Pyrimidin Bases

Of the Pyrimidin bases the di- and tri-amino derivatives are toxic, and these yield insoluble- compounds which may be deposited in the renal tubules.

Hexon Bases

Of the Hexon bases, Gerontin, C5H14N2, only is poisonous, 0.5 mg. killing 10 g. of frogs. It is an isomer of cadaverin which it resembles somewhat, and is occasionally observed in crystalline form in the cell nuclei of the liver and kidneys. It exerts a paralyzing action upon the nerve centres and heart ganglia leaving the muscles unaffected.

Protcimins And Histons

The Protcimins and Histons are primitive proteids yielding hexon bases on cleavage and exist in herring, sturgeon, shad, salmon, and in the substance of some of the bacteria. They are germicidal, and when in jected subcutaneously cause tissue necrosis at the point of injection, fall of blood temperature, decrease in the number of circulating leucocytes, delay in the coagulation of the blood and death from paralysis of respiration. In dogs death rapidly followed when the dose was 0.015 g. of culpein, and 0.02 g. of sturin per K.

Besides delaying the coagulation of the blood for many hours, these substances cause agglutination of the corpuscles as do albumose, ricin, venoms and agglutinating sera.

Histon is found in the thymus and thyroid glands and in dose of 0.1 g. in a rabbit caused irregular heart action, labored respiration, lachrymation, salivation, paralysis and death. That histon will neutralize bacterial toxins has been shown by Novy who found that its admixture with tetanus and diphtheria toxins rendered them harmless.

Creatinin Group

Of the Creatinin group, Xcintho-creatinin, C5H10N4O, alone has been shown to be distinctly poisonous. It is increased in muscular activity and when given to animals causes depression, somnolence, languor, frequent defecation and vomiting. The writer has been unable to find experimental evidence that the substances of this group are as poisonous as some writers state.