubidium and the chloride of caletum were —_—— . | } 4 ; ‘ QUANTITATIVE STUDY OF EFFECT OF SALTS ON NERVE 505 used in twelfth-molar concentration, but all others were used in an eighth-molar concentration, unless otherwise stated. Assuming that salts composed of a monovalent cation and a monovalent anion dissociate into two ions, and those composed of either a divalent cation or a divalent anion dissociate into three ions (as CaCl, or Na SO.) an eighth-molar solution of the former is approximately isotonic with a twelfth-molar solution of the latter. The solutions must be isotonic rather than equimolecular, for work on nerve. In the early period of the work records were kept of the muscular twitchings, but these were discontinued after a time, since they gave no additional information. The results of a large number of experi- ments were averaged. In spite of the current opinion that there is nothing constant about nerve work, the writer believes that a fair de- gree of constancy may be obtained if reasonable precautions are taken. RESULTS 1. Isotonic salt solutions Sodium salts. With % sodium chloride the latent period was two to three hours, and the period of contractions lasted about three hours. _ The contractions occurred as single twitches, and relaxation followed each contraction, with short periods of inactivity between the suc- cessive twitches. The irritability dropped considerably at first, then increased again, before the final fall. Fifty-two experiments were done for the three-hour period. As these were done at the University of Chicago, they were tested by the small induction coil, which was arranged to read at a maximum of only 21.4 cm. between the coils. Of course, no decrease in irritability was shown by this coil, so a straight line may represent the results, as shown by curve A, figure 1. Quite a different picture is obtained when a larger coil is used. The coil used for the experiments carried out at the University of Minne- sota was arranged to allow a maximum distance of 75 em. between the coils. Twenty-five experiments were carried out with this coil, and table 1 shows the results for a period of twenty-two hours: TABLE 1 A 0 3 1 2 3 5 7 8 9 13 22 B | 63-3 | 31.8 | 24.7 | 27.6 | 39.4 | 43.9 | 61.7 | 40.5 | 39.1 | 31.7 | 12.3 @e 168.0 | 62:5 | 26.5 | 33:5. | 68.0 | 73.0 | 7L-0 | 72.0 | 75.0 | 39.2.) 31.0 yy Sr-5 22.0 | 21.0) 20-5 | 15.0: [13.5 45.7, |) Saeed, | 220) a0 506 ESTHER GREISHEIMER As it is impossible to give all the readings for all the nerves, only the average, the maximum and the minimum readings are given in the table. N } Mees I Fig. 1. A -= NaCl; B= ~ CaCh, table 4; C= = KCl, table 6; D= = © RbCl, table 8. Abscissae—time in hours. Ordinates—distance in ems. between coils. M M 3 M ) Fig.2. A= = NaCl, table 1; B = rs CaCl, table 5; C = & KCl, table 7; M D= Fi RbCl, table 9. QUANTITATIVE STUDY OF EFFECT OF SALTS ON NERVE 507 A indicates the time in hours; B, the average readings of the twenty- five experiments; C, the maximum reading of the nerve showing the greatest irritability; D, the minimum reading of the nerve showing the least irritability. The extremes are variable, as shown by the table, but it must be borne in mind that the majority of the nerves were near the average degree of irritability. Of the twenty-five nerves, two had become non-irritable within twenty-two hours. Curve A, figure 2, indicates the results obtained for the longer period. The abscissae represent the time in minutes or in hours, as specified, and the ordinates indicate the distance in centimeters between the primary and secondary coils. With ¥ sodium bromide the stimulation was less than with ¥ sodium chloride. No experiments with sodium bromide were done on the large coil, but the average for those done on the small coil is shown in table 2. TABLE 2 TIME 0 3 1 2 3 4 5 7 12 PN ETA SO 2, wes ee 21.4 | 21.4 | 21.4 | 21.4 | 21.4 | 21.4 | 19.6 | 17.6 | 12.8 Maximium,.......-.| 2:4 | 2194 | 204 | 20-4) 21.4 | 21.4) 21.44 21.4) 2.4 Minimum... .\......-<'. 24s 20 4e POS 20 ae 2 an? 214s | onee | orl |e 22 Only nine experiments were carried out with this salt. No com- parisons can be made with the other sodium salts respecting the original drop in irritability, since the small coil did not register this. The bromide is evidently more toxic than the chloride, as shown in curve B, figure 3. Sodium sulphate in ;'5 concentration was more toxic than either the chloride or the bromide. The latent period of stimulation was from ten to twenty minutes, then prolonged low tetanus continued from one to three hours. The decrease in irritability was more rapid and greater than in the other sodium salts. The results of thirty-two experi- ments with the small coil are shown in table 3. The greater toxicity of the sulphate is believed to be due to the sulphate ion, rather than to the higher sodium ion concentration. In the Hofmeister series sulphate is more effective than chloride, in many physical systems, so we expect it to behave as it does in physio- logical systems. Its toxicity is shown in curve C, figure 3. 508 ESTHER GREISHEIMER TABLE 3 2 ees eee TIME 0 3 1 13 2 23 3 5 7 12 Average..............+.| 21.4] 20.9] 20.9] 20.5} 19.4) 18.2) 15.1) -7.6) 5.2) 2.7 Maximum..............| 21.4} 21.4] 21.4] 21.4] 21.4] 21.4) 21.4) 20.0) 19.2) 14.5 Minimum’) -222.:.0..)21.4/ 1 8.5).07271720! (5. 8)od8h 20 Or tO ae Fig. 3. A=~ NaCl; B= NaBr, table 2; C= <5 Na,SO,, table 3 Calcium salts. The chloride was the only calcium salt used. In 7 concentration it did not stimulate the nerve, but it did produce a medium decrease in irritability. Mathews (28) states that sodium salts are necessary for the maintenance of irritability of the nerve. The author found the nerves still irritable after being immersed in calcium chloride for sixteen hours. Calcium chloride occupies a position between sodium on the one hand, and rubidium and potassium on the other, in respect to its depressing effect. Sixty-six experiments were carried out with the small coil for three hour periods. The results are shown in table 4, also in curve B, figure 1. TABLE 4 TIME 0 50 | 60 90 120 150 180 Magid. Sade ded 21.4 | 18.8 | 17.1 | 14.8 | 12.6 | 11.7 | 10.4 Maximum... cools :isie succes ostoa del 214) | 21.4 | 2be4, | 21,26) 2194 ot ies IAN IEAUT ee yc) eee ee ee | 7.3.1 6.0 | 634) 6.0:\ 3:0 aee QUANTITATIVE STUDY OF EFFECT OF SALTS ON NERVE 509 Twenty experiments were carried out with the large coil for long periods. The results are shown in table 5, and in curve B, figure 2. TABLE 5 Average........ 63.3 18.8/17.1/12.6)10.4| 9.7) 9.6) 9.7) 9.4)10:8)/10.5|10.3) 8.9) 7.3 Maximum...... 75.0/21 4/21 .4/21.4/18.8)18.1/15.6) 9.0/17.1)16.4/15.9)15.0)14.0)14.0 Minimum...... 59.0| 7.3] 6.0] 6.0] 3.0| 3.6 2.9 2.5) 3.0, 3.0] 3.0, 3.0 2 -OFE0 Thirteen out of twenty were still living at the end of fourteen hours, and three out of six were living at the end of eighteen hours. Potassium salts. The chloride was the only potassium salt studied. An = solution of potassium chloride was found to be a stimulant of the nerve, contrary to the observation made by Mathews (1). Eighty- seven experiments were carried out on this salt alone, and in about 80 per cent of the cases, stimulation occurred. The latent period was from ten seconds to one minute, and the contractions continued from two to four minutes, rarely longer. This stimulation may have been overlooked by previous investigators, but that it was due to the potassium chloride is shown by the fact that it occurred with no other salt. The decrease in irritability was rapid, and the results certainly show that rubidium and potassium chloride are similar in their toxicity effects (consult curves C and D, figs. 1 and 2). Table 6 shows the results for three-hour periods, of eighty-seven experiments. TABLE 6 TIME 0 30 60 90 120 150 180 PARVET ASCHER ee kites SLAW D2 ou OW LOL Ze OeAae SAN iia: WU RITATEET iors cack fen cmeoics:. « QUA 214 ZOE 2a 212 SES P1822) | Tore Vitamin ec ce 2 hsv. Sacearse eee ea Le Al OR ete Oa RO! herr || 8.7 )|, Saf), 9. 7 SG ae This shows that the isotonic solution preserves a slightly higher irritability than the hypotonic solution. These experiments are by no means exhaustive, yet they indicate that isotonic solutions are less toxic than hypotonic, or that osmotic pressure is a possible factor in maintaining the irritability of nerves in various solutions. 4. Salt antagonisms A series of investigations was made with combinations of two salts, for the purpose of testing the so-called antagonistic action. For these investigations 1 part of ¥ calcium chloride and 99 parts of | sodium, potassium or rubidium chloride were used throughout. Twenty- one long experiments were carried out with the mixture of calcium and sodium. Undoubtedly the calcium chloride in this concentration had some antagonizing action, as shown in tables 1 and 20 and in curves A and B, figure 9. bd . QUANTITATIVE STUDY OF EFFECT OF SALTS ON NERVE 517 Fig. 9. A= = NaCl, table 1; B = 99 parts : NaCl, plus 1 part z CaCl, table 20. TABLE 20 TIME 0: ls 1 2 3 Bille 8 9 10 | 12 Average..........| 63.3} 60.9] 60.8) 61.4) 62.0} 59.8) 57.1) 56.9) 53.0} 49.9) 48.0 Maximum........| 75.0) 68.5) 68.5] 68.5) 69.0} 69.0] 65.4) 66.0} 67.0; 66.5) 69.5 Minimum......... 52.5) 52.5] 53.0! 53.0] 55.0} 51.0} 44.0} 35.0 25.5 9.0} 4.2 The initial fall in irritability in ¥ sodium chloride is prevented by the addition of a small amount of calcium, and even after twelve hours the nerve in the mixture is much more irritable than the one in sodium chloride alone. This surely indicates a protective action of some kind on the part of calcium. The picture obtained by using 1 part of ¥ calcium chloride and 99 parts of ¥ potassium chloride is quite different from the above picture. Twenty-three experiments were carried out with this combination. The calcium here played a minor réle, and its protective actiqgn was not a decided one. The results are shown in tables 6 and 21, and in curves A and B of figure 10. The decreases in irritability of the 518 ESTHER GREISHEIMER two series were similar, the addition of calcium being slightly beneficial. TABLE 21 TIME 0 a 1 2 3 Average: {55 os bes vada. 2 bee bebe: Sos hee) Od535) 149s etee sy SOP eae Maximum: .. . : PAINS (25) ZWAARDEMAKER AND Beene Kon. Akad. von Wetanschappen, 1916, XxV, 517. (26) Henrior: Chem. News, 1911, civ, 47. (27) Kocu: Zeitschr. f. Physiol. Chemie, 1902, xxxvi, 134. (28) Maruews: This Journal, 1904, xi, 455. (29) Crowns: Journ. Phys. Chem., 1916, xx, 407. THE PRACTICABILITY OF FEEDING A SCIENTIFICALLY BALANCED RATION IN ARMY CAMPS R. J. ANDERSON From the Section of Food and Nutrition, Division of Sanitation, Medical Department, U.S. Army Received for publication June 3, 1919 The proper feeding of an army or of army divisions, such as were in training in numerous camps throughout the country during the past year, presents several important problems. First of all available food sup- plies must be considered. Those furnished by the Subsistence Branch of the Quartermaster’s Corps constitute the Garrison Ration Articles. Certain supplementary articles may be obtainable in the local markets or adjacent territory. Equally important are the matters of storage, the prevention of spoilage and the cooking of the raw food products into edible and nutritious food. With ample food supplies available, ‘those responsible for the feeding of the army must select such com- binations of food as will safeguard and maintain the health of the troops and increase their vigor. In this selection it is necessary to consider the relative proportions of protein, fat and carbohydrate, and perhaps also the acid and basic elements contained in the food, together with so-called vitamines, which should be supplied for a properly balanced diet. In addition to the above a satisfactory diet must also contain a certain amount of roughage or indigestible residue. It is self-evident that a group of men cannot subsist upon calories alone, but upon nutritious and wholesome food containing an adequate amount of nourishment for the bodily needs of repair and supplying sufficient fuel value in addition for the performance of such work as may be required. Unless these conditions are fulfilled the men will become dissatisfied, the morale will be lowered and the efficiency of the organization will be decreased. In ordinary life people of ample means choose their food according to taste and appetite. The selections which are made are usually sufficiently varied to furnish an adequately balanced diet. It not in- frequently happens, however, among the poor and ignorant that a 523 524 R. J. ANDERSON thoroughly inadequate diet is either selected or thrust upon them by necessity, with resultant serious disturbances in health and vigor. In the army the men can not choose their own diet. The food is placed before them in the mess and they may either eat it or leave it. It is therefore of the utmost importance that the food supplied be properly and wisely selected and also that it be prepared so as to preserve or increase its nutritious and appetizing qualities. In considering what constitutes a balanced diet we must bear in mind what was said above, that men do not live on calories Alone. Frequent changes of menu and as great a variety of food as possible are not only desirable but necessary. It would be very easy to supply an adequate number of calories to any group of men if but little attention were given to variety, but it requires more care, experience and planning to furnish the necessary number of calories in a well- balanced diet upon which men can subsist to advantage for long periods. All of the troops in the new armies in training camps in this country during the recent emergency were fed on the basis of the Gar- rison Ration and all of the messes enjoyed the privilege of ‘Ration Savings.’’ In addition to the Garrison Ration articles extra-ration food supplies, such as fresh vegetables, fruits, eggs, etc., were usually purchased by the mess sergeants in the local markets and were paid for out of the ration savings. The Garrison Ration formed merely the basis upon which the cash value of the ration allowance was cal- culated, each organization receiving money credit for the number of men entitled to ration multiplied by the ration allowance. The money value of the ration allowance varied from month to month and from camp to camp, depending upon prevailing food prices. Against this money credit the organization drew at certain intervals such Garrison Ration articles as were needed during the month. The amount of the total food supplies thus drawn by each mess from the Quartermaster varied within rather wide limits (from about 65 to 90 per cent of the ration allowance) and it varied from camp to camp, depending upon local camp regulations as well as upon local market conditions. Under army regulations in effect April 1, 1919, all of the food used by troops must be purchased by, and supplied through, the Subsistence Branch of the Quartermaster’s Corps. The ration savings privilege has been revoked, all savings reverting to the Government. However, 25 per cent of the ration allowance may be expended by the Camp Supply Officer in purchasing extra-ration articles. The success of this system will depend, of course, upon the ability of the Supply Officer to obtain SCIENTIFICALLY BALANCED RATION IN ARMY CAMPS 525 all of the articles called for and in sufficient quantity to fill the demand. Even under the old system a month seldom passed when the Subsistence, Branch was not out of certain products for a longer or a shorter period. Foreed issues of various food products which were overstocked and therefore likely to spoil were also not uncommon. On the whole however, the new system has much to commend it. The purchase of all food supplies is centralized in one office, which should lead to much desired efficiency as well as economy in feeding the army. The outstanding disadvantage is that perishables can usually be purchased most advantageously on an opportunistic basis. Under army regulations the company commander is responsible for the proper feeding of the men. In actual practice, however, it was frequently found that this duty was left largely, if not entirely, in the hands of the mess sergeants. Occasionally, however, mess officers and company commanders took a lively interest in the mess conditions of the men. In such cases results were more satisfactory than when the mess sergeants were largely left to their own devices. Often one could tell by mere inspection of the messes whether the commanding officers gave them their personal attention. As has been indicated above, the amount of food consumed and the proportion of the different nutrients in the diet varied greatly in dif- ferent messes in a camp. It could hardly be otherwise when we con- sider the enormous expansion of the army within a few months and the lack of training of the new soldiers in matters pertaining to dietet- ics and cooking. Mess sergeants and cooks frequently were ‘“‘made”’ through necessity by orders of the company commanders. It is not to be wondered at, then, that many of the messes were run on a hit-or- miss plan, so far as a successful diet was concerned. Even after the mess force had had several months’ experience it was not unusual to find that the average food consumption varied by 1000 or 1500 calories per man per day in adjacent companies in the same regiment. Good cooking and high food consumption appeared to stand in direct relation. The activities of the Schools for Cooks and Bakers naturally helped to improve matters somewhat in the long run. The commanding officers of these schools were zealous and industrious but their knowledge of dietetics was very limited. Their instruction in mess accounting, on the other hand, was adequate. On the whole these schools succeeded in working marked improvements in mess conditions. No matter how carefully the food material is selected and the menus calculated, a successful diet can not be maintained unless provision 526 R. J. ANDERSON is made for the proper preparation and cooking of the