Scientific Proceedings. 



i i 



salt and prevents its fatal accumulation in the blood. On the 

 basis of this assumption a series of experiments were carried out 

 in which the anesthetic effects of subcutaneous injections of mag- 

 nesium sulphate were studied in nephrectomized rabbits. The re- 

 sults briefly stated were as follows : 



A dose of 0.8 gram of the salt per kilo of rabbit is sufficient to 

 put the animal within a short time into deep anesthesia. This is 

 less than half the dose that is required to anesthetize a normal 

 rabbit. Furthermore, the nephrectomized rabbits thus anesthetized 

 remained in a more or less comatose, paralyzed state until death, 

 which did not occur earlier than in the control nephrectomized 

 animal ; in other words the animals remained in a state of anes- 

 thesia lasting sometimes two days and longer. Frequently the 

 animals recovered slightly some hours after the injection, to sink 

 soon again, however, into a deep stupor which lasted until death. 

 The described effect was the same whether the above mentioned 

 quantity of salt was given in one dose or was administered in 

 fractions. 



These facts demonstrate that elimination of the injected magne- 

 sium salt occurs mainly through the kidneys and that the elimination 

 begins pretty soon after the injection. Hence when the kidneys 

 are absent and practically no elimination takes place a smaller dose 

 is sufficient to bring on the anesthesia, and it makes no difference 

 whether the quantity is given at once or in small doses at varying 

 intervals. Furthermore, the anesthesia is long lasting and con- 

 tinuous, as the salt cannot leave the body. 



These results are especially interesting as they are in sharp 

 contrast to the behavior of strychnin in nephrectomized animals. 

 According to the experiments of Salant and Meltzer the toxic and 

 the fatal doses of strychnin are the same for nephrectomized 

 rabbits as for normal ones. Furthermore, when strychnin is 

 given in subminimum doses nephrectomized animals can stand as 

 much as three times the lethal dose. Finally the animal either 

 dies from the effects of strychnin or recovers completely ; a con- 

 tinuous long lasting convulsive state never occurs after any dose of 

 strychnin in nephrectomized animals. 



