462 



VICTOR C. MYERS 



Normally muscle tissue contains rather more creatinin than the blood, 

 but in cases of marked nitrogen retention the blood may slightly exceed 

 that of the muscle (Myers and Fine (c)). The uric acid of the muscle 

 scarcely keeps pace with the rise in the blood uric acid which occurs in 

 some cases of advanced nephritis. The figures for the non-protein nitrogen 

 of muscle are much higher than those of the blood, owing chiefly to the 

 much larger amounts of creatin and amino-acid nitrogen present in muscle 

 than in blood. 



The table below compiled from observations of Mosenthal, Clausen and 

 Hiller, and Myers and Fine (b) gives an idea of the distribution of the 

 various non-protein nitrogenous constituents in the muscle tissue of 

 normal individuals and those suffering from severe nephritis. 



CONTENT OF NITROGENEOUS CONSTITUENTS IN HUMAN MUSCLE 



It is very difficult to completely free muscle tissue from adherent fat. 

 Figures as low as 0.6 per cent have been obtained in lean oxen and as high 

 as 9 per cent in fattened pigs. Less is known concerning the cholesterol 

 and phosphatids of the muscle, although the latter are present in much 

 higher concentration, especially in heart muscle. 



One may obtain an idea of the inorganic constituents of muscle from 

 the following table taken from Katz ( b ) . Of the different constituents tabu- 

 lated potassium and phosphorus are present in by far the largest amounts. 



MINERAL CONTENT OF THE MUSCLE OF MAMMALS 



In striated muscle the phosphorus is present largely in inorganic form, 

 but in heart muscle organic phosphorus may constitute more than half 

 of the phosphorus present. In the voluntary muscle of the rabbit, which 