food. The finest raw material may be ruined by poor cooks. There is, therefore, urgent need to continue schools for cooks and bakers in the army. In order to turn out competent workmen, however, it will be necessary to give the students more thorough instruction in the art of cooking than was generally given in the schools during the past year. Many of the so-called graduate cooks who were turned out were fairly well instructed in the duties of the kitchen police, but the number who actually knew how to cook food was unfortunately small. Personal observation in several camps during the past year showed plainly the need of a more centralized and effective control over mess conditions than existed at that time. From the standpoint of efficiency, dietetic as well as financial, the practically independent operation of some 200 to 250 messes in a camp cannot be considered successful. Some one with sufficient authority should have sufficient general super- vision over mess conditions to insure that adequate variety of food be provided. The making of menus for the different organizations should also be supervised in order to insure the proper combination of food-stuffs in the diet. In the past the menus were frequently made out by the mess sergeants one day at a time and the foods thus supplied depended largely upon what was on hand or on what could be immediately obtained. Much better. results would be secured if tentative menus were made out for a period of, say, ten days inadvance; purchase could be made then in accordance with the requirement of the menus. At the present time we possess sufficient knowledge regarding the composition of raw food material to calculate in advance any desired diet. We can also provide adequate variety of fresh vegetables and fruits, which will supply sufficient roughage and necessary basic elements as well as vitamines. Some of the latter should undoubtedly also be furnished in the form of fresh butter. It may remain an open question just how much food should be furnished to each man, but the aim might well be to provide on an average about 3600 calories (net) per day for men doing moderately hard work. Some men will consume more and others less, depending upon bodily condition and appetite. Careful consideration should be given to the proportion of protein, fat and carbohydrate contained in the diet. The arbitrary selection of a standard may be of doubtful wisdom. On the other hand, standards itemized by means of statistical studies need not be taken as infallible guides. It has recently been SCIENTIFICALLY BALANCED RATION IN ARMY CAMPS GPa proposed by the Division of Food and Nutrition to aim at furnishing the following balance: Protein, 12.5 per cent, a quantity known to be adequate; fat, 25 per cent, the amount being intentionally re- stricted on economic grounds, and carbohydrate 62.5 per cent. Before definitely selecting any standard balance for the army it might be advisable to conduct careful experiments over relatively long periods of time in order to determine what diets actually give the most satis- faction to the men and which, from a physiological as well as an economi- cal basis, are the most desirable. A diet containing only 25 per cent of fat might be less satisfying than one of higher content. Besides, if a reasonable amount of fresh butter is provided it is difficult to keep the fat content under 30 per cent. In this connection it is interesting to note that all officers’ messes, cadets’ messes in aviation fields and student officers’ messes in Camp Greenleaf, in which dietary studies were made, supplied 40 per cent or more of the total calories as fat. These messes appeared to furnish a diet which corresponded more closely to the usual civilian or family fare than was furnished to enlisted men. A considerable part of the fat in these officers’ messes was derived from the butter which was used according to taste at the table. Enlisted men received, as a rule, very little butter. Food which is well cooked and which contains the higher percentage of fat is undoubtedly the most appetizing and satisfying. We believe that it would be for the interest and welfare of the army if some officer trained in the science of nutrition and in practical dietetics weré connected with each camp or army’ division. The officers selected for this purpose should be men of thorough prac- tical training in the army and possessing, in addition, full knowledge of the composition of food and the science of nutrition. They should be particularly well acquainted with the practical side of nutrition and the problems involved in feeding large groups of men. An effort has been made in recent months to fill this want by appointing nutri- tion officers to serve in camps in this country. If nutrition officers are to form a permanent addition to our new army, men of the qualifications mentioned above should be selected. They should be at least coér- dinate in rank with division sanitary inspectors. Nutrition officers of subordinate rank will have a limited field of usefulness and they will with difficulty be able to accomplish much in the way of fundamental improvements. Unless matters pertaining to nutrition be placed under the super- 528 R. J. ANDERSON vision and control of men thoroughly qualified on both the theoretical and the practical sides, one may well doubt the practicability of feeding a scientifically balanced ration in army camps. The only alter- native would be to maintain a separate Department of Nutrition or Alimentation in connection with the War Department in Washington, with subordinate officers in the camps who could carry out orders from the Washington office. In connection with the feeding of a balanced ration in view of the new system of supplying all food through the Subsistence Branch, one might suggest in the interest of good nutrition as well as to aid the camp supply officer, that a uniform menu be adopted for the whole camp. This should be done, however, only under the direction of competent authority for it is realized that a uniform menu, unless carefully prepared and supervised, might lead to very unfavorable conditions and a stereotyped form of diet. The menu should be made out from ten to fifteen days in advance in order to give the supply officer an opportunity to secure the necessary raw material. Unless some such scheme is adopted the men will have to subsist upon such food supplies as are available at the subsistence store from day to day. The menus should specify the amount in pounds of the different food- stuffs to be actually used each meal for a given number of men. When this is done, having due regard to the composition of the food material, a diet of any desired composition or balance can be provided. In this way a scientifically balanced ration can be furnished an entire camp almost as easily as for a squad of men in an investigational laboratory. The results of the dietary studies in army messes made by Survey Parties of the Section of Food and Nutrition, to which reference has already been made, showed that numerous nutritional errors were committed which could easily be corrected if proper supervision over mess conditions were maintained. For example, we reproduce below the result of two dietary studies made early last fall. One mess consumed on an average the following quantities per man per day: PERCENTAGE eevee te DISTRIBUTION OF CALORIES Propeninn 55 1 pawl cn eoeteate Mase Es al | a eae: one ee 85 12 Carbohydrate. 5.)...) Se aue cue oan Re nee oe 472 68 Total calories about 2830. SCIENTIFICALLY BALANCED RATION IN ARMY CAMPS 529 In an adjoining organization in the same camp and at the same time of the year where the men did less hard work, the following amounts were consumed: PERCENTAGE OF DISTRIBUTION OF CALORIES GRAMS [PRG Tae A a RCE A CRE ORE Ste ene er 131 13 LEMP oy cues Gro STS ey Se SE tele gD es Dee he a dia es 145 33 MERMPIAEISCLE SLC CR hes SEY, 8 3 nis diay 3 oid Bos Bef ars Site's <3 eo 540 54 Total calories about 4100. Both of the above messes were well managed and the mess sergeants were above average ability and they had had considerable experience. In the latter mess the men were receiving more food than they required for the very light work which they were doing. In the former the men were decidedly underfed. But the men in both organizations were under the impression that they were well fed. In the first mess liberal quantities of cabbage, sauerkraut, onions, turnips and potatoes were supplied, which made up a large bulk of low fuel value. This is not an isolated instance but many messes were studied in which considerable degrees of disparity were observed. What must be especially guarded against is the excessive use of canned goods instead of fresh vegetables and fruits, and the too frequent employment of the cheaper meat products, as was frequently noticed during the past summer. When one remonstrated against this form of diet the statement was always made, ‘‘ Fresh material cannot be obtained.”” Under the new ration system the supply officer, in handling the large demand for an entire camp, will be in a position to draw on distant markets for many articles which are not obtainable locally. This would apply particularly to vegetables, fruits and fish. As an aid and a step in the direction of correcting dietary errors, such as those mentioned above, the adoption of a uniform menu, prepared under the supervision of an expert in nutrition, seems worthy of trial. The menu might be prepared in a conference between the nutrition officer, mess officers, mess sergeants and the supply officer. Such conferences might be held every week or ten days. This arrangement would also serve to coérdinate mess consumption with available food supplies. THE AMERICAN JOURNAL OF PHYSIOLOGY, VOL. 49, NO. 4 530 R. J. ANDERSON The hearty codperation of the nutrition officers, mess officers and other mess personnel, and all others concerned with handling the army ration, will be required to bring about the best nutritional con- ditions in the army. Some one with thorough training in nutrition and practical dietetics should be authorized to supervise the diet for the whole camp in order that a scientifically and correctly balanced ration may be provided. AVERAGE FOOD CONSUMPTION IN THE TRAINING CAMPS OF THE UNITED STATES ARMY JOHN R. MURLIN anv F. M. HILDEBRANDT! From the Section of Food and Nutrition, Division of Sanitation, M edical Department, United States Army Received for publication June 3, 1919 One of the main objects of the Division? of Food and Nutrition of the Medical Department of the Army was to determine the actual food requirements of soldiers in active training. Beginning October 1, 1917, and continuing until December 1, 1918, nutritional surveys were made in 67 different camps including 49 divisional and other . large concentration camps, 14 aviation fields, 3 war prison barracks, 1 recruiting station and 1 spruce production camp. Twenty-six of these camps were surveyed a second time and three of them a third time. The total of individual messes included was 458. Upon re- calculation of results in the Washington office, errors were found sufficient to exclude from the final report 31 of these messes, leaving a total of 427 which could be accepted as exhibiting the necessary care and control. From time to time as the statistical reports were received from the nutritional survey parties averages were compiled for 49, 68, 85, 143, 185, 213, 361 and finally 427 messes. Table 1 shows the average amount of food supplied, wasted and consumed on the man per day 1 The following officers, as leaders of nutrititional survey parties, contributed to the results here summarized and vouch for the accuracy of the reports: Majors Walter H. Eddy, Frank C. Gephart, Roy G. Hoskins, H. A. Mattill, J. Garfield Riley and John P. Street, all Sanitary Corps, and Majors Don R. Joseph and Caspar W. Miller, Medical Corps; Captains R. J. Anderson, N. R. Blatherwick, J. F. Brewster, Henry R. Cates, Arthur W. Dox, Paul E. Howe, F. B. Kingsbury, M.G. Mastin, Arthur W. Thomas and Drury L. Weatherhead, all Sanitary Corps; and Lieut. T. A. Wayland, Medical Corps. 2 The Division of Food and Nutrition was established as a separate Division by authority of General Order No. 67, W. D., dated July 15,1918. After December 2, 1918, this order was tacitly disregarded and the Division became, for conven- ience in administration, a section of the Division of Sanitation. 531 JOHN R. MURLIN AND F. M. HILDEBRANDT 532 punod ZF "0 punod 78 °0 $}U99 66% 8}U909 JT CP punod FF'0 punod ¢g°0 sjued OLS syuo0 CG’ GP punod ¢F°0 punod 780 87U00 Th € 8}U99 8¢ TP punod ¢p'() punod 780 sjueo [G'¢€ $}U99 ZS OF punod —-— punod —-— szu90 2G°E By U00 6S LV sere OISBM O[QIPA reese ses gagBM 1840], segmereaete ss keN SOD O}SB MA see ee eee 4800 poyddng ‘OYSUM O[QIPA Bee MSGI (at ee alah cise ie ee eee eee 4800 porjddng “++ -998uM OLqIPTL Fees gg gBAN [RIOT see Eee ca SOD) O4Se MA eee renee 4800 porddng seen a}SBM I[QIPH pee EUSA [ERO See ee EATA ROD) O4SB AA eee ee eee 4800 porddng rss QaseM OTqIPE Fert e ss gag@aN [BIOT, Freese sss -qg00 OSB AA *ysoo potpddng AVd Udd NVW Had roocr S ise) OOT ~eoor No) uD OOT L 9¢ IT O& 6 tI quao sad| 7ua0 wad Ag 40 daLsvM| “ULsia aqaWoOsNnoo pouns -u0y 166 STE Poqse yy PFOE 62S ene “s'SortopBo fan[BA [ONT “sures ‘oyerpAyoqiey nike -8| ete e)aiia) sue (a a lepseue ler surels ‘4B 7 Oa ON GZOVOR RIOR OIMNOFSY 9 9 (299 br | ‘uleyO1g +t oe SG RT TOTED ‘On[Ba [Pn sureis ay OL SERA OSES) “survas ‘y RB iT tr aigsiia) alee! 390 sured ‘UI0}0.1g "rs SoTIOTBo ‘ONTBA [ONT Sues Boy eu paren tg “--gureid “yey estos CaO suvas ‘UloyO1g “"“So1lo[eo fonyBA [on sureis ‘oyeipAyoqiey O00 SO 6.0% Oo sures ‘Qeq OID DINOS y pM tr] ‘Ul94O1g fist Ose aT TCT BO ‘an[Ba PQ sues NP “suIvIs “4BiT “sureid ‘uloJO1g | | : | | SOSSOUI GRT SOBBIOAYV SOSSoUl EFT SODBINOAV SOSsoul Gg SOBRIOAY SOSSoUL QO SODBIOAY SOSSOW GF SODBIOAYV SPUOLIFN NT AVd Udd NVW UAd dood T AIAViL sdwpo Bururva) ur pawnsuod hbuvwa pup s7Uar4yn NV 533 AVERAGE FOOD CONSUMPTION IN ARMY TRAINING CAMP punod gg'9 **" 93SBM 9[qIPoT punod 080 agen Rees SOS 1830], syuaaoge co 4809 048% AA ATUS9!O0i fh es ysoo payddng punod of'Q °°" °*** *{a4s@M a[qIpry punod 9g°Q °°" ** "*"94SBM [BOT Sue gpee °°" SF . “S00 2488 AA sila yay (gpa BODOG ysoo porddng punod gp *" 7" "7" 098BM O[GIPA punod E8'0 °° OIseM [BOT squa0 0O'@ °° °° 7774809 OSB AL $}U00 GJ Zp °°°°"' 4800 partddng ~oort eo Rie ) ~roorty OOT OOT Cae ppetoleg ‘an[Ba [ony Ope) |e: “sulvisd ee ATO Rt: He) 2 | bola ae ; “suBtd (4B T Igt Be) sd) a ee ene 6 6 e e185 survid Ul} 01g GES Pee = Mv tp ‘on[Ba [en CTC estes ‘suUBIS ‘978. ee) O&L Sy) Ch Oe ha yO CnC CEO Che sured ‘ nWeH § EST Ce ee sures ‘ule O1g eg6e | 7 Setaoyeo ‘onyBa jong leg [occ surers ‘oye1pAyoqiey eel ele © aoa ogee Sos lle erg ee aan, Sel pie Siete sismime* ° g ° 8 ° 8 5 Sas cm 538 JOHN R. MURLIN AND F. M. HILDEBRANDT THE EFFECT OF SEASON ON FOOD CONSUMPTION It is a familiar fact that one eats more food in winter time than in summer and particularly more of the foods which stimulate heat production most, viz., meats. Few dietary studies have been made in a carefully controlled manner, however, which exhibit with certainty this seasonal variation, and so far as known to the writers, none at all made on bodies of men engaged in the same form of physical exercise. Chart 3 exhibits the average food consumption month by month from October, 1917 to December, 1918 as determined by nutritional surveys in the training camps. The number of messes included in each of these months, however, is significant only from the month of November, 1917 to the month of September, 1918. It will be noted that there is a gradual increase in food consumption from November to March, after which there is a sharp decline which continues throughout the summer. Attempts have been made to correlate these variations with the average temperatures prevailing in the camps at the time of the surveys. This has not been wholly successful, probably for the reason that there is no known factor which will account for the cooling effect of winds upon the human body. In other words, food consumption does not vary inversely with the temperature in any simple relation- ship, for the effect upon heat loss, and therefore upon heat production indirectly, of a windy day in summer may be as great or even greater than that of a still atmosphere in winter. Wind velocities have been reported by the weather bureau stations in the vicinity of camps and attempts have been made to find some mathematical expression of the influence of winds upon food consump- tion as reported by the nutritional survey parties. The inherent error in the methods of a nutritional survey and the variability in food consumption depending probably upon the character of the cooking and service, or upon what may in short be called appetizingness of the food, are too great to exhibit the effects of the individual climatic factors. There remains, however, the seasonal variation shown in the chart which probably represents the combined effect of the various climatic factors. Thus on a priori grounds alone, one would expect a summation effect of low temperature, high wind velocity, high humidity and possibly high barometer. Of these, the variations in temperature doubtless are the most important, after which would probably come wind velocity and humidity, with the factor of barometric pressure occupying a doubtful position. ° a 9 ovo 09'0 og'0 AvVO Maa New wsaq (37107) B1Sw™ oar P2UO}ODPI34 US posSEqg YoP woat apoiu ycloub siyy : ajow Gi/v/< "190 & yey) shaaanc Kop 20d Uoursad BSOm {O {SoD --------- hop 3290 vou sad 250M WIP — — — Kopax! vow sad peudsLom poos parrddac poo} 4o Ropuecl vow sed ycoo — --— eibi Lib mae sawar AV Mav WwW ‘e34 NYC Jaa AOW ‘Loo PON fO001 (\ > y Oz 0002, * a : mM 7 u > POS? CODE y i 4 a y pOVs;COON) 4 1 v i i 2 = r 3 5 POs jooos 7 ; 3 3 2 3 a 3 3 2 : a mk % ° fe 4 ° 3 . fog sad uojaj aad aysoy aiqipy fo junouy ; ool puo pauinsuo’ p04 ye spre d\SOM puo Poot \o 189) SAaSvyAaAv ATH AN OW 539 540 JOHN R. MURLIN AND F. M. HILDEBRANDT How much of the seasonal variations in food consumption is due to the greater stimulus of atmospheric conditions to muscular work in winter time than in summer cannot be stated. In other words, the variation shown in chart 3 is certainly not a simple effect of tem- perature, but is complicated still further by the indirect effect of temperature upon muscular “willingness,” if one may coin such a term. Certain it is that one works with greater ease under conditions TABLE 2 Average by months per man per day FUEL EDIBLE Ot Gr weeds scerius - at as oes ae pounds October Moos pa ees Clete 3 37.72 | 3606 0.56 3.82 November, ally. cect pele poke ws ple 19 41.57 | 3706 0.57 3.31 December vlGl7 2 cca. keep oc ee ee ss 36 40.47 | 3819 0.41 2.58 JanuanyelOlSirn.