HEMOLYSIS BY VENOMS 199 



the reptiles from their blood, which contains almost identical 

 amboceptors, differing chiefly in that they can combine only 

 with the complement contained in snake blood, while the ambo- 

 ceptors of venom can combine with the complement of nearly 

 all sorts of blood. Venoms from cobra, rattlesnake, moccasin, 

 and copperhead possess in each variety intermediary bodies 

 (amboceptors) that seem to be identical in nature, although they 

 may vary in quantity. This explains the rather remarkable 

 fact that serum of animals immunized against cobra poison, 

 generally called antivenin, will neutralize the hemolytic and 

 many of the other properties of the venom of rattlesnake, 

 copperhead, and moccasin. Antivenin acts as an anti-interme- 

 diary body, and by occupying a haptophore group of the ambo- 

 ceptor, prevents its completing the union of complement and 

 cell. In order of decreasing hemolytic power for mammalian 

 corpuscles come venoms from cobra, water moccasin, copper- 

 head, and rattlesnake. These venoms are also agglutinative 

 for all corpuscles tried, and agglutination will occur at C. 

 Exposure for thirty minutes at 75-80 C. destroys the agglu- 

 tinating property. In general, the hemolytic power of the 

 venoms for different sorts of corpuscles varies in inverse pro- 

 portion to its agglutinative power. The hemolytic intermediary 

 bodies are remarkably resistant to heat, suffering but slight loss 

 of power at 100 C. Red corpuscles of the frog are not hemo- 

 lized by venom, and those of necturus (mud puppy), but slightly, 

 agreeing with the known resistance of cold-blooded animals to 

 snake-bites. 



The highly hemolytic cobra venom can combine with comple- 

 ments contained within the red corpuscles, endocomplement, and 

 so produce hemolysis in the absence of serum complement. 

 Kyes has shown that lecithin may be the constituent of red cor- 

 puscles that acts as the complement. 



Eel serum is remarkably hemolytic, so much so that a quan- 

 tity of 0.1 c.c. per kilogram of body weight will kill a rabbit 

 or guinea-pig in three minutes when injected intravenously. 

 Heating at 54 C. for fifteen minutes destroys the hemolytic 

 action, and, unlike ordinary serum hemolysins the addition of 

 complement does not restore its activity. Animals can be 

 immunized against this serum. Introduced into the stomach in 

 ordinary quantities eel serum is not toxic. It can be dried and 

 redissolved without losing its activity, but acids and alkalies 

 readily destroy it. Mosso, who first discovered the toxicity of 

 eel serum, called the unknown active principle ichthyotoxin 

 (see preceding chapter). 



