RATE OF PENETRATION OF PHOSPHATE INTO MUSCLE CELLS 



447 



The amount of ^ap which penetrates into the muscle tissue in the 

 course of the first 3 minutes is much smaller than that of ^^Na ; this 

 phenomenon is due to a slower x)enetration of the phosphate ions through 

 the capillary wall. After the lapse of 1 hour, a slightly greater percentage 



Accumulohon 

 tn rne eeiis 



Accumulation in the interspoces 



10 20 50 uo 50 



50 70 90 90 10O 



time in hours 



Fig. 1. Accumulation of ^^P in the cells of muscle tissue. 



of the plasma ^sp is found in the muscle tissue than of the plasma -^Na, 

 the difference increasing with time. This phenomenon is due to a suc- 

 cessive penetration of ^ap into the muscle cells. The amount migrated 

 into the cells is obtained by subtracting the sodium space from the 

 apparent phosphorus space. After 10 hours we find, as seen in Table 1 

 and Fig. 1, that the amount of 32p which diffused into the cells of 1 gm 

 gastrocnemius makes up 14 per cent of the ^-P content of 1 gm plasma 

 or about 100 per cent of the ^^p present in the interspaces of 1 gm. 