- oneceyoe esos ee nae 37 40.85 | 3827 0.38 2.64 ME briany Ol say soccer aie creer 30 42.41 | 3864 0.43 3.24 Marche lois anata oo tecet acts 42 45.61 | 3894 0.23 2.99 Arori ls VOUS cava cata erceapar alert say oe aa 43.48 | 3545 0.34 3.02 Misys LOIS Ae aan Pion Sy Wye ee 30 42.15 | 3514 0.28 1.85 Sune, MOIS Ah oi. op capi. «oe eee 20 44.86 | 3517 0.44 3.62 fv bd C2 eee A et 2 A a, ee 13 41.89 | 3609 0.19 1.66 NGUSes LOIS: Foe ee ee eee Be 14 44.92 | 3658 0.14 1.14 September 1918 Wey ayes seis wee 8 47.64 | 3487 0.35 2.85 October <1 OISK 2. ae ee tet: 13 47.33 | 3727 0.23 2.42 November Gish ae .at parece peri u 7 46.14 | 3918 0.48 3.41 December LOWUSE oy. sets ss sited 5 57.56 | 4145 0.40 4.04 MOA 3 2 Mire,: hia eee See Sete 354 AV CTA CTS 5: 4. cB RC reer mer 44.30 | 3722 0.36 2.84 Above information recalculated from nutritional survey reports. All base hos- pitals, officers’, cadets’ and prisoners’ messes excluded. Cost supplied is average cost of food supplied per man per day. of low temperature, low humidity and high barometer; the effort of muscular work is less, consequently there are probably many gratul- tous muscular motions in the performance of any given piece of work. The tendency to frolic amongst soldiers is highest at such a time. All of these extra motions obviously would of themselves increase the heat production quite apart from the simple cooling effect on the skin, and would correspondingly increase the desire for food. AVERAGE FOOD CONSUMPTION IN ARMY TRAINING CAMP 541 In conclusion of this subject of seasonable variation it may be noted from chart 3 that the maximum difference between the average for the winter and the summer months is not more than 300 to 400 calories. The average soldier, weighing 146 pounds (after four or five months’ training) will consume, therefore, not to exceed 400 calories more daily throughout the winter months than in the summer months. Warmer clothing, heated barracks and warm bedding each play their part in keeping down heat loss. Chart 3 is based upon table 2. In addition to seasonal variation in food consumption this chart and table exhibit also the variation from month to month in the cost of food supplied per man per day; likewise the variation in the amount of edible waste and its value. One fact only of these additional curves will be mentioned at this place, viz., the influence of the armistice, which is apparent in the averages for food waste for the months of November and December, 1918. EFFECT OF LENGTH OF TIME IN CAMP A number of studies of food consumption in recruit organizations have been made. These are in agreement as showing that in the first few weeks of camp life the recruit does not consume as much food from the mess as he does after becoming thoroughly habituated tc camp conditions. In illustration may be cited chart 4, which represents a study made upon a recruit company at Camp Pike during the months of July and August, 1918. For three weeks the entire company was kept together, after which the men were separated into Class ““A”’ and Class “‘B” men. It will be noted that the food con- sumption beginning at about 2700 calories per man per day in the first week mounts successively to 3000 and 3100 in the second and third weeks respectively and by the end of the fifth week has reached the average for all messes of about 3600. The first two weeks in camp cover the period of inoculation for typhoid and paratyphoid. This, together with the strangeness of surroundings, particularly of the mess, menus, cookery, style of service, etc., and probably lack of digestive capacity, serves to keep down food consumption and is responsible for the noticeable loss in weight the first week. The weight is promptly recovered, however, by the end of the third week. — vy WVYO -hyudard proudhy -Kucloud Rea ret stie bes ky -—— uur 22 22 ie een GS WMeoM YWwuaarn | © MBM 2 WMOOM O He | UaW bd) uaw g@zi 7A. SSEVH1> Ww, SSW1D eet ‘ysoboyy Pan hyae bataap DMI duns yo apow SLINUDAY SO SANOUD OMA NI BSVvSwSH! LMS aan Sik NoOtleinnSswSes doow we amas *s,u5iam sev usr~we ‘can Sei ml 991 I ooo! rll @) oxi y 6 i r Ovi coozg 4, alll » 3 eel nm ooos V | ooo AVERAGE FOOD CONSUMPTION IN ARMY TRAINING CAMP 543 FOOD CONSUMPTION AT THE CANTEEN ‘The canteen, also called the “post exchange’ or regimental “ex- change,’’ is partly a social institution and partly a supplementary mess. Regulations governing the exchange in the training camps have been on the whole very satisfactory as regards sanitation and the inspection of food materials sold therein. It is naturally very difficult to keep a record on the man per day basis of food sold to a given organization at the exchange. The difficulty arises from several causes. In the first place, even if the organization has its own canteen, men from other organizations will make purchases there; also a single man may make purchases in the canteen for himself and a number of others. These things taken to- gether make it difficult to pro-rate the total sales for any period. Again, the general experience of field officers has been that the post exchange is patronized much more by the recruits than by soldiers who have become habituated to the mess. Consumption may thus vary from that of the raw recruit, who in many cases will live almost en- tirely on candy, ice cream and cake purchased at the post exchange, to that of the old regular army man, who limits his canteen purchases largely to tobacco and toilet articles. An average of sales from a single canteen without due account of these causes would be of little value. The average of a large number of such surveys, however, may be accepted as approaching the true average consumption of food from these sources. Altogether nutritional survey parties have reported 261 studies of food consumption from the exchange. Chart 5 represents for 27 such studies an attempt to learn whether the consumption in the exchange bears any relation to the amount of food consumed from the mess of the same organization. The canteen consumptions are arranged in the order of magnitude beginning with the largest on the left, and, for comparative purposes, the mess consumption is placed beside the canteen consumption. It will be noted that there is no definite relationship between the two. One cannot say, therefore, that soldiers purchase a large amount of food from the canteen because the mess does not supply a sufficiency of total energy. The average consumption for these 27 different canteens is 405 calories per man per day; the average for the total 261 studies is 365 calories per man per day. 544 JOHN R. MURLIN AND F. M. HILDEBRANDT abuvy>y-4 sq: wt Nop J vou sad purses Pov Ap @bou8y Sosse2 & Paerddog £/0E3 OU ay ae ipgss BO z- buDyor yo - paseyosncl /P> Ou ousnw — eco! sec) {SOD Aw » 1 jp> abousny - 50 > eee: sec!) 4 2 ose 3 , }P2> COO! 43d {SOD abDsanw ‘ SD waisne BACH US pee) ee Oo a Ree Pe oo SU. snaasa- te Ey ogay ntti CUS be ee ee ee Ce BOSe _"seD sounjpoquiyy, G—-- - AGOD ‘ wa don PIrts aber ey “Ia My 3 wos te yog) 2 a2 | AACS cloasy “bey Chart 5 r ‘ t t . ‘ cae xia \ = . Ses — = =| aca Peony a eh “£ § = ri) SSS aos Sic is eh a= °> =S- ae - “ 2 ripe ————————— xa -- el —buaros yoo ——_q-=— -- = \ aoe SSS SS id \ Eee Ss ON ea) Os Q y fc : N Oe < el . ~NBAZG 6 —~ @S3torc ~os == 8 1 \} © i Usisns " te Wm disc’ Ves eu es ° 0 ee shes wits =) “fun ize‘s o> ———_ -- it % a > + 1 D —— al wr rox oy"b ~ : ms : 2 o Pu © wy Cant vo F> ee: ——— hayuoser aser Ov aunvae ! —$*48 OW IPy*g es ___ = “ia ws i083 4°90 O73le DicnwH>D — tMeyprrob-O C4dW wqtattewL eC Oe repre sents number of colories “ S32 josuseeD ¥ DB awww F re: i Aneel J ———. tua sii * Hod 2} : oe UMS Lek Nee 33 = i res Je pees AB) oi o > g a) 8 cy v ra) 2 ; AVERAGE FOOD CONSUMPTION IN ARMY TRAINING CAMP 545 On chart 6 is shown a frequency curve representing the caloric consumption per man per day in all the exchanges studied, and a frequency curve representing the cost per thousand calories. The noteworthy feature of this study is that the frequency curve for the Go so M4 38 F » 40 ¥ y x f FREQUEN CY— CALORIES CONSUMED | ae 4N POST EXCHANGE u j G 20 d c t 16 e r so 100 180 200 250 300 350 400 4350 Soo Goo Joo B00 Joo 19° CALORIES PER MAM CER oA t Q 7 g <¥ tN <5 60 = wey” i ee mf meneet Gi ZN FREQUENCY -~ CosT PER sQ00 oO Consumption qr cost) Vs found CALORIES POS EXCHANGE Shee EE ae SANS vy r 3o U 40 2 ¢ ll 20 v 4 10 ° wm 1S Zo 2s 30 3S 4o AS 50 ss Go coer Pe R 100° CALORIES (CENTS) Chart 6 consumption is a skew curve, while the frequency curve of cost per thousand calories is symmetrical about the mean of all the observations. It is evident from the first curve that the amount of food purchased by the average soldier is not a mere matter of chance. To some extent the form of this curve is explained by the value in calories THE AMERICAN JOURNAL OF PHYSIOLOGY, VOL. 49, NO. 4 5A6 JOHN R. MURLIN AND F. M. HILDEBRANDT of the 5, 10, 15, 20 and 25 cent purchases; to some extent also prob- ably by the fact that in many exchanges restaurant sales were made, while in others what might be called confections only were sold. The average consumption in the canteen does not, however, rep- resent the average consumption outside the mess, for in many camps adjacent to cities, the soldiers had passes after the evening meal at the mess, and much supplementary nourishment was purchased in the eating houses in town. Several attempts were made by the nutritional survey parties to estimate the quantity of food consumed in this way. In some organizations men were required by order of the company commander to report what had been eaten outside the camp. In some instances there is every reason to believe that these reports were truthfully made but the terms in which they were reported, as, for example, “‘two pieces of candy,” ‘‘a piece of pie,”’ “‘ham and eggs,’’ etc., were too indefinite for computation. If a camp distant from any town is selected and a survey of all the camp exchanges is made, and the sales pro-rated for the entire camp population, a fairly accurate estimate of the food consumption outside the mess may be obtained. At Camp McClellan it was found possible to undertake just such a study. This camp is situated at a sufficient distance from Anniston, Alabama, to bring the consumption and purchase of food outside of camp to a low value. Also less out- side food was received at this camp at the time of study than in most of the other large camps. The study was made by Nutritional Survey Party No. 8 under the leadership of Captain H. A Mattill in March, 1918, several months before the departure of the 29th Division for overseas. The summary of this canteen survey shows that the expenditure per man per day at Camp McClellan during the week of the study was 21.9 cents, distributed as follows: Candy: 05: seat oe see 0.143 pound 6.17 cents 28 per cent Drinks: 5). 2 ance cee er Oe ebb 5.05 cents 23 per cent Cakes, cookies............ 0.214 pound 6.58 cents 30 per cent Bruit:00i02. «beeen 120) O08a pound 1.06.cents 5 per cent lee cream’. .°..Jaepeseck. oe O.0l2 gallon 2.00 cents 9 per cent Sandwiches, ete........... 0.044 pound 1.06 cents 5 per cent 21.92 cents 100 per cent — The following notes quoted from the report summarize the obser- vations of the party making the survey on the canteen situation at this camp. AVERAGE FOOD CONSUMPTION IN ARMY TRAINING CAMP 547 The soldier buys food at the exchange probably for three reasons: (1) as a pastime and for sociability; (2) to secure sweets that take the place of alcohol, in the case of those who have been accustomed to its use; (3) because the desire for sugar, physiological or habitual, is not met by the army ration. General observa- tion gives most weight to the last mentioned cause. For his candy the soldier pays at the rate of 44 cents a pound; for his pastry 31 cents per pound; for his ice cream at the rate of $1.60 per gallon; and for sugar in the various drinks over $3 per pound.. Of the total expenditure 30 per cent is for cakes and box crackers, 29 per cent is for candy, 22 per cent for soft drinks, and 9 per cent for ice cream, a total of 90 per cent for sugar and starch preparations, leaving 10 per cent for fruit and mis- cellaneous items. Using an average analysis for the various classes there is furnished (approxi- mately) by Calories ERE ie, a) im Reh a WESSEL. 3 MAINE YE, wccl disyeraig kennels are 4 aa 305 Pees! (COCR, COLA; CCA) ciets ac cdl. «obvi «ce oc daimal he's oe abelele eres 72 ee ey Pee a 18 Cake, 0.21 pounds.. Sey Weicte, Me SO Sea E Se oe: Cee a meee iogeaa (| ion eee 0.012: gallons Re EPS S eh atey ober Neste eee OOS LOL Miscellaneous ‘eandwieh), 0.044 pounds. Be Neem sc percietene iver LOM: A total of.. 5 ae Meee, oe ars ares Oe eRe a fe, Si Saeed eee ale, oid bt OOS at a cost of 33 cents per 1000, which is about three times as great as the cost of 2 similar amount of food in the army ration. The average net consumption in the four messes surveyed at Camp McClellan in the early part of March, 1918, was 3827 calories per man per day. Adding to this the 633 calories which represent the average consumption from all the canteens, gives the surprisingly high total of 4460 calories. The average total consumption in the camps is found by adding to the average for all messes studied (427) the average for all canteens (261). Thus 3633 plus 365 equals 3998; the result in round numbers is 4000 calories per capita per day. Lusk* has estimated that it requires 4100 calories in order to maintain body weight and to supply the necessary energy for a seasoned soldier weighing 70 kilograms (154 pounds) to do a forced march of 30 miles in 10 hours carrying a pack weighing 44 pounds. Of these 1767 calories are for basal metabolism, that is, the mere maintenance of the body temperature at muscular rest. Standing alone requires 118 calories, walking 30 miles in 10 hours without pack requires 1705 calories, with pack 484 calories additional, making a total of 4704 calories for maintenance metabolism and the muscular effort. 3 From an unpublished lecture on the Dynamics of Nutrition, written for the Division of Food and Nutrition as a part of the training of nutrition officers. 548 JOHN R. MURLIN AND F. M. HILDEBRANDT We have already seen that the average weight of the soldier of the first draft after four or five months’ training in the camp is 146 pounds. For this weight the theoretical metabolism according to Lusk is as follows: Basal metabolism 1695, standing 113, walking 30 miles in 10 hours 1606, carrying equipment 44 pounds 484, total 3898. It may be seen therefore that the average soldier receiving 4000 calories FRE QUENCY WEIGKNT STOOY OF INCREASE Im WEIGHT OF S25 MEN IN THE 303 FA, CAMP DEVENS The weights were divided mto groups differing by 5 pounds, and the number of individuals in eact) group counted. The Grove Ydiween 110-5 includes individuals weighing om Wi TO .t5,1Inclusive, The qroup befween 5S and 120, indivicuals weighing from 16 te 120, inclusive,etc. Im the above Qrapi, The absassas give the weiqhts, The ordinates, the number ef individuals 12 each welqht qroup. The sold line shows Me distribution at the Time of enlistment, the dotted \me, tne distribution S months tater. Averages are shown im a similar manner Chart 7 daily has energy supplied in sufficient quantity to do this maximum amount of work every 24 hours. If the work is not done, it is obvious that the soldier will take on weight and the universal testimony through- out the camps is that the recruit has gained anywhere from 3 to 9 pounds in the course of four or five months’ training. At Camp Devens 523 men of the 303 Field Artillery made an average gain, which was nearly uniform for men of all sizes, of 6.6 pounds (chart 7). AVERAGE FOOD CONSUMPTION IN ARMY TRAINING CAMP 549 It is certain, therefore, that the average food consumption of 4000 calories is sufficient for the training period. Making an average allowance of 7 per cent for waste (see table 1), a total food supply of 4280 calories would amply supply all needs, including the canteen. This, it should be remembered, covers the needs for men of all sizes and under all conditions of muscular work and climate. VERY MEAVY LABOR |} q HEAVY [LABOR | STONE s s DRESSMAKERS Chart 8 FOOD CONSUMPTION IN THE ARMY COMPARED WITH OTHER OCCUPATIONS In chart 8 is shown diagrammatically the relation of average food consumption in a training camp in comparison with lumbermen, stone masons, farmers, machinists, professional men, tailors and dressmakers. 