B.—Cytolytic Action.
Simon Flexner and Noguchi[57] have observed that the venoms of Naja, Ancistrodon, Crotalus, Vipera russellii, and Lachesis flavoviridis, contain substances which possess the property of dissolving a large number of the cells of warm-blooded and cold-blooded animals, and that these cytolysins are very markedly resistant to high temperatures.
They employed for their experiments 5 per cent. emulsions of organs, spermatozoids, or ova in physiological saline solution. The solution of venom at a strength of 1 per cent. was kept in contact with the different kinds of cells for three hours at a temperature of 0° C.; the liquid was then centrifuged and examined with the naked eye and under the microscope.
The venoms experimented upon dissolved more or less rapidly the parenchymatous cells of the liver, kidney and testicle of the dog, guinea-pig, rabbit, rat and sheep. The most active venoms in this respect were those of Vipera russellii, Ancistrodon and the Cobra; the venom of Crotalus was the least active.
With regard to the nerve-cells, spermatozoids and ova of cold-blooded animals (frogs, fish, arthropods, worms, and echinoderms) Cobra-venom proved to be the most active; then that of Ancistrodon, and lastly that of Crotalus.
These cytolysins are not destroyed by heating for thirty minutes at 85° C. in a damp medium, nor by dry heating for fifty minutes at 100° C.