610 MEDICAL JURISPRUDENCE
Fish in sprawn is likely to produce poisonous symptoms. Of all the varieties of
shell-fish, mussel is the chief, that gives rise to poisonous symptoms on account of a
powerful toxin, mytilotoxine, which develops chiefly in its liver. The characteristic
, symptoms are urticaria and difficulty of breathing. Death may occur from collapse
within two hours.
The symptoms of gastro-enteritis may occur from eating stale or decomposed oysters.
These are alkaloidal bodies produced by the action of saprophytic micro-organisms
upon nitrogenous materials, probably during the process of decomposition, They are
called cadaveric alkaloids, as they are generated in the dead tissues ; while alkaloids
secreted by the living cells during the metabolic processes are called leucomaines*
Ptomaines exist as methylamine in the gaseous form, as ethylamine in the liquid
form and as neurine in the solid form. They are unstable alkaline bases, forming salts
when acted upon by acids. v
These ptomaines resemble very closely vegetable alkaloids, such as veratrino, mor-
phine, codeine, etc.. inasmuch as they respond almost to the same chemical group
reagents and physiological tests. At present there is no special test by which a cada-
veric alkaloid can be distinguished from a vegetable alkaloid; however, no cadaveric
alkaloid will yield the same chemical reactions and will have the same physiological
results, if injected into the body of a healthy animal, as any of the vegetable alkaloids.
In suspected poisoning, when one of the rare vegetable alkaloids, which does not
ordinarily respond to chemical tests, has been detected in the body, the defence pleader
may set up a plea that the alkaloid was not a vegetable poison, but a ptomaine developed
in the body after death.
In this connection it is important to know that most of "the ptomaines that have
been discovered are non-poisonous except neurine and mydaleine, which are actively
poisonous and produce symptoms resembling those produced by atropine, muscarme,
aconitine, etc. It is said thai; neurine is not generated till the fifth or sixth day has
elapsed since death, and mydaleine not until the seventh day and that too in traces only,
It must, however, be remembered that these putrefactive bases, being volatile and soluble
in water, are not likely to be extracted with immiscible solvents from organic mixtures.
Bagchi22 states that in his laboratory necropsy materials from nearly one thousand cases
are analysed every year, but he has never been able to isolate such bases from the
viscera of highly decomposed bodies which are so common in India, especially during
the hot and rainy months of the year.
22. Ghosh and Bagchi, Organic and lexicological Chemistry, Ed, IV, $>. 432,