550 JOHN R. MURLIN AND F. M. HILDEBRANDT This diagram is based upon statistical observations made by well- known authorities and summarized in Lusk’s Science of Nutrition (Second Edition, p. 348).. The physical work of the soldier may be characterized as somewhat heavier than that of the American farmer, and not quite so heavy as that of a stone mason, who works steadily at lifting and hammering his materials for a period of eight hours. DISTRIBUTION OF NUTRIENTS IN THE ARMY DIET By reference to table 1, it may be seen that the average distri- bution of calories derived from protein, fat and carbohydrate consumed in the mess is 14 per cent, 31 per cent and 55 per cent respectively. ’ The distribution for the different number of messes averaged in that table is seen to vary but little from this standard. Chart 9 shows the range of distribution of calories to the several organic constituents of the diet. The percentage of protein calories varies from 11 to 17, fat calories from 20 to 40 and carbohydrate calories from 45 to 65 calories. Throughout these ranges the dis- tributions are fairly symmetrical about the means. If they were perfectly symmetrical, the means would obviously coincide with the averages. Stated somewhat differently, it is obvious from the study of this chart that any given recruit cast into a camp and passing through the mill mechanically, as a ball on a roulette board, would stand an exactly equal chance of obtaining a diet which would contain 25 per cent of fat calories as one containing 37 per cent, that is, an equal distance from the mean. Similarly with reference to carbohydrate, he would stand an exactly equal chance of obtaining a diet containing 50 per cent as one containing 60 per cent of carbohydrate calories. So also with the protein. When the canteen consumption is taken into account, the distri- bution is slightly changed. Examination of the report from Camp McClellan already referred to shows that the average canteen pur- chases contain 8 per cent protein, 16 per cent fat and 76 per cent carbohydrate. When the 365 calories are distributed according to these percentages and added to the consumption obtained in the mess, it is found that the distribution of protein, fat and carbohydrate for the total consumption is 13 per cent, 31 per cent and 56 per cent re- spectively. The predominance of carbohydrate in the canteen con- sumption serves to lower slightly the percentage of protein, to raise slightly the percentage of carbohydrate and to leave unaffected the percentage of fat. 551 AVERAGE FOOD CONSUMPTION IN ARMY TRAINING CAMP °o 6 RYO si ol WAAAY ayeuphuocucsy ZB 4o4 (3 ‘abyjyered roripur SPSSIOSNO “sassow fo sdcqunn AORMPUV SIBOUIPUQ ‘saccow r1zy UL Prauinsuer poof ut aouphyoqsor puo 404 SUNzoud fo abeyuessay Have WOLERIaISILS(a S26sa2 fo -own —— ren §52 JOHN R. MURLIN AND F. M. HILDEBRANDT COMPARISON WITH OTHER DIETARIES It is a matter of interest to compare this distribution of nutrients in the army diet with the distribution in certain standard diets well known in the literature of the science of nutrition. It is somewhat surprising to find that the percentage of protein is considerably lower in the diet of the soldier than in that of Voit’s old ration for hard labor which has always been regarded as a moderate one from the stand- point of protein. The impression that the consumption of meat in the army training camp is excessively high is not borne out by this comparison. Protein is lower even than in the diet of the Finnish peasant as reported by Sundstrém in 1908 and in that of the Amer- ican farmer at hard labor as estimated by Atwater some twenty years ago. The total energy consumption of the American soldier in training approaches the Atwater standard for the American farmer at hard labor. TABLE 3 Comparison of the soldier’s diet in United States army training camps with other standard diets for hard muscular work GRAMS ‘ CALORIES Percentages protetil!’ Rat i) teen | apokad rotein a Nf ota Carbo- drates Protein} Fat ead drates Sundstrém (Finnish peasant)....} 136 83 | 523 | 3474 | 16.1 | 22.2 | 61.7 Voit (hard labor)...............3| .145.| 100 | 500) /"3574 | 16.6 | 26.0))jo7=4 United States soldier (hard training); ....2c6.0.-..020..0..| « 129) 4136) 545°] 3998 | 13 2a SiG ees Atwater (farmer, hard labor)....| 150 125 | 580 | 4150 | 14.8 | 28.0 | 57.2 Likewise in comparison with the rations prescribed for the training period of the other allied armies, as may be seen from the following table, the percentage of protein in the United States Army is lower than that of the British, Canadian, French or Italian Armies. The percentage of fat consumed is lower than the amount prescribed for the British and Canadian Armies and higher than that of the French and Italian Armies. . The total energy consumption, however, shows how difficult it would be for the American soldier to live on the training ration of either of the other armies. AVERAGE FOOD CONSUMPTION IN ARMY TRAINING CAMP 553 PERCENTAGE OF CALORIES SUPPLIED BY CHIEF COMPONENTS OF THE RATION In chart 10 is shown the percentage of total calories supplied by each of the more important constituents of the army diet; likewise the percentage of protein calories, fat calories and carbohydrate calories furnished by each of the more important constituents. This study is based upon the first 87 messes and the first 213 messes surveyed. The importance of bread, beef, potatoes and sugar stands out prominently in a comparison of this sort. The chief difference observed between the TABLE 4 Training rations of the different allied armies GRAMS CALORIES Percentages Z a Carbos Sug | Sy SS rotein at y- ota drates : Carbo- Protein| Fat dy- drates British Home ration, May, 1918..| 124 | 136 | 419 | 3483 | 14.6 | 36.4 | 49.0 Canadian, July,'1918.:........... 107 | 118 | 344 | 2946 | 14.9 | 37.2 | 47.9 French, Normal, March 29, 1918 | 138 98 | 467 | 3604 | 15.7 | 25.3 | 59.0 Italian territorial, February 1, LESAUF? 5 oe Re ae 127 38 | 469 | 2797 | 18.6 | 12.6 | 68.8 United States Garrison ration A. Ri 121 “| 147 \ 174) 648 |-4859 | 12,5 | 3320: 154.2 Consumed in United States training camps 427 messes and canteen purchases.............| 129 | 136 | 545 | 3998 | 13.0 | 31.0 | 56.0 two studies lies in the fact that there is in the second a considerable increase in the percentage of total energy as well as the percentage of each of the three nutrients derived from foods other than the principal staples included on the food list. In other words, from the time when the average for 87 messes was compiled to the time when the average for 213 messes was compiled, a period of two or three months, the number of different articles of food used in significant amount in- creased considerably. This reflects greater freedom and more in- telligence on the part of the mess sergeant in purchasing food from outside sources. R. MURLIN AND F. M. HILDEBRANDT JOHN O00 OL WeYD eb: ‘57 Avorsgay puo Libis 42940 UremMted pokeAuns gam sassow LO By F ‘sesso gz yy fo rg uw Ueyduasucd 2bheienre ey Wo arti] tie ‘Sassou Ber ener AK {4o;0> PRYOQ4es /21ay puo *sai4ojo>3 s e249 so Seavdxe 242 puo s, “y ; poe Seiden 40h ‘Urappsd ‘hbsowe joy fo yunoun moys sasob;4 ‘Sejp4pKhyoqios pup ‘sy fe ser4r0s so spoof peso Kywonbauf yeoww ay fo NOILNG cSIQ SJIYOW)D spoof eyo (687) G9 pPeuuvs'soes ch: o , PauuTs‘urj hs = Kup ‘saqyooay (L5'/) 04° Sa $2amMS 'Saojq0) (981)06" wa 1uo4n 2, ($97) 06" ad Peesodona'H/iLy (LIW)IO1 wa Kurwoy 7e)ez 1 Cm seury (IK) OS) cmd JP auwo (ob))o0 wm spoof 180fyoo41g (zi) 251 wm WOr (£61) 99) md Pau (96')06'1 mm 1/228 WU405 (621) 56) eked Ang (162) Se 2 mmm Pep ‘suoag (92 '¢) 2 ———_ “00/4 (8b 9)9F . emi—~___ QM'S Pojojoy (206) 226 Camm 4f oc ‘possg sobng (ep 12) zB ——_— (96 1E) SL bz a JonpiAlpul SAO WWD aLVYCAHOGY VD spoof 1210 (16%) Co 2/ ——n_—smmmmmmammmmd P2/-P's01j;20a) Ors fPome ‘sdaqo, tz * peuuorUuson se © Ruimoy Oo @ Hiesa20l (o1r/oo a PeiLer'soay 19’ = Yysaaf ysis (Ce1) SO ed Dawe Kaginag te spoof jeofyouig se = Je 2uwu 40216 0204 (641) 56 Sod [2M (£807) 96 Sad 4dAIy (967) 00/7 ad @S2249(/01) 20; wl Povuuwr'forg (0L1)80/ Som prersasosd ‘Yyely (261) 8/7 — [224420 (280 BS) amd mo (oe 220s — cbbz(/ TOL 7 med YSasf 746d (OP) OST mmm Pe240AS OAD 'Hj1i-v (FLL) 66S meal eboenos (09/085 —— C2 (OE) 99 eed 400;4 (LLG) OS & Smad hip'sueag(sit)L9 ° =! () v feos ‘peosg (70 23) 307.) SS YSa4f -f20Q (/91E) 096 E mm RG SAa!yO rv) Ni Loud Was jail eeunsodiuy Dayojes beimoyco wo fiz Us uoendusnsuca @beuanno oy wart Ppeulluuaiap SD ® ojuess9c 2oe fo arpa 3y UW wasadoy 4299 pies My pue s4nbif scarf wy, “Kyariyredso4 /242% (S2140/2> Urgosd ojos 'So140;e> jo Dp Kyoqund pun Spoof 4340 (QU Z)LS 0 ———as +2ams ‘ed0;mo04 OMe peuuns'tusoy gite 4rAI7T Ore Yyrouf‘ysra bre peauiuaorbi es SUL Taal "S204QJo/ prs P2rarscasd *ysi4(zs)70°S DIA (99:)72S Pauuor ‘F229 (z9)eo@ pesp'suveg bce APe1s OF @ 12241120 (99':)79 @ , Katee 99n ic = 2920949 (2h) Cf! Sa O87 - Des 0bu0K103/0 gue 8bbhsz (6S) 06) mm PAOCTE SS mmm 40S “por4G(z206)b6e7 —— P2498 ON Hiro OLS mmm pbocnos (90:5) >.> ad ysoss ‘yveg (0b'2) 80> mmm WweoHy (OOS) 95> am ©0202 SOL EEE 4WwEe 69809 ———— weapsd ‘Kbsavo Salyo wd Lv spoof 42410 (S97) 106) qummmtemmmmmmmmmmmmemmemmalcccd p10y ‘poe.g (55750 % YSeaf *yB8ig gre Pyerodona' wii (gz2-z)1z Sa 4BAI7 1z°8 128A pz pauues ‘faag szs Per4asaid ‘*ye14 az Kagjoog (ze)es @ POUWWo> *s004 og & Petiuws *u4o> (ZS) 1b P 2p *Ss2ys0Ry (pb) tb ' 420n'S *Sa0fQ10, (6L) ES ats; sobs pus0yo 2S JU040IOLy (601) 65 al BF2045 (29) 65 be PAST Oh mm Seung (2Z3)S1' Kurwoy (79) ec & 5663 (20) hb a spoof jsofyoa.g (607) 46 Sa Sal Hi©Gm\ > Uo (L071) Sot wa omy (RIOT) wom WLOL jae en esa = JOBWU40D (64°) SZ hed daag (eo) oct om YSO4f <4 40% (18°) 897 md tewoH (16/) TL! cme Dhosneg (€/ 2) tL) 4OD0g (ri) at 40499 (862) 612 suceeg Us rysst (s9°S/p207 U8o) 5oo ——— 4090/4 (OV) LEE elem ym ‘Seopmjog (GS) LS —d 2061s (1) OO ———— YOM A POD ED LT PEE PDQ (ODO ———————————————— 555 AVERAGE FOOD CONSUMPTION IN ARMY TRAINING CAMP IT WeqO ‘6 Gt Aequunu Stuy gnu 722M 30 gut butaeyue S3\>)p40 ie saquau sug umoys £1 O,4V "(fo UMOUS) ZL jooysunypaly “Sassou es2aiffo yy woof ooa- FT *(,@,J2 uMoYus) O'S! S! clnoub SIL So UpduU JOROUIYI4O SUL “BH IL Kop-¢ 0 uo Suc zrunbso Ul s2ssow I wou Yy9d-F “(ve 4 MOUS) BZE S! dawb sis jo uveur pOd yoatubypso auL SmrospG Ut sosscoul o6e fo SkoAUNG W22M-BVO wait ood - S&S dSWIHDAwH-SSOUD AO NOI twHiwidaxKsa yaanm SNo Yost RUMOANDAWNI WO le So Vm A ae Vd JH ywasa2aia sao waqgnaw SG 66 (SG. OF isu DCL CON OGIa View Oven SG 10S) Set uae “ SS G x r coo 1 “11) 1 oz | ) ay 53) ee *pouins.so «=SlWalt poo} H) fo sacpuums usaib fun YUdi4m 1 Qorp4o “mMeemM BUO H snucdw biricodiuo> S2USsiP SUL OL. pa.iajve sway1 poof aauel ie fuow MoU SAAOUS nssivsqy ‘wasM SNO HOS ScwmolwznNyOUo DHiaasSs wil aQasn Sai1sav ao Vwagagwnwyw SS SS eee eee HAvyuD KON SIND Ass Ly SaSSaLU fo 22149 SAMAOUS | os = 596 JOHN R. MURLIN AND F. M. HILDEBRANDT VARIETY One of the most important factors in the diet for the maintenance of morale is variety. In studying this question one is met at the out- set by the difficulty of assigning a value to such a factor in the mess. The most obvious way in which to measure variety is to count the number of different articles of food on the inventory for a given period and consider this an approximate measure of this particular dietary factor. Chart 11 represents graphically the results of a study of this sort made on 390 army messes. In making the estimate of ar- ticles on the inventory everything purchased by the mess sergeant for preparation of food for the week of the survey was counted. This included spices, tea, coffee, etc. The average number of articles used per mess per week was about 55. For organizations on the march, where difficulties of preparation and transportation of food necessarily demanded a simpler menu, the number of articles used per mess for a three-day period was 15.9. For an average family* 39 different articles enter into the weekly food inventory. At first glance, therefore, one would say that there was less monotony in army diet than in the diet of the average household. However, it is not entirely certain that the count of household articles was made on exactly the same basis as the army count. All that may safely be said is that army feeding, so far at least as variety is concerned, com- pares very favorably with household feeding. ‘ From dietary studies made by the Bureau of Markets of the United States Department of Agriculture in the autumn of 1917. : VARIATIONS IN STRENGTH AND IN THE CONSUMPTION OF FOOD BY RECRUITS AND SEASONED TROOPS PAUL E. HOWE, C. C. MASON anp SANFORD C. DINSMORE From the Section of Food and Nutrition, Division of Sanitation, Medical Department, United States Army Received for publication June 3, 1919 Nutritional Survey Party no. 2! of the Division of Food and Nu- trition was asked to take up the question of the use of the Martin (1) strength test as a practical means of classifying and assigning men for particular duties in the army and as a means of studying problems relating to food consumption. Preliminary tests were made at Camp Fremont, California with the aid of Dr. E. G. Martin. At our next station, Camp Lewis, Washington, the tests and surveys detailed in this paper were carried out to determine whether or not there is a relation between the food consumption and variation in strength of recruits. Due to certain difficulties, the original object of the work was not attained. The results are, however, of considerable value with regard to a, the variation in strength and weight of recruits during the first weeks in camp, and b, the variation in food consumption of the same group of men from week to week in the course of three and four weeks and of different groups of men at the same time and under almost identical conditions. Such data are of use in connection with the evaluation of studies of groups of people.” Determinations were made of the variations in strength and of weight of approximately forty men from each of eight companies of recruits; Company 6 of the Depot Brigade was quarantined during part of the time and the results are not included in the strength tests. The studies extended for three consecutive weeks; a smaller number of men were continued for the fourth week. Weights and strength were determined 1 Capt. Paul E. Howe, Lieut. C. C. Mason, Lieut. S. C. Dinsmore and Lieut. B. H. Harrison. 2 The question of the number or length of studies of this nature which must be made to obtain a correct estimate of the average food consumption has been treated by Lt. Col. J. R. Murlin (2). 507 558 P. E. HOWE, C. C. MASON AND S. C. DINSMORE at seven-day intervals. The food consumption of the messes from which the men were selected for strength tests was determined in weekly periods. The men were inoculated and vaccinated during the first two weeks of study. The recruits arrived at the camp between April 25 and April 28, 1918. They passed through the usual routine of physical examination, and were inoculated with vaccine against typhoid and small pox. The men lived in barracks and received their preliminary training during the time of observation. During the first two weeks they were in quarantine. The character of the work varied from day to day but was nearly uniform for all companies on the same day. No work was done on the day following inoculation. The mean temperature was practically constant throughout the work. Two of the most in- fluential factors affecting the quantity and quality of food consumed in an army mess, the menu prepared by the mess sergeant and the character of the cooking, were at least in part minimized through the use of the same menu for each of two groups of four companies and by the presence of trained cooks belonging to the School for Bakers and Cooks, who were permanent members of the Depot Brigade. The cooks were under the constant supervision of a sergeant cook- instructor detailed to us to supervise the cooking. We feel therefore that the factors affecting food consumption aside from the inclination of the men to eat what was put before them were eliminated as much as can be expected. The men of Companies I, K, L and M of the 364th Infantry repre- sented seasoned troops; they had been in the organization since October 1917 and this work was conducted in April and May, 1918. These men had received the maximum of training given in this country. All the companies were in the same battalion and did practically the same work. No attempt was made to control the menus in these organizations since all were well established. Strength tests. Data with regard to the strength tests are given in tables 1, 2 and 3, pages, 559, 560 and 561. Ten tests were made on each man (right and left pectorals, right and left wrist flexors, right and left forearm flexors, right and left thigh abductors, and right and left thigh adductors). The results according to Martin represented 17.7 per cent of a man’s strength. The choice of the men was made directly from the rolls without knowledge of individual sizes or weights. Men with venereal diseases were excluded. The following facts will be found from an examination of the data: MUSCULAR STRENGTH AND FOOD CONSUMPTION IN ARMY 559 TABLE 1 Average variations in strength of individual companies, expressed as pounds pulled per man, and in weight, 166th Depot Brigade STRENGTH VACCINA- NUMBER | TION DAYS PERIOD WEIGHT : Thigh TOTAL Sea ss jee ‘ Pectoral Petes F Recacas aed uetors Company 5 pounds 1 35 3 156 135 61 97 67 844 2 35 3 156 125 42 91 59 750 3 35 3 158 125 57 95 59 797 Company 7 1 34 6 158 118 36 90 52 694 2 34 6 151 115 42 95 55 724 3 34 6 157 133 47 96 54 790 Company 8 1 33 5 158 126 49 95 65 824 2 33 5 157 111 42 86 56 723 3 33 5 157 114 50 92 268 773 Company 9 1 34 6 150 114 38 85 55 695 2 34 6 149 110 42 86 53 689 3 34 6 151 118 45 91 57 734 Company 10 1 35 5 151 118 42 88 57 726 2 35 5 152 115 42 87 54 702 3 35 5 153 125 46 93 62 775 Company 11 1 35 £ 151 121 52 94 56 798 2 35 4 151 114 42 85 53 690 3 Bis) 4 151 109 42 86 49 668 560 P. E. HOWE, C. C. MASON AND S. C. DINSMORE TABLE 1—Continued STRENGTH VACCINA- PERIOD NGM eon BI GHD | : Thich TOTAL Vitae weer Pectoral | guna’, | Hgacarm | abductors Company 12 pounds | 1 26 2 154 120 62 92 54 761 2 26 2 154 116 42 83 55 698 3 26 | 2 156 110 55 85 51 700 Company K 364th Infantry 1 24 — 152 132 64 94 52 789 2 24 — 152 123 57 85 49 724 3 24 — 153 121 57 92 47 726 Note: Average values for muscle groups represent pull for a single group of muscles, e.g., right pectoral, left thigh abductor. TABLE 2 Average values for total strength as pounds pulled per man for men tested on four successive periods STRENGTH WEIGHT ORGANIZATION Sean 1 2 3 4 1 2 3 4 Companyeoe eee ce ee oe eal oe 846) 762) 802) 800) 156) 156) 156) 157 Cammany Wass are a 14 711! 730} 793} 738) 157) 154) 156} 157 @iammany Bi. ob es Pega ace ee alee 810! 706) 753} 804) 152) 152) 151) 152 WMEPANY: 95, 6c/st.d 10. Sc. aera mG 684! 