16 



CAFFEIN IN NEPHRECTOMIZED RABBITS. 



to resist putrefaction, its absorption from some part of the gastro- 

 intestinal tract is the only logical conclusion. 



SERIES VIII. Recovery of caffein in rabbits nephrectomized by lumbar incision and 5 or 

 6 hours later injected subcutaneously with 150 my per kilo. 



Although the existence of compensatory elimination by the stom- 

 ach and intestines in conditions of renal insufficiency is frequently 

 assumed by clinicians, this is still a matter of dispute among investi- 

 gators. The results of the experiments recorded in the present inves- 

 tigation are therefore of interest as bearing upon an important 

 problem in physiology, which may also be of value in human and 

 veterinary therapeutics. As shown in Bulletin 157, from 3.5 to 5 

 per cent of the caffein administered is eliminated into the lumen of 

 the gastrointestinal canal of normal rabbits at the end of from 22 to 

 24 hours and the same was found true in guinea pigs. After the 

 removal of the kidney the amounts of caffein recovered from the 

 contents of the stomach and intestines of rabbits varied between 7.7 

 and 11.78 per cent of the quantity administered, which is therefore 

 about twice as much as is eliminated in normal animals by this 

 channel, the increase being especially marked in the intestines, as 

 may be seen by referring to the protocols. Examination of the con- 

 tents of the gastrointestinal canal from one and one-half to four hours 

 after the administration of caffein revealed the presence of amounts 

 proportionaUy much larger, thus showing an increased rate of elimi- 

 nation by this channel at this period. This was also studied in normal 

 rabbits in the experiments of Series IX. 



ELIMINATION OP CAFFEIN IN RABBITS IN WHICH URINE WAS SCANTY OR ABSENT 



(SERIES IX). 



Rabbit 839 .Weight, 1,370 grams; laparotomized. 



July 18, 1912: The common bile duct was ligated and 48 hours later the subject was 

 given 150 mg per kilo caffein subcutaneously. Four hours later the subject was 

 chloroformed, and the following determinations made: Caffein recovered in urine, 

 5.15 per cent; in intestines, 8.75 per cent; in stomach, 2.50 per cent; total, 16.40 

 per cent. 



Rabbit 834- In early pregnancy; laparotomized; weight, 1,650 grams. 



July 18, 1912: 11.30, ligature around the upper part of the pylorus and the small 

 intestine, below the common bile duct, the bile duct also ligated, ethyl chlorid used, 



