BIOCHEMICAL STUDIES UPON THE VENOM OF 

 HELODERMA SUSPECTUM. 



By Carl h. Alsbebq. 



The most important study of the chemical nature of the venom of Helo- 

 derma was made by Santesson.* His conclusions were in the main that no 

 alkaloidal substances were present, but that the toxic principle was part nuclein 

 and part albmnose. He also discovered that boiling a solution of the venom, 

 even in the presence of acetic acid, did not materially injure its toxicity; and 

 that the toxic principle was precipitated but not coagulated by alcohol and 

 similar agents. The purpose of the present investigation was to endeavor to 

 isolate the toxic principle or, failing that, to extend the observations of San- 

 tesson. It was expected that these questions might be solved because more 

 material was available than Santesson had, and because in recent years, through 

 the work of Faust on cobraf and rattlesnaket venom, our knowledge of the 

 chemistry of venoms of reptiles has been greatly extended. It was hoped 

 that it might be possible to isolate the active principle of heloderma venom by 

 means devised by Faust. 



The first step in this investigation was to apply to the dried venom the 

 various methods used by Faust. To test the toxicity in the course of this chem- 

 ical work mice were invariably used and the solutions injected subcutaneously. 



Faust's copper method was first tried. 0.2 gm. of finely powdered venom 

 was suspended in 15 c.c. of water and allowed to extract for an hour. A small 

 portion remained undissolved. It was removed by filtration and thoroughly 

 washed with water on the filter. It was dissolved on the filter in 2 c.c. of 0.8 

 per cent sodium-chloride solution rendered weakly alkaline with sodium car- 

 bonate. 0.5 c.c. was injected into a white mouse of 20 gm. beneath the skin 

 of the abdomen. The following morning the mouse was found dead, lying flat 

 and relaxed on its abdomen, as though it had died of progressive paralysis with- 

 out convulsions. The experiment was repeated with the remainder of the 

 sodium-carbonate solution neutralized with a trace of hydrochloric acid. Neu- 

 tralization caused the solution to become opalescent; a slight excess of acid 

 caused a precipitate. The result of the injection, as was to be anticipated, was 

 entirely the same as with the unneutralized solution, for the amount of sodium 

 carbonate used was very slight, quite insufficient to produce serious effects by 

 itself, as control injections of pure sodium-carbonate solutions of the same 

 strength showed. 



•Santesson, C. G. Ueber das Giit von Heloderma suspectum Cope, einer giftigen Eideclise, Nordiskt Medioinisk 



Archiv., Festband Axel Key, 1897, Nr. 5. 

 IE. St. Faust. Ueber das Orphiotoxin aus dem Gifte der Ostindischen Brillenschlange {Naja tripudians), Archiv fiir 



experimentelle Pathologie und Pharmakologie, Bd. 56, S. 236 (1907). 

 JE. St. Faust. Ueber das Crotalotoxin aus dem Gifte der Nord-Amerilcamschen Klapperaclilange (Crolalus adaman- 



tens), ibid., Bd. 64, S. 214 (1911). 



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