670) 720) 705) 147) 147| 149) 155 Comparnyal0: 7). et asace teeters 13 701) 678) 752) 732) 145) 145] 146) 147 Company Ul oe. aise a sae 9 709) 635} 632} 701} 151} 150} 152} 152 Companyat2 . Sysss cscs Coe nel mee 770| 704} 708} 760) 154) 154! 156) 157 Company K, 364th Infantry......| 24 789) 724| 726 152} 152) 153 Values for strength represent the sum of the actual weights pulled or 17.7 per cent of total strength according to Martin. a. Every company, except Company 10, showed an initial loss in weight averaging 1 pound. By the end of the third week there was an average gain of one pound over the original weight.’ ’ Similar losses and gains, but of greater magnitude, were observed by Lieut. W. A. Perlzweig in his studies of recruits. MUSCULAR STRENGTH AND FOOD CONSUMPTION IN ARMY 561 TABLE 3 Average results obtained from all strength tests on the 166th Depot Brigade, expressed as pounds pulled per man STRENGTH NUMBER OF PERIOD WEIGHT N 2 Thi h TOTAL — Pectoral | gurons | Tgosers® | abductors A. All men a 232 153 122 48 92 57 760 2 232 152 115 42 88 55 708 3 _ 232 154 119 48 91 57 746 B. Men tested four times b. Data with regard to strength show an initial loss with recovery practically completed by the third week and then strength held during the fourth week. The men were at low ebb physically at about the end of the second week. The second injection had been given, they were not fully accustomed to the new life, they were all tired from the unusual drill and most of them were more or less homesick. We noted in making the tests that the second one aroused little interest. By the time of the third test most of the men had returned nearly to normal and their mental attitude had improved. The results are reflected in the strength tests. The data obtained from a smaller number of men in the fourth week bear out the fact that recovery was practically complete by the third week. An analysis of the percentage losses and gains in strength of the various muscle groups tested with relation to the total weight pulled on the first test shows the following average results: PERIOD PECTORALS WRIST FLEXORS FOREARM FLEXORS HANG Honea PAU ee ADDUCTORS 2 —0.6 —0.8 —0.5 —0.4 3 +0.4 +0.8 +0.5 +0.3 THE AMERICAN JOURNAL OF PHYSIOLOGY, VOL. 49, NO. 4 TABLE 4 Average food consumption per man per day during three successive weeks, 166th Depot Brigade CARBOHY- PROTEINS FAT DRATES CALORIES Company 5; £/30-5/ 6/18... 2. 2... eee 126 124 546 3912 A OVS [Lecce tata Taco oe 110 121 457 3448 RIA OW DO [LB ice soc omens ee ae < oe 126 121 543 3863 UNOPS ES, CS la ae RE RE eee ae Pd 121 122 515 3741 Company.'6,-4 30-5 ['G/18) i. 2. eee see ete 104 bby? 421 3241 sth ho (LS: dase o> ie oS ee a) 127 466 3538 LAD QO Siar a. nee eee 102 113 407 3145 AWEYA Pel oacuc poche oe qlee themes eee AOD 119 431 3308 Company 7274./30-5 /°6/18.....g A so ese: = 89 111 375 2931 Biot =5 [UBINS oo ccuters- wr cere 100 130 349 3046 By 14-5 (QO fAS = 2 cower: ook beep 127 152 423 3669 AVETARO! (etna fess toss: « eek eee paOe 131 382 3215 Company 8, 4/30-5/ 6/18.............2......{ 155 172 495 | 4264 BT TMS. ee a meee 91 335 | 2557 5 /14-GHOO /1Secd) ve eel me et 133 598 | 4244 ikverdperd. Lignertecwlt be sluex eid «dae hatde lapel Company 9°47/80-5 76/18. 2)... = eae) OU 82 420 | 2852 Say clay key Fo phe were Veen AA a) 116 482 | 3505 BAA SIONS AI Wee RE, Te 147 141 533 | 4096 Diveraeors c.- tayo bane ce peek: 31h te amet |e a Company 10, 4/30-5/ GAS ee ee 85 75 517 3162 Sif TADS 1B es SE ees. e 119 121 395 3231 6 (14-5120, [18-2522 ext ee atebe 115 112 525 3661 AVEVARC! Fs cio osese ec edive Ne seineeine ciepeell” | skis 103 479 3351 Company 119.4)/3025 61S eee POS 72 465 3022 5 TNA eine ne a1 93 538 | 3542 5 14-5 20UES a eee 97 "| = 92 397 | 2879 AVerage.. sss eee Se eee 107 86 467 3148 Company 12, 4/30-5/ 6/18...................| 129 108 627 | 4105 ; 5 7ST IS ea ee. eG 103 421 | 3119 5/tL5 OVI ee ats 106 518 | 3591 Averaged! 352. 0..24-ciisetee ae coer oe eens aa: 118 106 522, 3605 Average. of all, ; (0.452055 3. ode 112 114 469 3483 562 MUSCULAR STRENGTH AND FOOD CONSUMPTION IN ARMY 563 The percentage losses in the second week are practically made up in the third week. The wrists show the greatest loss; the men had just received their rifles at this time and this may be a factor. There does not appear to be a direct relation between loss in strength and the proximity to the time of inoculation. TABLE 5 Average food consumption per man per day during four successive weeks, 364th Infantry, seasoned troops CARBOHY- PROTEINS FAT DRATES CALORIES arpa yes (23-4 (29 [18 05 hd. 8. eee ec 133 150 555 4212 By BO = AG. [USk ds ceevescs ey airetoceyores oie c--s 139 153 522 4127 oho SHAS BOE aufe.5 oo ae, bes ecs 125 iG 604 4074 yy TA QOWTS). PRIME oc coz os na: 113 98 526 3527 ree ete He bal ERTS os mets i ah, lS 130 552 3985 Company. Kk; 4 /23-4 [29 18.4; 042.0... cece ee 100 102 535 3548 A [SOHO EG NSAP AEs he ses seit 142 151 485 3972 HT e=0) OWA e ae. AL aes SERS ene 112 119 603 4034 By TAS ZO 1S As ede ones 132 106 543 3752 Js S/ETDTRE 1 SO OCagS 8 B BIRO C. 6 I ene en ae 123 120 542 3827 Company L, 4 /23-4 /29/18.................... 125 142 ~ 475 3778 ASOLO MG LST REL cc oan Sosa ne 156 136 560 4200 Bi aeeor Si LS AY. GE eet sk 127 120 483 |. 3616 ey A= AZO 1S Ay Re eo oe, eke 116 117 429 3322 LAHTI ES CS RG ES SO. chS ERM Fano See 131 124 487 3729 Company M, 4 /23=4/29 /18..2................ 149 133 510 3936 A SO=O/EO [TS as 4a cris: . «occa cee ile! 109 427 3230 OY Ho EWES es aa es 123 124. 448 3497 OAR Oy ZO MSA eEEs, cue. artic tre eres 116 110 459 3385 JSTOR GS, de RPG BEE Cte BIO Ee 125 119 461 3512 Rupa RDRIUREC IPMN 1528.0. Sa ls tack és cc acs wisns 126 124 510 3764 The results on Company K, 364th Infantry, are not of value for — comparison with the Depot Brigade for the training schedule prevented our getting the men in approximately the same condition for the dif- ferent tests. In the second and third tests the men were fatigued as the result of active and heavy work. The values obtained indicate the effect of fatigue. 564 P. E. HOWE, C. C. MASON AND S. C. DINSMORE TABLE 6 Average food consumption of different companies using the same menu at the same time. 166th Depot Brigade CARBO- DATE PROTEINS FAT SYDRATES (PE SSUBESS A}30-5) 7 187 Company $2 0222... «eek 126.0 | 124.0 | 546.0 | 3912 Company 6...0...0..........| 104.0) D170) “421200) eee Company 72.50.60 ..<.0%-1) 8920 | 91104 VS7a Os ease Company :8).....2- 4-55-08 155.0 | 172.0 | 495.0 | 4264 AVerage....:..0.02...2-.-| 118.5] 131.0)|. 457-5 1) ee Company 95) 3 cotscen. Cece 9020 82.0 | 420.0 | 2852 Company 103... :t05..f-30.46 85.0 75.0 | 517.0 | 3162 Company 403.0% eer 108.0 72.0 | 465.0 | 3022 Company 325... terciceek iste 129.0 | 108.0] 627.0} 4105 AV ETAL Cees os teiche ee toro | MLO SAO 84.0 | .507.0 | 3285 5/ 7-5 /13/18 | Company 5................| 110.0 | 121.0 | 457.0°) 3448 Company 625... 24. eceese 110.0 | 127.0} 466.0 | 3538 Company 71). ...0..20.....+| 100/01! 13005) 349,00) Sees Company. S24... |) Company, 555.5 ae 126.0 | 121.0] 543.0 | 3863 Company 6: .. ....-.2.....| 102.04) 213,04) 407-00) Ries Company Wie... ci cece cece: 127.0 | 152.0 | 423.0 | 3669 Company 8................| 134.0 | 183.0 | 598.0 | 4244 Average: ...65...5.00.60.|) 122.0) 129.7 |. A927 aware Company 9...........¢..2..| 147.0-| 141.0 |) 533. 0R "ange Company 10:.. 2... 6. ..2re} 11520: | 112200 "525700 aoa Company Je. 4.40. aye te 97.0 | 92.0 397.0 | 2879 Company A226. sich nev eer 118.0 | 106.0} 518.0 | 3591 AVETAGC 2. chi. 0 hy sic dont) 920% | ID: 7a)! 49S OSesood Average of all studies.....| 112.2 | 114.0 | 469.0 | 3483 MUSCULAR STRENGTH AND FOOD CONSUMPTION IN ARMY 565 Food consumption. The data relating to the food consumption are included in tables 4, 5, 6 and 7, pages 562, 563, 564 and 565. Tables 4 and 5 give the data from the same companies in each of successive periods. Tables 6 gives the results obtained for the same groups of companies when using the same menu. Table 7 gives the average values for each company during the periods studied. TABLE 7 Company average food consumption per man per day for 3 one-week periods, 166th Depot Brigade, and 4 one-week periods, 364th Infantry CARBO- HYDRATES| CALORIES PROTEINS FAT 166th Depot Brigade. 3 one-week periods, 24 studies \Canijopiny 355 sesdocts COC ODEO EOS nEnnSenroe 121 122 515 3741 CULE?) etl See On ee 105 119 431 3308 LE 200A peo A eee ee 105 131 382 3215 OD LEIS? 2 Ee 124 132 476 3688 SU SLSU/Ee INOS So tatiana ete a 116 113 478 3484 PMMNRETMANOIERES Nec a ctec sss cee cs cess) “LOG 103 479 3351 SPREE RED Lrie Pre. Sikes ids ods 6 alelslae wees ose 107 86 467 3148 TTL LE Le ee 118 106 522 3605 Average Depot Brigade. ......5........3-. tt, 114 469 3483 364th Infantry. 4 one-week periods, 16 studies MEAGRE teen eins sts cose sce --c-s| Lae 130 552 3985 WoT DUDE odo nt Soe eee 123 120 542 3827 (Carnytmityy IES Sabine Gado UCU Cee eae ei 131 124 487 3729 EID 01 ORS Se Be 125 119 461 3512 Average, Infantry Companies............. 126 124 510 3764 Grand average, 40 studies. ................ 118 118 485 3573 In considering the data it is to be remembered that each weekly average represents the average of the food consumed by approximately 220 men or equivalent to 1540 men for one day. The results are particularly interesting in that they give some indication of the variable food consumption which may exist under the very similar conditions. Even when using essentially the same kinds of food in the form of similar dishes there is a variation in the food consumption of different groups of men. 566 P. E. HOWE, C. C. MASON AND §S. C. DINSMORE That the results are characteristic of recruits is not borne out by the results obtained in the 364th Infantry, for here we find just as great variations as with the recruits. The average food consumption is somewhat higher, a fact which is substantiated by other data obtained by the Division of Food and Nutrition. BIBLIOGRAPHY (1) Martin: Proc. Amer. Physiol. Soc., This Journal, 1918, xlv, 538. MarTIN AND Lovett: Journ. Amer. Med. Assoc., 1915, Ixv, 1512. (2) Murun: This Journal, 1919, xlix, 531. NOTE ON THE ACID-BASE BALANCE OF ARMY RATIONS N. R. BLATHERWICK From the Section of Food and Nutrition, Division of Sanitation, Medical Department, United States Army Received for publication June 3, 1919 Interest in the acid-base balance of dietaries has increased greatly. in recent years. Sherman and his collaborators gave us the basis for work along this line when they made more accurate determinations than had hitherto been available of the ash constituents of the common foods. It will be recalled that meats and cereals show a predominance of acid-forming elements, while on the other hand fruits and vegetables have an excess of base-forming elements. Working under the direction of Professor Mendel, (1) it was my privilege to demonstrate the specific influence of the ash of foods upon the composition of the urine. This study showed that acid-forming foods lead to the formation of more acid urines and base-forming foods cause the excretion of less acid or alkaline urines. Certain exceptions were found, namely, plums, prunes and cranberries, which although yielding a basic ash, neverthe- less increase the acid excretion due to the presence of benzoic acid, excreted as hippuric acid. Although the question, whether or not an acid-forming diet eaten for some period of time is productive of undesirable results is debatable, probably the consensus of opinion is in favor of diets in which the acid-forming and base-forming elements are approximately balanced. Accepting this, it then becomes a matter of importance to determine whether soldiers’ rations are well balanced in this sense. Our soldiers in the training camps are subsisted on what is known as the garrison ration, the chief components of which are fresh beef, flour and potatoes. This ration, when completely eaten, is abundant in protein and energy content and shows an excess of acid-forming elements corresponding to about 44 cc. N/1 solution per day. Owing to the ration savings privilege, the mess sergeant is able to decrease the amounts of the various components consumed and receives credit for the same from the supply officer. With the money thus obtained, 567 568 N. R. BLATHERWICK TABLE 1 Acid-base balance of army rations MILLIGRAMS PER RATION REACTION PRO- CAMP ORGANIZATION =r ee ae Ca P Fe eee Hoes RIES cc. N/1| cc. N/1\per cent Bowles eae aces 13 20h AS 572 | 2077 11 18 Chanute nent aecs co 260 ACIS: 1045 | 2600 6 13 MOOR Yee cot Sacto salabeo Bans 666 | 2615 | 37.4 | 19 16 IDG VeUSse esac nerve 301 F. S. Bn. 834 | 2138 | 25.7 9 12 Devenses eaten 303 F. A. 1060 | 2279 | 28.7] 12 ly TDK ee ies poUoe bP ma: 691 | 1983 14 16 5 Db. Cait, aioe Semmens eo as 307 F. A. 556 | 2085 | 26.7 i 15 HIN StOMss Meee eee cer C. & B. School} 780 | 2758 | 29.6 9 13 Greene ne), OF Or So minis 653 | 2428 | 49.4] 11 14 Greenleaf. 2:5: -4..2:6% Recr. No. 1 513 | 1645 28 10 JACKSON say hep. tee Off. Mess B. H.| 782 | 1874 13 13 JohRston. 482) = tot: Mess Co: No. 1} 759 | 2229 24 14 Reeamnyreciy cece ese 134 F. A. 685 | 1808 24 14 Meet ne eae 320 Inf. 643 | 2181 | 29.6 | 18 14 McClellant.) 32) 0.4) 12 Se AS 833 | 2065 | 30.2 4 i Rockwellii:.5. 2.62 25. s63) Ins: 583 | 2140 | 29.1 13 16 SOVIE?. 2c. ceri tase yah al OO aeNe oe 649 | 2482 | 29.7 | 15 12 Selfridge pao eri see 40 Squad. 749 | 1915 | 24.0 15 11 Gordons a eee Pe ante 374 | 1516 | 22.8 0 0 15 Davis’... Secs oe. aah eel 00 ans Asie) 1075" |p2o.on loo 14 Rebly Ook Ah, See 324 Squad. 627 | 2103 | 26.9 24 13 remote. ..25 oe 12 Inf. 856 | 2050 | 30.3 1 12 PUAMIOT AS ae carte ooe Pa 956 | 2845 | 43.3 6 15 Staid.. 4s. wack ao. 4| 2o2 Squad. 695 | 2092 | 27.7 |, 12 15 MI oc a -i52®.s sss || OU 573 | 2170 | 26.2 if 19 Wadsworth............| 107 Inf. 508 | 1992 | 24.3 : 1 15 C@hanutew”, 22. 22) | 2689Ae's: 868 | 2340 | 27.5 2, 16 Gerstner. 24/2 ic OSE 43 Squad. 659 | 1732 | 20.3 15 Tewis«s4al.-62.aaieee2 | 662D ab. 996 | 2632 | 34.4 20 15 azelhurst....2.. cose |leDU@e aes 704 | 2215 | 29.4 13 13 Wangliss. het say. oc War prisoners | 717 | 2130 | 25.0 25 13 Warteouver..-.55-.. «5, 404 A. Squad. 687 | 2402 | 26.7 | 19 14 Amersgen. io: scre-baiss.. laptacieerstee et ee lade e2E 719129 1 14 Sherman’s Standard .................| 680 | 1440 | 15.0 ACID-BASE BALANCE OF ARMY RATIONS 569 he purchases foods in the open market which give variety and, in- cidentally, serve to introduce larger amounts of the base-forming elements.1 Table 1 shows in cubic centimeters of N/1 solution the excess of acid or base in the rations of various organizations from many camps. These values were obtained by determining the average amounts of all foods consumed per man per day for a period of seven days. Acid and base values were calculated from Sherman’s tables. It is seen that some of the diets are strongly acid-forming, some about neutral and others contain an excess of base. There is, undoubtedly, a tendency for the rations, as actually consumed, to be acid-forming in character. The rations were found to contain more calcium, phos- phorus and iron than the standards proposed by Sherman require. TABLE 2 Acid-base balance of rations, Camp Cody EXCESS | EXCESS DATE ORGANIZATION Ca | P | Fe | acrp | Base mgm.|mgm.|mgm.| cc. N/1 | cc. N/1 August 3-9, 1918......... Co. H, 135th Inf. 539/1790|22.1|} 30.2 August 3-9, 1918......... Co. I, 135th Inf. 416}1671/22.0| 21.2 August 3-9, 1918......... Comin. 1acth Int. 473]1662/21.0} 21.5 August 3-9, 1918......... GoM.) 135th Int. 542/1801|21.3} 19.1 August 11-17, 1918....... Liquid Diet, Base Hosp. |1279/1240/67.0 21.0 August 11-17, 1918.......| Light Diet, Base Hosp. | 872/2087/28.0 25.0 August 11-17, 1918....... Patients’ Mess, Base Hosp. 680) 1585/23 .0 2.0 Examination of base hospital dietaries reveals the interesting fact that base-forming elements are practically always in excess. Table 2 shows the acid-base balance of the rations of four infantry companies and of the base hospital diets at Camp Cody (data supplied by Capt. Paul E. Howe). This condition, perhaps, is more strikingly exhibited in a study made at the Base Hospital, Camp Custer, by Lieut. C. N. Frey, who undertook this work aided by the great interest of Lieut. Colonel Irons, the Commanding Officer. Table 3 indicates that the convalescent patients had only one of seven days in which the acid- forming elements of the food were in excess of the base formers. It seems significant that these hospital dietaries show such a marked contrast with many rations consumed by the well soldier. Is this alkaline reaction of the dietaries of the sick merely a coincidence, or 1 Since April 1, 1919, all supplies have been obtained from the Quartermaster. 570 N. R. BLATHERWICK has a process of selection hit upon the seeming fact that neutral or base-forming diets are best suited to the needs of convalescents? The greater amounts of bases in hospital diets are secured by a more ex- tensive use of milk, fruits and vegetables. The possibility that the continued use of acid-forming diets may lead to a greater susceptibility to diseases of the less infectious type has seemed worthy of investigation. The statement of Hindhede (2) regarding his children who are vegetarians may be recalled, “I may add that with the exception of whooping cough and measles, which attacked them very lightly, and a slight tonsillitis in one of them, I do not recall that any of my children have ever been really ill.” TABLE 3 Summary of ration study, convalescent patients’ mess, Base Hospital, Camp Custer CALORIES | ANIMAL WEGETAS - EXCESS EXCESS DAY BLE PRO-| PROTEIN (TOTAL) | PROTEIN ae ACID BASE De Poa ros eee Mondaiye) cits .secdgaes pes 3175 74.4 25.6 119 1.8 Muesda ye te ley oe-s saclyaa.4| 4208 65.1 34.9 117 15.6 Wednesdaya.. 4..:cShsnence. 