546 Journal of Agricultural Research vol. vi, xo. 14 



than passing importance. It denotes, first, that creatin is readily con- 

 verted into creatinin in pure solution, and, second, that in autolyzing 

 muscular tissue the rate of reaction is very greatly accelerated, but that 

 the total extent of the change is the same in either case. The more rapid 

 change of creatin into creatinin in the autolyzing tissue may safely be 

 assumed to be due, in large part, at least, to enzym action. This con- 

 forms to our idea as to the catalytic nature of enzyms. The gradually 

 reduced rate of change of creatin to creatinin during autolysis is in con- 

 formity with the law of mass action. These observations are of more 

 interest as regards the chemical relationship of the two substances than 

 on account of their physiological relationship, since in the animal body 

 any change of creatin to creatinin is accompanied with the rapid removal 

 of the creatinin, so that, so far as this factor is concerned, the change 

 always takes place at its maximum velocity. The clear establishment 

 of the fact that muscular tissue has the power in a marked degree of con- 

 verting creatin into creatinin must be regarded as having an important 

 bearing upon the formation of creatinin in the body. Without going 

 into a discussion of other investigations bearing upon this subject, it may 

 be said that there is much evidence in support of the theory that muscle 

 creatin is the source of urinary creatinin, with a creatin-creatinin-free 

 diet, and considerable evidence to the effect that in part, at least, the 

 transformation of creatin into creatinin takes place in the muscular 

 tissue. 



SUMMARY 



The results of the investigations reported in this paper concerning the 

 effects of autolysis upon the creatin and creatinin content of muscular 

 tissue of the ox may be summarized as follows : 



(1) Muscular tissue has in a marked degree the property of converting 

 creatin into creatinin. 



(2) In the course of autolysis an equilibrium is finally established 

 between creatin and creatinin. 



(3) Muscular tissue appears to have in an appreciable degree the 

 ability both to produce and to destroy creatinin. 



LITERATURE CITED 



(1) Emmett, A. D., and Grindley, H. S. 



1907. Chemistry of flesh. (Sixth paper.) Further studies on the application 

 of Folin's creatin and creatinin method to meats and meat extracts. 

 In Jour. Biol. Chem., v. 3, no. 6, p. 491-516. 



(2) Folin, Otto. 



1914. On the determination of creatinine and creatine in blood, milk, and 

 tissues. In Jour. Biol. Chem., v. 17, no. 4, p. 475-481. 



(3) Gottlieb, R., and Stangassinger, R. 



1907. tjber das Verhalten des Kreatins bei der Autolyse. In Ztschr. Physiol. 

 Chem., Bd. 52, Heft 1/2, s. 1-41. 



