CHAPTER XVIII. 



HISTOLOGICAL CHANGES PRODUCED BY SNAKE VENOM 

 ON VARIOUS ORGANS AND TISSUES. 



Before presenting the facts derived from the elaborate and extensive studies 

 of various investigators concerning the histological alterations produced by 

 snake venom, a general review of the nature of these changes may be per- 

 mitted at this place. 



As we shall presently see, the histological changes, which were demon- 

 strable with the practicable methods of our past and present histological 

 status, fall into two great groups. The first group is the fatty degeneration of 

 the protoplasma of the diverse kinds of cells, and the other comprises the 

 changes designated necrosis. The question quickly arises whether both 

 are the action of the same principles or the actions of specific agents for each 

 group of alteration. In view of the recent development in the biochemical 

 investigations of the active principles contained in snake venom and other 

 similar cellular toxins, it appears that the latter hypothesis conforms to the 

 observed facts. The lipolytic properties of snake venom — especially the libera- 

 tion of fatty acids from phosphorized and non-phosphorized fats by certain 

 ferment-hke principles of venom — render it probable that fatty degeneration 

 is the result of the cytolysis of such agents. It is partly due to the Ehrlich- 

 Kyes phenomenon (or formation of lecithids and hberation of free fatty acids) 

 and to the Neuberg-Rosenberg phenomenon (or the splitting of neutral fats) , 

 both being liable to take place in media as rich in lecithin and fats as the cell 

 protoplasma. Considering the potency which a minute quantity of venom 

 circulating in the venomized body possesses, it is again reasonable that in the 

 production of fatty degeneration lecithin-splitting plays the foremost part. 



The necrotic changes I consider due to the specific phenomena peculiar to 

 each group of somatic as well as nervous tissues, and brought about by the 

 action of specific cytolysins in the sense of Flexner and Noguchi, namely: 

 there exists between the cells and the active principles a special affinity, if not 

 specific. The relation between fatty degeneration and the necrotic altera- 

 tions of these cells is not quite clear, inasmuch as various fatty and lipoid 

 substances display marked destructive effects on various cellular elements. 

 It may be true, at least in part, that the necrotic processes are caused second- 

 arily by the primary fatty degeneration. On the other hand, there are many 

 evidences that point in the opposite direction. Fatty degeneration may be 

 entirely absent from the cells showing marked disorganization of their con- 

 stituents. Equally we may assume that fatty degeneration may be produced 

 secondarily by the cessation of the normal oxidating function of the cells, 

 through specific toxins of venom. In deciding this point the results which I 



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