3673 67.7 S20 122 0.7 DHUYSaay sre. ge teepe nn. 4418 59.0 41.0 146 113205 BEA AY,: hive .c chp Set eee 2855 61.3 38.7 109 4.1 Saturday. .... jasc eeaeesen 4| 13690 59.2 40.8 109 25.0 Sundays oe cae eons weteZO 76.0 24.0 132 24.4 IAVCTA PCs eec ees | OoUse 66.1 33.9 122 30.6 * Foods contributing base: potatoes, spinach, milk, beans, figs, apples. Chittenden has also reported a better state of health when living on a low protein diet. ‘At Camp Wheeler, conditions seemed favorable for undertaking an investigation of the possible relationship of diet to disease. During the winter of 1917-18, this camp had numerous cases of measles, mumps, influenza and pneumonia. When Nutritional Survey Party no. 8, under the leadership of Major H. A. Mattill, arrived there last spring, we were impressed with the peculiar dietary habits of the soldiers. A preliminary examination of the bills of fare showed that many organizations were consuming about one pound of meat per man per day and only about one-fourth pound of potatoes, instead of the usual pound of this food. Potatoes, with their alkaline ash, were substituted by rice and hominy, with their excess of acid-forming ACID-BASE BALANCE OF ARMY RATIONS 571 elements. Chart 1 shows the relationship found between amounts of meat supplied and the duration of disease for fifteen companies of the 124th Infantry during February and March, 1918. A rough parallelism is indicated. Or Duration ef disease and meat Q supplied compared in warieus comamies of 124 Inf, 6 Grepls shown in “AX , ya, Smoothed SD Fig. 1. A, Duration of disease and meat supplied compared in various com- panies of 124th Infantry; B, graphs shown in ““A”? smoothed. Solid line repre- sents amount of meat supplied the messes, one scale division representing 4 pounds. Dotted line represents duration of disease. The author studied the food consumption of certain organizations at Camp Devens during the epidemic of influenza-pneumonia. The three companies of the 36th Infantry with the lowest influenza rates and the three companies having the highest influenza rates failed to show any relationship whatsoever to the amount of excess acid in the rations (excess acid varied from 6.8 to 31.8 cc. N/1 solution per man bi N. R. BLATHERWICK per day). Neither was any relationship between influenza rate and calorific intake or the partition of the calories indicated. It is extremely difficult, one might say impossible, to demonstrate any such influence in the case of influenza. The virulence of the organism or organisms is so great as to sweep away all ordinary powers of resistance. The results obtained at Camp Wheeler are suggestive of a possibility that an acid-forming diet consumed for long periods of time may lead to a greater susceptibility to disease of the less infectious type. Those who have control of the feeding of the large numbers of persons in our public institutions might well undertake an investigation of this problem. In such institutions the necessary control of the diet and of the other factors should be more easily obtainable than in the army. BIBLIOGRAPHY (1) BuatHerwick: Arch. Int. Med., 1914, xiv, 409. (2) HinpHeEpe: Protein and nutrition, London, 1913, 8. DRIED VEGETABLES FOR ARMY USE SAMUEL C. PRESCOTT From the Section of Food and Nutrition, Division of Sanitation, Medical Department, United States Army Received for publication June 3, 1919 A famous wit once remarked that there is nothing new except what has been forgotten. The period since 1914 has proved the aptness if not the truth of this remark, for the conservation of food by drying has been strongly urged as a “‘new”’ method, whereas in reality it is perhaps the oldest method of preserving foods extant. Even in their relations to army subsistence we cannot claim that the dried or, as we now are more likely to speak of them, “‘dehydrated,”’ foods can claim the quality of novelty for they were used to some extent in our Civil War, and to a considerable extent by the British Forces in the Boer War, and had been largely used by the Allies before the United States became an active participant in the struggle of the past few years. It is true, however, that the European war has forced on our atten- tion the possibilities of drying as a commercial process of food preserva- tion in much the same way that the Civil War emphasized the great applicability of canning to the general problem of subsistence. By “dehydration” is understood the rapid removal of water from vegetables, fruits or other foods through evaporation by the use of air currents or vacuum combined with moderate heat, to such an extent that the resulting product generally feels dry to the touch, and is hard, brittle or condensed in character. Dehydrated vegetables do not contain in general more than 10 per cent of water. The cellular structure should be unchanged, the membranes remaining intact, and the cell contents losing only water. When cooked they will re- turn to approximately the bulk, appearance and character of the material before drying. If prepared properly the color, flavor and texture of the products when cooked will be essentially as in cooked fresh material. 573 574 SAMUEL C. PRESCOTT The vegetables here considered include those ordinarily purchasable only in fresh, green or canned condition, and do not include mature dried beans, peas, lentils, corn or other vegetables of similar character. During the Civil War desiccated vegetables in compressed form were used somewhat sparingly with the intent of improving the army ration from a hygienic standpoint, and especially as a means of pre- venting outbreaks of scurvy among the troops fed almost continuously on salt pork, salt beef, hard bread and the few vegetables which could be secured in the surrounding country. Some of the desiccated foods were said to be good while others were said to be very unpalatable. Among the anti-scorbutics issued to the Army of the Potomac in three months in 1864 were 600 pounds desiccated potatoes, 5320 pounds mixed vegetables and 551,812 pounds dried apples. The following extract from the report of operations of the Medical Department of the Army of the Potomac from its organization in July, 1861, until the change of Base to the James River in July, 1862, by Surgeon C. 8. Tripler, U. S. A. Medical Director, shows the faith which was placed in the use of these products as a means of preventing scurvy: While still at the White House, I received a telegram from the front that seurvy had appeared in two brigades of the Army one of which were the regular troops. I could scarcely credit the accuracy of the information. I knew that the brigade had obeyed the orders issued in relation to the use of vegetables, and the manner of cooking their rations; still I did not think it prudent to disregard the report, and accordingly I felepraphied to Washington for lemons and potash. 3 ; I investigated the report with regard to scurvy and found it ds Wee erroneous. I, however, requested the Adjutant General to compel the men to use desiccated peneanite ‘add to make soup daily. eee : General Dana says he cannot comprehend ve the men should have scurvy with their present ration; but I am informed that the desiccated vegetables are so disagreeable to the taste that the men cannot eat them. Antiscorbutie ordered. During the Boer War dried soup vegetables which had been stored in paraffined barrels for over fifteen years, were used by the troops, thus indicating the keeping quality of these dehydrated products. For about a year and a half I have had opportunity to study products prepared by a large number of methods, as manufacturers have sent them to Washington for possible sale to the Government for army use. There is a marked difference in products which have been studied. They have been examined as to: DRIED VEGETABLES FOR ARMY USE 575 a. Physical appearance. b. Soaking back properties, whether good, bad, fairly rapid, or very slow. c. Keeping quality. Danger of invasion by moulds, bacteria and insects. d. Action of enzymes. e. Absorption of moisture from air. f. Cooking quality. Retention or loss of flavor. g. Effect of type of container on the character and keeping quality of the foods. As has been stated, marked differences have been noted. The causes for these differences may be referred to age and quality of raw materials, methods of pre-treatment, methods and time of drying and conditions of storage after drying. It may be stated that to secure good dehydrated vegetables the raw material should be fresh and of first-class quality. The pre-treatment by steam or hot water dipping should be brief and carefully managed to avoid excessive changes and the time and method of drying should be so regulated as to prevent intense surface evaporation at the beginning of the drying period with the consequent ‘‘case hardening” or sealing over of the surfaces so as to prevent rapid loss of the water from the inner tissues. In a report to the Surgeon General in January, 1918, I pointed out certain advantages which might accrue as a result of the extensive use of dried vegetables and fruits in army subsistence. Most of these advantages were economic and a few were distinctly nutritional. The principal gains from such use were: . Lower cost of actual units. . Great saving of space in transportation. . Guaranteed keeping quality with no loss by freezing or spoilage. . Saving of storage space and labor in camp. . Wider range of vegetable foods. . Generally improved diet, through increase in roughage, alkaline salts and variety of combinations possible. In the early part of the war some apprehension was felt regarding the use of these products, and while this fear was unnecessarily great it was based on certain sound observations. The ordinary dried vegetables before the war were neither attractive in appearance, appetizing in flavor nor good in food quality. Improvements have gradually taken place in the methods of preparation during the past four years, however, and while the bulk of material made is still in- Ooowr Wd 576 SAMUEL C. PRESCOTT. ferior, it is possible to secure some dehydrated products of excellent appearance and flavor closely approximating that of the cooked fresh vegetable, and of practically unimpaired food value. This improve- ment has been brought about by the recognition of the fact that a dehydrated food is not merely dried, but the drying must be done in such a way as to preserve cellular structure, prevent undue decom- position by heat, and forestall changes by microbic agencies or by oxidizing, proteolytic or sucroclastic enzymes. Attention must also be paid to the age, quality and soundness of the raw materials and to the methods of preparation, rate of drying and sanitation of the finished product. During the past two years there have been shipped for our forces overseas approximately 40,000 tons of these products, principally pota- toes, but also carrots, turnips, onions and large quantities of soup mixtures of six to eight or more vegetables. While no special reports on the use of these products are obtainable at this time, I am indebted to officers of the Quartermaster Corps for the statement that these dried foods have resulted in great saving in labor and have been found fairly acceptable to the men, satisfactory to the subsistence officers and cooks, and in general an excellent and easily handled form of vegetable food. This too in spite of the poor quality due to haste in manufacture to meet the emergency, and a letting down in specifications. Extended studies conducted by the Section of Food and Nutrition of the Surgeon General’s Office, and later by the Division of Dehy- dration of the Bureau of Chemistry have shown that from the stand- point of general use in large masses, chemical analysis, fuel value and maintenance of bodily strength, properly made products are practi- cally equal to fresh materials. Reports from a number of army hos- pitals and camp messes have demonstrated their practicability. The main question from the nutritive standpoint is in relation to antiscorbutic and growth-promoting properties. During the siege of Kut in the Mesopotamian Campaign it was reported that some of the British forces were afflicted with scurvy as a result of the con- stant and exclusive use of dried foods. Animal investigation with guinea pigs has shown that a diet composed entirely of dried vege- tables of non-acid character is greatly weakened in antiscorbutics or has lost them altogether, while with dried fruits of acid character, such as tomatoes, oranges and lemons, scurvy does not result even after long continued feeding. With rats different results are obtained DRIED VEGETABLES FOR ARMY USE ya and it seems to be practically impossible to produce symptoms of scurvy with any dried vegetables, if I am correctly informed. The bearing of these results on the use of these foods for the army, while of interest in, a general way, is of secondary importance for it is only under most unusual conditions that a diet would be made up entirely of dried foods and then only for limited time periods. No experiments have been conducted on human subjects as would seem to be extremely desirable before we come to any final conclusion as to the deficiencies of these dried foods in antiscorbutic substances when applied to general use. The findings are of sufficient interest, however, to stimulate investigations for the purpose of discovering whether slight changes in the method of preparation or drying may not entirely overcome this academie objection and plans are now being formulated to take up these investigations on a large scale by the Division of Dehydration. Whether the mere presence of oxy-acids of the malic type is sufficient to prevent scurvy is problematical, but at least it seems probable that foods designed for use in localities where it is impossible to secure any fresh material ean be so treated by changes in pre-treatment, by fermentation or otherwise as to secure the necessary antiscorbutic substance. With a reduetion in weight amounting to 90 per cent in most cases, a reduction im bulk amounting to more than 50 per cent and a guarantee of keeping qualities for long continued periods and the obviously greater ease of transportation, the military advantages in the use of these foods are so great that there can be no doubt but the army will constantly make use of them in increasing quantity for all expedi- tionary forees and in posts and camps during the winter and when an abundant and cheap supply of fresh materials cannot be obtained. THE AMERICAN JOURNAL OF PHYSIOLOGY, VOL. 49, NO. 4 AMERICAN MILITARY HOSPITAL DIETARIES! R. G. HOSKINS From the Section of Food and Nutrition, Division of Sanitation, Medical Department, United States Army Received for publication June 3, 1919 The problems of military hospital nutrition are, in general, much like those of any large institution, i.e., problems of supply, preparation and distribution. There are, however, certain features in the military hospitals not generally observed in civilian institutions. These arise mostly from the superposition of a military regime on that of an ordi- nary hospital. The proportion of patients who are practically well and merely waiting for discharge is notably higher in military than in civilian hospitals, these being essentially normal men, temporarily in confinement. The per capita food consumption, therefore, averages relatively high. The fact that the patients are subject to a high de- gree of arbitrary control is also reflected in totals of consumption and waste. Although there are certain variations in details, the general plan of administration of the base and general hospitals in this country at present is much the same in all. Directly under the commanding officer is the mess officer, usually either an experienced hotel manager, or a former army mess sergeant commissioned in the Sanitary Corps. Associated with him, sometimes under his immediate direction, and sometimes immediately under the commanding officer, is the dietitian. She usually has one or more assistants. The dietitians are, for the most part, women who have had courses in domestic science, but who often have had little or no previous training in hospital work. The mess officer has the assistance of several sergeants who deal with such 1 The quantitative data herein reported have been collected by several survey parties of the Section of Food and Nutrition, Office of the Surgeon General. Since thirty or more individuals have contributed, it is not feasible to assign credit, except for certain specific studies. The field notes added by the writer have been accumulated in the course of nine months’ study of nutritional prob- lems in some fifty military hospitals. 578 AMERICAN MILITARY HOSPITAL DIETARIES 579 matters as supplies, accounts and kitchen and dining room manage- ment. The actual preparation of the food, and the care of the utensils and the premises are attended to by cooks, usually enlisted men, and kitchen police. Separate messes are typically maintained for sick officers, nurses, enlisted men, patients and hospital corps men. The officers’ mess proper, and the nurses’ mess are usually quasi-independ- ent institutions, in which, however, the mess organization takes a benevolent and codperating interest. In theory, at any rate, dietetics is a branch of therapeutics, and each soldier in the hospital should receive the diet best adapted to his case, just as he should receive individual therapeusis in other respects. Practically, however, conditions have not permitted any- thing very closely approximating this ideal. It is true that occasion- ally special diets are encountered, which have been devised for individual patients, but for the most part, conventional “lights,” “liquids” and ‘‘regulars’”’ are provided for the men in large groups, with, in some cases ‘‘softs’? interposed between the “liquids”? and “lights,’’ especially for the surgical convalescents. This is not an ideal state of affairs, but under existing conditions is probably as sat- isfactory as can be hoped for. The problem then resolves itself into one of best utilizing this system to secure for each patient the diet best suited to his individual needs. Exclusive of officers and nurses, there are, from the point of view of dietetics, at least eight classes of individuals to be dealt with. These are: 1. Normal men at fairly active work, needing approximately 3600 calories daily. 