Creatinine in Muscle. 



15 



they then decline upon these diets. Milk food speedily brings 

 restoration of growth; and it has been shown that the "essential" 

 accessory factor responsible for this effect is a component of the 

 cream which is present in butter. 1 Further experiments now indi- 

 cate that the butter-fat separated by centrifugal methods from 

 unsalted butter contains the substance which averts the cessation 

 of growth and possible nutritive decline noted when lard is used 

 instead of milk-fat. 



Butter-fat thus prepared is free from nitrogen, phosphorus 

 and ash-yielding constituents. The growth-promoting substance 

 therefore is not a phosphatide (lecithin) or an inorganic compound. 



8 (825) 



The presence of creatinine in muscle. 



(Preliminary paper.) 



By Morris S. Fine and Victor C. Myers. 



[From the Laboratory of Pathological Chemistry, New York Post- 

 Graduate Medical School and Hospital.] 



The presence of creatinine in muscle has, in general, been 

 denied by those who have undertaken a study of this question. 

 In earlier communications 2 upon various phases of the creatine- 

 creatinine problem, evidence has been presented which is strongly 

 in harmony with the metabolic relationship of these two sub- 

 stances. Since creatinine is so rapidly eliminated from the body, 

 its presence in the muscle tissue would not be expected in large 

 quantity. On the other hand, if creatinine originates from 

 creatine, this transformation might be expected to take place in 

 the muscle tissue, and on this account it would seem that, with 

 sufficiently delicate and reliable methods, it ought to be possible 



1 Osborne and Mendel, "The Relation of Growth to the Chemical Constituents 

 of the Diet," Journ. of Biol. Chem., XV, pp. 311-326, 1913; also McCollum and 

 Davis, "The Necessity of Certain Lipins in the Diet During Growth," Journ. of 

 Biol. Chem., XV, pp. 167-175, 1913. 



2 See Myers and Fine, Proc. Soc. Exp. Biol, and Med., 1912-13, X, pp. 10, 

 12 and 168; also Jour. Biol. Chem., 1913, XIV, p. 9; XV, pp. 283 and 305; XVI, 

 p. 169. 



