KYNURENIC ACID. 255 



does not give rise to kymirenic acid in metabolism, acting 

 precisely like the carbohydrates in this respect. In conditions 

 of ordinary nitrogenous equilibrium, or under the influence of 

 proteid-sparing foods, kynurenic acid excretion is greatly 

 diminished or absent. 



The observations suggest the presence of quinoline-like 

 radicals in the proteid molecule; the existence of a large 

 carbohydrate group is also confirmed. 



Uric acid and kynurenic acid may occur together in dog's 

 urine, as Solomin has found. Kynurenic acid is absent from 

 the urine of the cat during fasting and proteid feeding, and is 

 not found in the urine of the rabbit during inanition. 