2. Normal men at sedentary work, needing approximately 3200 calories each. é 3. Convalescent patients, metabolically normal, walking about the wards and requiring approximately 2600 calories. Aside from a rather low caloric demand, there are no special indications to be met in the diet of this class. 4. Bed patients, metabolically normal, requirmg approximately 2000 calories. This class is usually over-fed, receiving meals intended primarily for class 3, or even classes 1 and 2. 5. Sub-acute febrile patients, those with empyema especially, need- ing high caloric and high-protein feeding. Experience at Camp Lee has shown that empyema results in a constant drain on the body nitrogen, which should be compensated in the diet. The specific 580 R. G. HOSKINS dynamic action of protein is probably also of importance in this type of patients. 6. In this class may be included a considerable variety of patients who are not sufficiently ill to receive special diets, but whose con- valescence could be hastened by careful attention to their dietaries. They include convalescents from pneumonia, and others in poor physical trim, who need a fairly generous diet, but who, from lack of appetite, eat but sparimgly. Such patients should have meals planned especially for attractiveness and high caloric content. A common practice is to give these men the ordinary regular diet, sup- plemented by egg nogs and other special foods between meals. This is a makeshift device, which has obvious defects. 7. For that class of patients troubled with constipation when not actively exercising, a diet including especially laxative components should be provided. Rather than establishing a special diet for this type of patients, however, the situation could be met fairly well by deliberately making the meals of all regular patients laxative. The routine use of cathartics in the wards is a reflection upon the dietitians. 8. There is, of course, a special group of diseases, including ne- phritis, diabetes, cardio-vascular disorders, gastro-intestinal and acute surgical cases, which by general consent must be treated by special dietary therapeusis. The problem of meeting the needs of such cases does not ordinarily confront the mess administration, since the diets usually are, and should be prescribed by the surgeons in charge. In table 1 are included the quantitative data available on food consumption in army hospitals and medical organizations. The number of rations upon which the study in each case is based, is stated in column 3. This, it will be seen, varies from 131 to 15,897. The ration, it might be stated, comprises the food of one man for one day. The studies have usually been carried out for a period of one week. In making such studies, the general plan has been to invoice the food ma- terials in the kitchen and store rooms at the beginning of the study, to record all accessions during the period, and to make a second inventory at the end. Subtracting the amount at the second inventory from the sum of the first inventory and the accessions gave the food used during the period. From this were subtracted the various components of the garbage, giving the actual consumption during the period. In certain of the hospital studies, a more direct method of weighing the food actually used was more practicable. TABLE 1 yA ie : lo a iS) 2G DISTRIBUTION rs) = Sanit ¢ ia ea TYPE OF Ay air ee EDIBLE PATIENTS oon || ae = es a8 A a & WASTE ORD Aas P. F Cc 5 USPS OB AR ES Eka | 50a a | a3 = z S | 5 per | per | per : cent shi ok t | cents pounds Eiguid diets: .... 0.52: Base 537 | 900) 14 | 36 | 50 |17.37/19.30| None ‘ ‘ Ba 2,254 | 2,535 3 F .97/13 .9: Tight diets... se 204 | 2,535 | 13 = 63 |41 9718.98 0.78 Base 1,480 | 1,916 | 16 | 33 | 51 /47.31/20.06} 0.68 Base 5,341 | 2,743 | 13 | 29 | 58 |46.06/13.40| 0.98 Base 614 | 3,458 | 12 | 35 | 53 |48.23])12.12) 0.72 Base 709 | 3,242 | 11 | 36 | 53 |39.83/10.84) 0.91 Base 236 | 3,906 | 14 | 34 | 52 |57.90/13.74) 0.48 Base 728 | 3,043 | 13 | 35 | 52 /45.64)12.44) 0.96 Base 4,516 | 3,270 | 14 | 37 | 49 |55.13/14.85} 0.68 Base 10,125 | 3,165 | 12 | 34 | 54 |45.48/12.18) 0.73 Aviation 131 | 2,986 | 15 | 38 | 47 |54.14/17.19} 0.18 \ E 4,109 | 3,788 | 13 | 33 | 54 |55.34/14.61) 0.22 Regular diets....... | Base 3,338 | 2,759 | 12 | 34 | 54 |52.20/14.53) 1.16 AveTage..... 0.62. e)...5.....| 29,827 | 3,236 | 13 | 35 | 53. |49.99)13.59) 0.70 Officers’ ward......... Base 137 | 3,570 | 15 | 39 | 46 /77.47|18.65) 0.71 General | 2,391 | 3,629 | 13 | 30 | 57 /43.03)11.17) 0.30 Patients and corps }| Aviation| 318] 3,998] 10 | 36 | 54 |55.73/13.15} 0.29 men combined.... | | Base 3,310 | 2,624 | 17 | 32 | 51 [39.50)14.32) 0.19 Field 386 | 3,605 | 13 | 26 | 61 |35.42) 9.48) 0.19 Average............|.........| 6,405 | 3,464 | 13 | 31 | 56 |43.42/12.03] 0.24 Non-patients Meds Det. .ie.cz.: Base 2,581 | 3,863 | 12 | 39 | 49 [59.05/13.78) 0.53 INurses.............2....|, Base 791 | 2,859 | 14 | 31 | 55 |40.72/13.01| 0.35 Hosp. Det........| Base 1,392 | 3,472 | 12 | 24 | 64 |36.89| 9.54|No data EGsp-)Dety.......| Dase 1,863 | 3,682 | 14 | 29 | 57 [51.26/13.68) 0.20 Offieerses1, 25. Base 513 | 3,695 | 12 | 39 | 49 |52.58/13.96} 0.91 122-106 S. Tr.....| Field 354 | 3,714 | 13 | 34 | 53 |54.11/12.37) 0.84 123° 1 Hospe:b.a. Field 248 | 4,047 | 14 | 36 | 50 |57.08)12.67| 0.64 FP. Hosp....2.....| Field 519 | 3,407 | 14 | 32 | 54 |35.89/10.07; 0.238 141 F. Hosp.......| Field 556 | 3,387 | 12 | 35 | 53 |40.15/11.60} 0.09 Hosp. Corps: .. °°: Aviation 187 | 4,522 | 13 | 31 | 56 |58.50)12.58) 0.12 We ACTA... 15,897 | 4,052 | 15 | 39 | 46 |67.58/14.72| 0.80 Sanitary Co...... 1,148 | 3,638 | 13 | 31 | 56 |47.80/11.73) 0.71 Sanitary Co...... 1,467 | 4,145 | 13 | 25 | 68 |44.40/ 9.97) 0.64 para CO oe 697 | 4,637 | 13 | 31 | 56 |51.50/10.68} 0.19 PATO. COs. 2 275 0! coe 841 | 4,880 | 12 | 41 | 47 |51.91/10.21) 0.32 AI, 0.0... sce 399 | 3,778 | 11 | 36 | 53 39.66) 9.77) 0.35 Amb Cowl. .!. 22% 714 | 2,992 | 14 | 33 | 53 |48.07/15.54| 0.09 amie Co.) . 10. 819 | 4,000 | 13 | 30 | 57 |46.67)11.34) 0.17 PME Cnt os «: 723 | 3,962 | 14 | 34 | 52 |55.12/13.51) 0.22 Average............|.....-...| 31,709 | 3,828 | 13 | 33 | 54 /49.94/12.14) 0.39 Average of 427 army messes.......... (3,633 | 14 | 31 | 55 '47.26/13.01] 0.38 582 R. G. HOSKINS One study of liquid diets only is available. In this the caloric con- tent amounted to 900, with a fairly normal distribution of protein, fat and carbohydrate. Such diets are generally used for but a short time, and from a nutritional point of view often amount to little more than agreeable fluids. Light diets in two hospitals, including 3734 rations, were studied. The caloric consumption in one was 2535, and in the other, 1916. The protein components amounted to 15 per cent as compared with an average of 14 per cent in 427 army messes elsewhere summarized. The fat components averaged 29 per cent, as compared with 31 per cent in | the average army mess. Even this proportion seems somewhat high, however, for a “‘light”’ diet. The fact that such diets usually com- prise considerable amounts of milk and eggs accounts for the cost of 45 cents per day, as compared with 47 cents for a full 3600 calorie ration. The edible waste in this group amounted to 0.73 pound per man per day. This is somewhat high as compared with average hospital waste, and is about twice that of the average army mess. This is to be ascribed partially to the capricious appetites characteristic of men ill enough to require light diets and partially to inefficiency in serving. This waste can be held at a much lower level. Of the regular diets, ten studies are available, comprising 29,827 rations. The caloric consumption varied from 2748 to 3906, averaging 3236. The protein and carbohydrate components were slightly be- low the army average, while the fat component amounted to 35 per cent as compared with 31 per cent in the average army mess. This is to be ascribed partly to a higher consumption of butter and cream, but also, unfortunately, partly to unskilful dietaries in which greasy food played apart. The edible waste in this group was 0.7 pound per man per day. Experience at the Camp Custer Base Hospital has shown that the edible waste can be held below 0.3 ounce per man per day. Only one study of a sick officers’ ward is available. This comprised 137 rations. The caloric consumption amounted to 3570, which is probably somewhat below the average for this type of patients. The writer has been struck by the frequency with which officers in hospital systematically overeat. Heavy breakfasts, such as bacon and eggs, cereal with cream, fruit, potato and coffee with cream and sugar, are the usual type. The dinners and suppers are correspondingly generous. The fat consumption in the study reported, it will be noted, is 39 per cent, as against a general army average of 31 per cent. It is generally recognized by the dietitians and mess officers that such diets AMERICAN MILITARY HOSPITAL DIETARIES 583 are highly improper for sick men, but the demand is insistent, and officer patients are likely to get approximately what they want. The edible waste in this particular study was 0.7 pound per man per day. This is probably less than average. No specific figures are available, but the waste in the officers’ messes is notoriously higher than that of others inthe army. The cost per day in this case was 77 cents, whereas the allowance for this type of patient is $1.00 per day. In a considerable number of hospitals, owing to ignorance and in- dolence in some cases, and to lack of equipment in others, the hospital attendants and the patients have been fed the same meals. Four studies of such hospitals are available, comprising 6405 rations. The calorie consumption was 3464, which is intermediate between that of patients proper and of medical personnel. The fat consumption was normal; the protein slightly low and the carbohydrate correspondingly high. The waste in this group averaged 0.24 pound per day. This favorable figure is not representative of this type of mess. The highest waste seen in any hospitals has been found in those in which the sick and well men are fed together. In one case it amounted to approxi- mately 2 pounds per man per day. Of non-patient groups, nineteen studies have been treated together. These mnclude medical detachment, nurses, officers, sanitary train, field hospital, ambulance section and ambulance companies, giving a total of 31,709 rations. The caloric consumption varied from 2859 to 4880 averaging 3828, and the distribution of protein, fat and car- bohydrate was approximately normal but with fat slightly high. The cost per day and the edible waste per capita were slightly above the army average. In the nurses’ mess it will be noted that the caloric consumption amounted to but 2859, distributed in exactly the ratio found as average in 427 army messes. It is believed that this mess is fairly typical of its kind. An officers’ mess comprising 513 rations is also included; in this class the caloric consumption was 3695. Observations in more than 50 such messes have convinced the writer that this amount is lower than average. It has been a matter of some interest to note the dietary idiosyncracies of medical officers. Over-consumption and inadequate balance are so common as to constitute the rule rather than the exception. The high wastage in such messes has been previously commented on. 584 R. G. HOSKINS In table 2 are summarized the results of a detailed ration study, made by Lieut. C. N. Frey at the Camp Custer Base Hospital. This table is interesting as showing the variability of a mess from one day to another. The low figure of 2855 calories consumed on Friday is to be ascribed, probably, to fish for dinner and for supper. This com- modity is usually unpopular. In this hospital a special study has been made for months of the technique of waste control. The patients are well fed and contented and wastage almost eliminated. The edible waste for the week studied amounted to 0.26 ounce per capita daily, a quantity which might well serve as model for any institution TABLE 2 Summary of ration study a jeile le lela le le fe_[gasl a z 2 a By By], Bb {A |S |gep<| & 4911S #1laa/ai8 /a hal ® 2| Sue : 2 | ee eee eae 2 ° Salts a = Gal] e Be ax a bl ch ea tele g2le |°slseaz| $4 » 1ez| ° (Bele |ezls al=8| clcoal SB 18at Ee |BSIa |4ele |BSl|Fsifea\e"a| oo /°6| 6 |°e|82/86/8,./ee/se/ 28/8 §] es a) e2 |.e-| os ee ee) oA Se ee a aSes| <3 al ala a a 2) = a 2 5 = iS} a ms iv me a Be oO _ iS) m fo) 0S 175 [hy nee eee 3175) 15 | 39 | 45 | 74 | 26 |4.76) 667/0.37|16.0/0.50 MUGS Oa he ei crear 4258] 11 | 47 | 42 | 65 | 35 |6.04 eee 11.0)0.25 Wednesday........... 3673} 14 | 37 | 49 | 68 | 32 [5.65 650/0.20 8.0/0 22 Thursday............|/4418} 14 | 43 | 44 | 59 | 41 (6.16 ee isa Friday...............{2855] 16 | 28 | 56 | 61 | 39 |5.60 510/0.25 8.0/0.28 Saturdagotd .-istast 3690) 12 | 35 | 53 | 59 | 41 (5.69 6470.25 10.0 ; Sunday............../8420) 16 | 38 | 46 | 76 | 24 |6.02| 5590.25) 9.0 RV CURL Cote onashakietes 3638] 14 | 38 | 48 | 66 | 44 15.70 639 0.26 10 .3,0.305 121.85 or any home kitchen. This amounts to approximately 20 pounds of edible waste per thousand men, or 10 calories per capita. In table 3 is summarized the result of a special study made by Lieut. A. G. Hogan in an ambulance company. The records of the men showed their weights at the time of enlistment; second weighings were made in connection with this study. It was found that the men had gained during their six months’ service from September to March, an average of nine pounds each. The average height of the company was 172.8 cm.; the average weight was 67.3 kgm; the surface calculated by the DuBois formula amounted to 1.81 sq.m., giving a basal metab- olism of 1725 calories. The total metabolism by actual quantitative AMERICAN MILITARY HOSPITAL DIETARIES 585 determination of the food consumption amounted to 3778 calories, leaving a difference of 2053, representing the activity metabolism. During the week of the study the weather was moderate, the time and place being early spring in Kentucky. The men in this company were by previous occupation mostly farmers and laborers. TABLE 3 Metabolism of ambulance company, March 4, 1918 Gain in weight gas service,—September to March............ 9.0 pounds Average height. . 172.8 cm. Average weight.. eros 67.3 kgm. Surface, Du Bois penis 1.81 sq. m. Basal metabolism. . iL eee ... 1725 ealories Total metabolism, oy CeRSINEN . 3778 calories ee areas) es) WT 2053 calories Sixty-two men studied one week. Work, moderate; temperature, moderate. Previous occupation, largely farmers and laborers. TABLE 4* Average daily expenditure for certain foods for six months. August, 1918, to January, 1919, at Base Hospital, Camp Kearny, California FRESH TOTAL TOTAL meee eee) sect PPE rere | VCE | ee | Oe ee Se as pry 5.5¢| 7.3¢ | 3.4¢ 1 1.9¢ | 4.3¢ | 2.8¢ [88.3¢ | 56.4¢ auents Mess | 123.3%! 9.7%| 12.8%] 6.0% 3.4%] 7.6%! 5.1%|68.0%|100.0% Detachment’s gt 4.4¢ | 0.8¢ | 3.4¢ | 3.8¢ | 3.4¢ | 2.0¢ |35.4¢ | 48.6¢ mess. 36.1%| 9.0%] 1.6%§| 6.9%] 7.7%] 7.0%] 4.0%|72.0%|100.0% oh _ [[83.8¢ | 8.3¢ | 12.9¢ | 6.5¢ | 9.9¢ | 6.9¢ | 1.7¢ |80.0¢ |101.0¢ cers” MESS... | lg5 407] 8.2%] 12.7%| 6.4%| 9.7%| 6.8%) 1.6%|79.0%|100.0% N f\10.3¢ | 3.3¢ | 6.6¢ | 3.8¢ | 4.1¢ | 3.9¢ 32.0¢ | 46.1¢ PRR NSS): a Lace egal 22. 3%| 7.2%] 14.3%] 8.7%| 8.9%] 8.5% 70.0%|100.0% (Bote pe 87 gen- eral messes... . .|42.3%| 4.4%] Tf 3 hol. at 6.0%| 6.0%|62.4%|41.58% *Compiled by Capt. Paul E. Howe, Sanitary Corps, 7 Less than 1 per cent. t Including cream and ice cream. § Ice cream, only. 586 R. G. HOSKINS Although it is intended to supply at army hospitals everything needed for adequate nutrition, the actual ration allowance for the individual patient is, of course, arbitrarily fixed. One of the major problems confronting the mess officer, therefore, is how to spend a limited sum to the best advantage. In figure 1 is shown the relative expenditure for each of the 35 com- ponents most commonly used in 87 army messes. In table 4 is sum- marized the average expenditure in the Camp Kearny Base Hospital 29.) 0) a) Tole/ cost of meat-4z3 | EE Beef, fresh — 2210 Gumus Bread, so{t-op Goeleding beef, boron, Sausage EEE Mi), evaporated ~6.0 poultry, conned beef, fresh cor gum Bocon -5.0 vea/, fish ond ham) Gams Sugar -— 5.0 mmm ~Fotatoes white” 5.0 Gams oo - 4-4 mummmmem Scvsace - 4.1 ee COMPARATIVE C05) OF COMPONENTS mmm Beef, carncd-2.5 OF THE RATIO! wm Fork, fresh-Zo = @Em Lard-zo The quantity of each food used wes secwred by me Beans,dry-1.5 averaging the data from 61 messes and average cost of ration found fo be 41.58¢. The cost of each mB Jam-i4 individual Canponent 4/3 ere expressed as 9G Fish, fresh-1.5 percentage of averoge rofion cost of 4.58%. Flour-1.3 Food prices are based on QM pricc list for Corn, canned-1.2 March, /919 at Nashinglon Borracks, D.C. Feas, Conned~1.2 Break{ast foods —I.t Fish, preserved- .9 Votatoes,sweer-39 Cheese - 8 Macaroni- 1% Sirup-% Oatmeal —.6 Feaches-.6 Prunes-.© Rice-.5 Hominy-3 cornmeal-2 me = veal-1.5 Fig. 1 for seven items comprising about 70 per cent of the total expenditure. These are based on daily determinations for a period of six months. This study was made by Capt. Paul E. Howe. Figure 2 represents graphically the relative expenditure for each of the seven items in the patients’, detachment’s, officers’, and nurses’ messes respectively, as compared with the result for 87 general army messes. It will be noted that the hospital expenditure for meat and for condensed milk was less and that for eggs, fresh milk, butter and fresh fruits materially higher than that of the army at large. The expenditure for fresh vegetables was only slightly greater in the hospital. AMERICAN MILITARY HOSPITAL DIETARIES 587 On the whole, the table indicates a nearer approach to a proper balance in the hospital than in the army at large. In this it is representative of hospital consumption in general. Percentile Expenditure for Certain Commodities Meat Rieti es 25.3 Detachment ome | (OC Offce’S a meee 90.4 Nurses ES TT 2 3 Eggs Fresh Fruits ArmyAverage mmm 44 Army Averages /- Patients =m 9.7 Patienis ma: 3.4 Detachment ==umemmmecen 7.0 Detachment smn 7.7 Officers =m 82 Officers ees 89.7 Nurses mmm 72 NurseS mums 86.7 : Fresh Fresh MitK_ Vegetables Army Average a {/- ArmyAverage Rea 60 Patient ue /2.