The pupils dilate and then become motionless. The temperature rises from 1° to 2° Centigrade. There is somnolence at this stage, with increased intestinal peristalsis. The pulse and respirations are quickened; later these with the temperature return to the normal, and the animal recovers. Large doses cause death with the heart in diastole and the intestines contracted.
Clonic spasms and stupor precede death.
The Extraction of putrefactive alkaloids from organic matters may be carried out by the process for alkaloid extraction ([vide p. 335 et seq.]).
Amongst the attempts made to distinguish the putrefactive from vegetable alkaloids by chemical reactions one method was based on the rapid reduction of potassium ferricyanide to the ferrocyanide. After converting the alkaloid to a sulphate, a solution of it is mixed with a drop of potassium ferricyanide and a drop of ferric chloride added: the deep blue colour of Prussian blue is produced if reduction to the ferrocyanide has taken place. However, certain vegetable alkaloids, viz. morphine, aconitine, eserine, and hyoscyamine act rapidly as reducing agents upon the ferricyanide. Emetine, igasurine, nicotine, colchicine act less rapidly. Brieger considers that when the reaction occurs with putrefactive alkaloids it is due to impurities present in them. Brouardel and Boutmy have suggested making use of the action of alkaloids upon photographic silver bromide paper as a means of distinction. The paper is written upon with a solution of the alkaloid and kept light free for half an hour; it is then fixed in a solution of sodium hyposulphite and washed in water. The putrefactive alkaloids are said to reduce and blacken the silver compound, while the vegetable alkaloids do not. Neither of these processes is to be relied upon for medico-legal purposes.
LEUCOMAINES OR
ANIMAL ALKALOIDS
Leucomaines or animal alkaloids are basic substances which originate from the metabolic processes taking place in the animal body. They closely resemble the vegetable alkaloids, and some are found in plants as well as animals. It is probable that some of them may have originated primarily from the putrefactive processes in the intestines and been absorbed into the system. The following is a list of the principal leucomaines resulting from the metabolism of the tissues of the animal body:
Adenin, C₅H₅N₅.—From thymus gland, from all tissues animal or vegetable which are rich in nucleinic acid—poisonous in large doses.
Sarkine or hypoxanthine, C₅H₄N₄O.—From urine and flesh—causes increased reflex excitability and convulsive seizures.
Guanine, C₅H₅N₅O.—From flesh and guano—it is inert.
Xanthine, C₅H₅N₄O₂.—From flesh and urine—acts as a muscle stimulant.