154 Society for Experimental Biology and Medicine. 



them with food masticated and well insalivated by other normal 

 dogs. 



4. The abolished gastric secretion is temporarily resumed by 

 peritoneal or intravenous injections of extracts made of salivary 

 glands of normal dogs. 



5. This temporary resumption takes place even if the stomach 

 be completely isolated from the central nervous system. 



These observations justify the conclusion that normal gastric 

 secretion depends upon the internal secretion of the salivary glands. 



107 (250) 



The influence of diuresis upon the toxic dose of magnesium 



salts. 



By S. J. MELTZER. 



[From the Rockefeller Institute for Medical Research^ 



In the communication on the effects of subcutaneous injec- 

 tions of magnesium salts, John Auer and I stated that a dose of 

 magnesium sulphate slightly larger than 1.75 gram per kilo is 

 surely fatal for the rabbit. Lucas and I showed later that in 

 nephrectomized animals the toxicity of the salts is greatly in- 

 creased. At the April meeting I conducted an experiment demon- 

 strating that in nephrectomized animals magnesium sulphate can 

 become toxic even when given by mouth. These lines of experi- 

 mentation have shown that the toxicity of magnesium salts depends 

 upon the normal activity of the kidneys. I wish now to report 

 the results of a series of experiments in which the effect of an 

 increased renal activity was studied. 



Briefly stated the results were as follows : A dose of 2 grams 

 of magnesium sulphate per kilo is absolutely fatal for the rabbit ; 

 the animal dies of respiratory paralysis in less than an hour. All 

 the animals recovered from the effects of such a dose, however, if 

 an intramuscular injection of diuretin was given soon after the 

 subcutaneous injection of the magnesium salt. Diuretin is theobro- 

 min and acts as a diuretic. The deeply narcotized animals usually 

 urinate about fifteen or twenty minutes after its injection ; by that 

 time, at least, the bladder can be felt to be full. The largest dose 



