INFLUENCE OF HELODERMA VENOM UPON BLOOD-PRESSURE, DIURESIS, 

 PERITONEAL TRANSUDATE, AND INTESTINAL FLUID. 



By Mover S. Fleisher. 



Van Denburgh and Wight,* studying some of the physiological actions of 

 the venom of Heloderma suspectum, came to the conclusion that the lethal effect 

 of the venom was due to its influence on respiration. The animals injected 

 with venom died as a result of respiratory failure ; at the same time the blood- 

 pressure was lowered. In order to investigate further the influence of the 

 venom on blood-pressure we injected into rabbits large quantities of 0.85 per 

 cent sodium-chloride solution in which venom had been dissolved. We were 

 thus also able to study the effect of venom on the secretion of urine and the 

 transudation of fluid into the peritoneal cavity or into the intestines, as well as 

 the relation existing between the blood-pressure and the secretion of urine. 



The 0.85 per cent sodium-chloride solution was allowed to flow into the 

 jugular vein of the rabbit at the rate of 4 c.c. of fluid per minute. By means of 

 a hot-water bath the infused fluid was maintained at a temperature of 39 C. 

 Quantities of fluid varying between 600 and 700 c.c. were infused into the 

 rabbits. 



EXPERIMENTS WITH NON-NEPHRECTOMIZED RABBITS. 



In a first series of experiments, rabbits with intact kidneys were infused 

 with the sodium-chloride solution, to which venom had been added in the 

 proportion of 20 or 30 mg. to every 800 c.c. of the sodium-chloride solution. 

 Quantities of urine secreted during the inflow of every 50 or 100 c.c. of the 

 NaCl solution were noted. At the end of the experiment, after the inflow of 

 fluid had been stopped, the animal was killed and the quantity of fluid in the 

 peritoneal cavity and small intestines was measured. By means of a mercury 

 manometer connected with the carotid artery of the rabbit, the arterial blood- 

 pressure was measured during the time of the infusion. 



Immediately after the infusion of the venom-sodium-chloride solution 

 was started the blood-pressure of the rabbit became rapidly lower; after 20 to 

 50 c.c. had been infused, a fall of 10 to 40 mm. of mercury could be observed; in 

 our 5 cases the average fall of blood-pressure was 24 mm. After the first rapid 

 fall the blood-pressure remained either approximately stationary or gradually 

 decreased slightly. After 600 or 700 c.c. of the venom-sodium-chloride mixture 

 had been infused the arterial blood-pressure was usually between 80 and 60 

 mm. of mercury (figs. 15 and 16). In only one of these experiments, toward 

 the end of the infusion, the blood-pressure fell below 50 mm. In this experi- 

 ment, the only one in which 30 mg. of venom was used, the animal died as a 



*Van Denburgh and Wight, Trans. Amer. Phil. Soc, 1S98, xix, 199. 



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