% Patient samen 7. ( Detachment mmm /6 Detachment mmm 467.0 Officers =m /2.7 Officers ummm 6.8 Nurses ween | F 3 NorseS mmm &. 5 Butter Canned MilK ArmyAverage mmm J.7 ArmyAverage mmm 6.0 Patents quam 6.0 Patients cm«»< 5./ Detachment mmm 6.7 Detachment omms 40 Officers mmm 6.4 Officers mm 1.6 Nurses DSc 87 Nurses 0.0 Fig. 2 INDEX TO VOLUME XLIX A BDOMIN AL injuries, circulation in shock after, 90. Acacia, the pharmacology of, 137. Acid-base balance of army rations, 567. Adrenalin, circulatory failure due to, 345. Air concussion, physiological effects of, 121. Alcohol, concentration of, in tissues of hens after inhalation, 128. ALLEN, G. D. Quantitative studies on the rate of respiratory metabolism in Planaria. II. The rate of oxygen consumption during starvation, feed- ing, growth and regeneration in re- lation to the method of suscepti- bility to potassium cyanide as a measure of rate of metabolism, 420. Alveolar air, variations in, at low pres- sure, 119. American military hospital dietaries, 578. American Physiological Society, Pro- ceedings of, 117. AnpEerRson, R. J. The practicability of feeding a scientifically balanced ration in army camps, 523. Antiscorbutic properties of green malt, 145. Army camps, the practicability of feed- ing a scientifically balanced ration in, 523. —— rations, acid-base balance of, 567. —— use, dried vegetables for, 572. BABCOCK, E. B. See Carpenter and Bascock, 128. Becut, F.C. See Krerton and Becut, 248. 589 BEerGEIM, O. See Fisuspack, Smirs, Berceim, LicHTeENTHAELER, ReEH- Fuss and Hawk, 174. See Fisupack, Smita, BeERGEIM, ReEHFuss AND Hawk, 222. See MILLER, Fow.er, BERGEIM, Reuruss and Hawk, 254. See Smiru, FisHpack, BERGEIM, Reuruss and Hawk, 204. Beta rays from radium, relation be- tween velocity of, and their physio- logical effect, 127. Bile acids, metabolism of, 129. BLATHERWICK, N. R. Note on the acid-base balance of army rations, 567. Blood corpuscles, colorless, effect of shattered hemoprotein on, 127. —— flow, shock due to mechanical limitation of, 151. —— pressure, low, treatment of, after exposure of abdominal viscera, 137. —— volume, electrical conductivity to determine, 233. Body temperature, regulation of, and its relation to certain cerebral lesions, 271. Brain of normal and ataxic (?) pigeons, further studies on the chemical com- position of, 138. —— stem, studies on, 271. Brooxs, C. The effect of shattered hemoprotein on the colorless blood corpuscles, 127. (CALCIUM salts, quantitative study of effect of, on nerve, 497. Carpenter, T. M. and E. B. Bascocx. The concentration of alcohol in the tissues of hens after inhalation, 128. 590 Centriole and centrosphere, behavior of, in degenerating fibroblasts of tissue cultures, 123. Cerebral cortex, a comparative study of the relation of, to labyrinthine nystagmus, 141. —— lesions, regulation of body tem- perature and its relation to certain, 2i1. Cuitp, C. M. Susceptibility to lack of oxygen during starvation in Planaria, 403. Cicatrization of wounds, law of, 121. Circulation in shock after abdominal injuries, 90. , responses of, to low oxygen ten- sion, 118. Circulatory failure due to adrenalin, 345. CO: dissociation curve as the complete expression of the acid base equilib- rium of the blood, 117. Coir, W. C. C. See McCLEenpon and Cote, 145. Couuatz, F. A. See McCiEenpon and CouuaTz, 146. Coomss, H.C. See Pike, Coomss and Hastines, 125. Corr, O. M. See Lomparp and Cops, 139, 140. Crite, G. W. and H. R. Hosmer. Electric conductivity in relation to shock and exhaustion, 124. Crozier, W. J. Intra-cellular acidity in Valonia, 147. The control of the response to shading in the gill-plumes of Chro- modoris, 147. DPDECEREBRATE cats, observations on, 126. Dietaries, American military hospital, 578. Dinsmore, 8S. C. See Howr, Mason and Dinsmorg, 557. pu Noty, P. L. A device for injecting fluids intravenously, 122. INDEX pu Noijy, P. L. A new form of the Mohr’s specific gravity balance for small quantities of liquids, 123. An apparatus for measuring rapidly and accurately the surface tension of all liquids, 123. On the general expression of the law of cicatrization of wounds, 121. Dyes, vital benzidene, reaction of tis- sue cells to, 284. EGGS, gastric response to, 254. EISENBERGER, J. P. See Pratt and EISENBERGER, |. Electrical conductivity to determine blood volume, 233. Electric conductivity’ in relation to shock and exhaustion, 124. Exuis, M. M. Variations in respira- tion volume and oxygen consump- tion during the reduction of the oxygen tension and during short exposures at the reduced oxygen level, 119. ERLANGER, J. and H. 8. Gasser. Studies in secondary traumatic shock. II. Shock due to mechanical limitation of blood flow, 151. III. Circulatory failure due to ad- renalin, 345. R. Gesevt and H. S. Gasser. Studies in secondary traumatic shock. I. The circulation in shock after abdominal injuries, 90. FATIGUE, effect of, on bicarbonate content of blood plasma, 134. —, muscular tonus in relation to, 133. Feeding, oxygen consumption in, 377. Fisupack, H. R., C. A. Smits, O. Brr- ce, R. A. LICHTENTHAELER, M. E. Reuruss and P. B. HawxK. Gas- tric response to foods. III. The re- sponse of the human stomach to beef and beef products, 174. INDEX Fisopack, H. R., C. A. Situ, O. Bercem, M. E. Reuruss and P. B. Hawk. Gastric response to foods. V. The responseof the stomach to lamb and lamb products, 222. ——. See Smitu, Fisupack, BErR- GEIM, Renruss and Hawk, 204. FLORENCE, P. S. See Ryan and FLORENCE, 132. Food consumption, average, in train- ing camps of United States Army, 531. , muscular strength and, in army, 597. Foster, M. G., C. W. Hooper and G. H. WuireLte. The metabolism of bile acids, 129. Fow er, H. L. See Mitupr, Fowier, BrerceIM, Reuruss and Hawk, 254. Fraser, L., R. 8. Lane and J. J. R. Macteop. Observations on decere- brate cats, 126. Functional correlation of the hypo- physis and the thyroid, 55. : GASSER, H. S. See Ertancer and GassER, 151, 345. See ERLANGER, GASSER, 90. Gastric and duodenal ulcer, experi- mental, studies on, 148. —— response to foods, 174, 204, 222, 254. Genito-urinary organs, isolated, action of corpus luteum extracts on the movements of, 149. GESELL, R. See ERLANGER, GESELL and GassEr, 90. Gill-plumes of Chromodoris, control of response to shading in, 147. GitHens, T. S. and S. J. ME.LTzeErR. Phenomena following indirect con- cussion of the skull, 120. Glycogenolysis, relation of hypophysis to, 248. Grant, S. B. See Mupp and Grant, 144. GREENBERG, J.P. See Macut, GREEN- BERG and Isaacs, 148. GESELL and 591 GREENE, C. W. Studies on the re- sponses of the circulation to low oxy- gen tension. I. Types of variation in blood pressure and heart rate, 118. GREISHEIMER, E. A _ quantitative study of the effects produced by salts of sodium, potassium, rubidium and calcium on motor nerve of frog, 497. Growth, effect of pituitary feeding on, 238. HAGGARD, H. W. See Henper- son and Haaearp, 117. Hastines, A. B. The effect of fatigue on the bicarbonate content of blood plasma, 134. See Pike, Coomps and Hast- INGS, 125. Hawk, P. B. See Fisupack, Situ, * Bereemm, LIcCHTENTHAELER, REH- Fuss and Hawk, 174. See FisHpack, SMmivru, GEIM, Rexruss and Hawk, 222. See Minter, FowLer, BeRGEIM, Reuruss and Hawk, 254. See Smiru, FisHpack, BERGEIM, Reurvss and Hawk, 204. Hearing, on the effect of antipyretics on, 148. Henperson, Y. and H. W. Haaearp. The COs: dissociation curve as the complete expression of the acid base equilibrium of the blood, 117. HILpEBRANDT, F.M. See Murtin and HILDEBRANDT, 531. Hooxer, D. R. Physiological effects of air concussion, 121. Hoorrr, C. W. See Fostrar, Hoorer and WHIPPLE, 129. Hoskins, R. G. American military hospital dietaries, 578. Hosmer, H. R. See Crite and Hos- MER, 124. Howse, P. E., C. C. Mason and 8. C. Dinsmore. Variations in strength and in the consumption of food by recruits and seasoned troops, 557. BER- 592 Hydrogen ion concentration in sweat and urine after exercise and heat, changes in, 127. Hyman, L. H. Physiological studies on Planaria. I. Oxygen consump- tion in relation to feeding and starvation, 377. Hypophysis and thyroid, functional correlation of, 55. —, relation of, to glycogenolysis, 248. [NDUSTRIAL physiology, the work of the United States Public Health service in, 132. Infections of pharynx and tonsils, an experimental study of a _ possible mechanism for, 144. Intra-cellular acidity in Valonia, 147. Intravenous injection of fluids, a de- vice for, 122. Isaacs, S. See Macut, GREENBERG and Isaacs, 148. Ivy, A. C. A comparative study of the relation of the cerebral cortex to labyrinthine nystagmus, 141. Studies on experimental gastric and duodenal ulcer, 143. Studies on the secretion of the pyloric end of the stomach, 142. JORDAN, S. See Ryan, Jorpan and Yates, 133. KETON, R. W. and F. C. Brcut. The relation of hypophysis to glycogenolysis, 248. Kenpatu, E. C. Physiological action of the thyroid hormone, 136. Kidney, studies on nervous control of, 302, 317, 326, 335, 339. Kinney, M. See Sronanp and Kin- NEY, 135. Kocu, M. L. and O. Rippie. Further studies on the chemical composition of the brain of normal and ataxie (?) pigeons, 138. INDEX Kouus, A. C. See Marsa and Ko.ts, 302, 317, 326, 335, 339. Krusz, T. K. The pharmacology of acacia, 137. LANG, R.S. See Frasrr, Lane and Macteop, 126. Larson, C. N. A new type of re- breather. Demonstration, 131. Larson, J. A. On the functional cor- relation of the hypophysis and the thyroid, 55. Ler, F. 8. The work of the United States Public Health Service in in- dustrial physiology, 132. Lewis, W. H. The behavior of the centriole and the centrosphere in the degenerating fibroblasts of tissue cultures, 123. LICHTENTHAELER, R. A. See Fisu- BACK, SmiTH, BEeRGEIM, LICcHTEN- THAELER, ReuFuss and Hawk, 174. LomBarD, W. P. and O. M. Cops. Effect of posture on the length of the systole of the human heart, 140. Effect of pulse rate on the length of the systoles and dias- toles of the normal human heart in the standing position, 139. Lutz, B. R. Variations in alveolar air at low pressures, 119. McCLENDON, J. F. and W.. CG: Coin. The antiscorbutic proper- ties of green malt, 145. ——and F. A. Cotuarz. The electric conductivity and polarization of skeletal muscle, 146. Macut, D. I1., J. P. GRrENBERG and S. Isaacs. On the effect of antipy- retics on the hearing, 148. —— and 8S. Matsumoto. Action of corpeus luteum extracts on the move- ments of isolated genito-urinary organs, 149. Macteop, J. J. R. See Fraser, LANG and Macurop, 126. INDEX Mann, F. C. The treatment of the condition of low blood pressure which follows the exposure of the abdomi- nal viscera, 137. Marinus, C. J. The effect of feeding pars tuberalis and pars anterior proprior of bovine pituitary glands upon the early development of the white rat, 238. MaRsHALL, JR., E. K. and A. C. Kotts. Studies on the nervous control of the kidney in relation to diuresis and urinary secretion: I. The effect of unilateral excision of the adrenal, section of the splanch- nic nerve and section of the renal nerves on the secretion of the kidney, 302. II. A comparison of the changes caused by unilateral splanch- notomy with those caused by uni- lateral compression of the renal artery, 317. III. The effect of nicotine on the secretion of the two kidneys after unilateral section of the splanchnic nerve, 326. IV. Unilateral ligation of one branch of one renal artery and unilateral splanchnotomy, 335. VY. Chloride and sulphate diuresis after unilateral splanchnotomy, 339. Mason, C. C. See Howr, Mason and Dinsmore, 557. Matsumoto, S. See Macut and Mar- sumorTo, 149. Meats, gastric response to, 174, 204, 222. Metrzer, S. J. See GiTHens and Metrzer, 120. Menpet, L. B. See OssporNE and MENDEL, 138. Metabolism, respiratory, in Planaria, 420. Mitier, R. J., H. L. Fowter, O. Berceim, M. E. Reuruss and P. B. Hawk. The gastric response to foods. VI. Digestion in the normal 593 human stomach of eggs prepared in different ways, 254. Mour’s specific gravity balance for small quantities of liquids, a new form of, 123. Moupp, 8. and S. B. Grant. An ex- perimental study of a possible mech- anism for the excitation of infections of the pharynx and tonsils, 144. Morin, J. R.and F.M. Hitpesranpr. Average food consumption in the training camps of the United States Army, 531. Muscular strength and food consump- tion in army, 557. Myers, C. N. See VorarTnin and Myers, 124. NERVE, quantitative study of effect of salts on, 497. Nicotine, effect of, on secretion of the two kidneys, after unilateral section of the splanchnic nerve, 326. (CULAR and equilibrium disturb- ances following unilateral re- moval of otic labyrinth, compensa- tion of, 130. OssorNnE, T. B. and L. B. MENDEL. The nutritive value of yeast protein. 138. Oxygen consumption in relation to feeding and starvation in Planaria, 377. —, lack of, during starvation in Pla- naria, 403. PATTERSON, T. L. Postural ac- tivity of the empty stomach, 147, Pike, F. H., H. C. Coomss and A. B. Hastines. The dependence of re- spiratory activity upon conditions in the central mechanism, 125. Pituitary feeding, effect of, on growth, 238. Planaria, physiological studies on, 377. ——, respiratory metabolism in, 420. THE AMERICAN JOURNAL OF PHYSIOLOGY, VOL. 49, No. 4 594 Pianaria, susceptibility to lack of oxy- gen during starvation in, 403. Potassium salts, quantitative study of effects of, on nerve, 497. Pratt, F. H. and J. P. EISENBERGER. The quantal phenomena in muscle: Methods, with further evidence of the all-or-none principle for the skeletal fiber, 1. Prescott, 8S. C. Dried vegetables for army use, 573. Prince, A. L. On the compensation of ocular and equilibrium disturbances which follow unilateral removal of the otic labyrinth. Demonstration, 130. Proceedings of American Physiological Society, 117. Pulse rate, effect of, on length of sys- toles and diastoles of the normal human heart in the standing position, 139. (QQUANTAL phenomena in sartorius of Rana pipiens, 1. RANA pipiens, quantal phenomena in sartorius of, 1. Ration, scientifically balanced, in army camps, the practicability of feeding, 520: Rebreather, a new type of, 131. REDFIELD, A. C. On the relation be- tween the velocity of Beta rays from radium and their physiological ef- fect, 127. Reuruss, M.E. See FisHpack, SMITH, BrercreIM, LICHTENTHAELER, REH- Fuss and Hawk, 174. See Fisupack, SmiruH, BERGEIM, Reuruss and Hawk, 222. See Mitier, Fow ter, GEIM, ReuFuss and Hawk, 254. See SmitH, FIsHBack, GEIM, Reuruss and Hawk, 204. Renal function, relation of renal nerves to, 302, 317, 326, 335, 339. —— nerves, relation of, to renal func- tion, 302, 317, 326, 335, 339. BeEr- BER- INDEX Respiration volume and oxygen con- sumption, variations in, during re- duction of oxygen tension, 119. Respiratory activity, dependence of, on conditions in central mechanism, 125. —— metabolism in Planaria, 420. Rhythm in industry, 132. RippLe, O. See Kocu and Rrippiz, 138. Rogers, F. T. Studies on the brain stem. I. Regulation of body tem- perature in the pigeon and its rela- tion to certain cerebral lesions, 271. Rubidium salts, quantitative study of effect of, on nerve, 497. Ryan, A. H. and P. S. FLoReENcE. Rhythm in industry, 132. ——, S. Jorpan and A. B. Yartss. Muscular tonus in relation to fatigue, 133. GATANI, Y. Experimental studies of the ureter, 474. Secretine and antineuritic vitamine, influence of, on pancreatic secretion and bile flow, 124. Surptey, P. G. The physiological significance of the reaction of tissue cells to vital benzidene dyes, 284. Shock, circulation in, after abdominal injuries, 90. —— due to mechanical limitation of blood flow, 151. ——., secondary traumatic 90, 151, 345. Skeletal muscle, the electric con- ductivity and polarization of, 146. Skull, indirect concussion of, phe- nomena following, 120. Smiru, C. A., H. R. Fisupack, O. Brr- cEIM, M. E. Reuruss and P. B. Hawk. Gastric response to foods. IV. The response of the stomach to pork and pork products, 204. See FisHpack, SMITH, BERGEIM, Renruss and LicHTENTHAELER, Hawk, 174. See FisHpack, SMitH, BERGEIM, Reuruss and Hawk, 222. INDEX Sodium salts, effect of, on motor nerve, quantitative study of, 497. Starvation, oxygen consumption in, 377. Stewart, G. N. The electrical con- ductivity method of determining the relative volume of corpuscles and plasma (or serum) in blood, 233. Srotanp, O. O. and M. Kinney. Ef- fects of external temperature upon the toxicity of the thyroid, 135. Stomach, empty, postural activity of, 147. ——, studies on the secretion of the pyloric end of, 142. Surface tension measurement of liq- ulds, apparatus for, 123. Systole of the human heart, effect of posture on length of, 140. "TALBERT, G. A. Changes in hy- drogen ion concentration in the sweat and urine following exercise and heat, 127. Thyroid, effects of external tempera- ture upon the toxicity of, 135. 595 Thyroid, functional correlation of hypophysis and, 55. —— hormone, physiological action of the, 136. Tissue cells, reaction of, to vital benzi- dene dyes, 284. UNITED States Army, average food consumption in training camps in, 531 Ureter, experimental studies of, 474. VEGETABLES, dried, for army use, 572. VorctTuin, C. and C. N. Mymrs. A comparison of the influence of secre- tine and the antineutritic vitamine on pancreatic secretion and bile flow, 124. VW HIPPLE, G. H. See Foster, Hooprr and Wurppte, 129. YATES, A. B. See Ryan, Jorpan and YarTss, 133. Yeast protein, nutritive value of, 188. J ; i . i | \ ~~ | Sy oO 7 4 ot i 25 NG SECT. MAR 4 x 1966 e Americen Journal of Physiology A5 v.49 cop.2 Biological & Medical Serials PLEASE DO NOT REMOVE CARDS OR SLIPS FROM THIS POCKET ee UNIVERSITY OF TORONTO LIBRARY STORAGE PTh 5) eer a Sa SSS Rees ee Sones Soa eee S = : Se eas Se, ¢ Un bets ite 6 i ; peas hd Toe es ay Si 4 ay SS, hae s = esF See Wee sa) pk es +i; SF +n or, = < Se Sagt NS er = os Stem Rares — sees ie ame Tan te Diet Ace me Ses 7 ve Hi ada Olas: a aa bat ARIEL Bath) “it: Ait \45 aay a iy Nes y, ty ia Mt WCU Oe Abe ke RRsat fy SRE wee he Su x >