OTHER REACTIONS igj 



The Much-Holzmann Cobra Venom Reaction 



It has long been known that cobra venom haemo- 

 lyzes red blood corpuscles, and that certain cor- 

 puscles, such as those of man, dog, pig, horse, 

 rabbit, and guinea-pig hsemolyze directly on mixing 

 them with cobra venom, while others require the 

 intervention of an activating substance. To the 

 latter class belong the blood corpuscles of ox, 

 sheep, and goat. As already pointed out in dis- 

 cussing snake venoms, the activating substance is 

 present in blood serum; it is also present in com- 

 mercial lecithin. Haemolysis of either group of 

 blood corpuscles can be inhibited by means of 

 cholesterin, though just how this substance acts is 

 not clear. Much and Holzmann showed that the 

 blood serum of patients suffering from various 

 mental disorders, especially dementia praecox, and 

 manic-depressive insanity frequently inhibits hae- 

 molysis of human red blood corpuscles, and they 

 suggested that the reaction could be used for 

 diagnostic purposes. While it appears to be true 

 that the psychoses yield the largest proportion of 

 positive reactions, the value of the reaction for 

 diagnostic purposes is practically nil. At the same 

 time it is interesting to note that diseases of the 

 nervous system accompanied by demonstrable 

 lesions of the nerve tissue give the same reaction as 

 psychoses in which such lesions have not yet been 



