VENOM HAEMOLYSIS AND VENOM AGGLUTINATION 193 



no longer attacked and rendered lytic by the otherwise active native venom 

 of the lecithid. 



At the same time von Dungern and Coca show that a subminimal haemo- 

 lytic dose of cobra lecithid becomes a complete haemolyzing dose if enough 

 of lecithin be added to the mixture, showing that there is still present in the 

 so-called pure lecithid enough lecithin-splitting venom component. On the 

 other hand, the antihaemolytic powers of the heated normal and immune 

 rabbit serums do not differ if they are tested against the lecithid which had 

 been heated to 100 C. for 3 hours, because here the specific anti-body is not 

 concerned in the reaction. In the case of the heated normal serum the 

 lecithin remains unattacked by the lecithid without the adhering native 

 venom and there will be no more haemolysis than in the case of the fresh serum. 



Von Dungern and Coca do not consider it necessary to assume that cobra 

 lecithid is a chemical compound of venom and lecithin, but entertain the 

 view that the hsemolytic substance is only a split product of lecithin and is 

 contaminated with a minute quantity of native venom component, the latter 

 playing but little part in the hasmolytic activity of the whole lecithid. 



From various preparations of ovolecithin they were able to isolate a highly 

 haemolytic substance with all the physical and biological characteristics of 

 cobra lecithid, except that it did not show evidence of the adherence of native 

 cobra venom, and hence no increase in its lytic power by lecithin addition and 

 no antilysin formation in the animal body. Its haemolytic activity was 

 about half that of cobra lecithid. 



In a subsequent paper l von Dungern and Coca attempted to solve the 

 mechanism of venom haemolysis induced by adding oleic acid or sodium oleate 

 in subminimal inherent haemolytic quantities. As already stated, Noguchi, 

 among many other acrylic acids and soaps, found these two chemicals espe- 

 cially suitable for rendering the blood corpuscles haemolyzable by venom. 



Von Dungern and Coca treated the ox corpuscles with cobra-venom solu- 

 tion for i hour (20 c.c. 5 per cent corpuscular suspension and 2 c.c. i per cent 

 cobra- venom solution), and then, after separation from the venom, their sus- 

 ceptibility to the haemolytic action of oleic acid and sodium oleate was tested. 

 The result shows that the degree of haemolysis is the same whether the cor- 

 puscles have been venomized or not. Thus they could find no comparison 

 between the haemolytic serum complement and these oleic compounds. Then 

 they tried to ascertain if cobra venom can act directly on these chemicals and 

 render them more active, but this was found not to be the case. On the 

 contrary, oleate soap, if allowed to act long, rather diminished than increased 

 the action of cobra venom when there was no blood or lecithin in the mixture. 

 However, if the soap, venom, and lecithin are allowed to remain in contact 

 for a much longer period, the haemolytic activity of such mixture is rather 

 greater than that of a mixture in which soap is added at the same time as or 

 just before the addition of blood. Oleic acid always exerts an accelerating 



Von Dungern and Coca. Ueber Hamolyse durch Kombination von Oelsaure oder dlsaures Natrium 

 und Kobragift. Munch, med. Woch., 1908, LV, 105. 



