15 WALTEK JONES 



Animal Species. Uricolytic Index. 



Opposum T9 



Sheep 80 



Horse 88 



Monkey . . . . : 89 



Goat 92 



Cow 93 



Guinea pig 94 



Rabbit 95 



Raccoon 95 



Rat 96 



Coyote 97 



Cat 97 



Dog 98 



Badger 98 



Pig 98 



Ape 



Man 



5. Xanthine oxidase, like uricase, is generally confined to the liver 

 (ox, pig, rabbit, guinea pig, opossum, man), but is not so widely dis- 

 tributed as uricase. Thus certain livers (rat and dog) are provided with 

 a ferment to destroy uric acid but with none to form it This is not an 

 uncommon circumstance. Rabbit's liver it able to oxidize hypoxanthine to 

 uric acid, but cannot form hypoxanthine from adenine. 



Perhaps the most active occurrence of xanthine oxidase is in human 

 liver, which accords with man's low" output of purine bases, the ratio of 

 purine bases to uric acid being thirty-five times greater in monkey's urine 

 than in human urine. 



The deficiency of xanthine oxidase in the organism of the monkey (cer- 

 copithecus) was noted by Hunter. In a haphazard quantity of urine 

 he found 



Uric acid 320 



Xanthine 950 



Hypoxanthine 360 



Guanine 000 



Adenine . . ; 000 







Even subcutaneously injected xanthine was recovered unchanged. (Hun- 

 ter and Givens (6).) 



Xanthine oxidase is not present in yeast where such a multitude of fer- 

 ments occur, nor is uric acid to be found in plants. 



6. Guanase is the most widely distributed of all the purine ferments. 

 With many animal species it is uniformly present in all of the principal 

 organs (rat, ox, guinea pig, rabbit). But pig's organs are peculiarly de- 

 ficient in the ferment, and the muscles of the animal frequently contain 

 deposits of guanine, due perhaps to "guanine gout." (Virchow (a) (6), 



866, 1866.) Pig's urine contains guanine and the purine bases are 

 always in excess of the uric acid. (Pecile ; Mendel and Lyman.) 



7. Adenase, on the contrary, is very rare, having a distribution that 

 is somewhat complementary to that of guanase. Its presence cannot be 

 shown in any of the principal organs of the rat, man or rabbit. As the two 



