CTRCrLATIOX OF L'HOSI'lIORUS IX THK KK()(i 



395 



or less successful prevention of the decomposition of 1li(» creatinephos- 

 phoric acid prior to the removal of the inorganic phosphale of Uio muscle 

 1 issue. 



The resvills c^f an (experiment, in whicli the frog was kept at 2(f for 



Table 11. — Spjxific Activity of Phosphor is Fractions Extracted from the 

 Gastrocnemius of a Frog, 4 Hours after Injecting Labelled Sodixxm Phos- 

 phate INTO THE Ly.MPH SACK. TeMP. : 2° 



Fnictiou 



1' content 

 in mgm 



Aotivitj- ill per Per cent of tot^l 

 cent of tlie Stan- activity adminis- 

 dard preparation tered per mgm P 



Holative 

 specific 

 activity 



We denote as pyrophosphate + hexose P the inorganic phosphorus obtained after the hydrolysis of a 

 fraction for one hour at 100" in 1 X. HjSOj after tlie removal of the inorganic and creatine P. 



4 hours and then for 1 hour at 0°, is seen in Table 18. The muscles were 

 immersed in liquid air and treated with cold 5 per cent trichloracetic 

 acid. The extract was sucked through a glass filter into cooled Fiske's 

 leagent. These operations took 2 minutes. In this experiment, we tested 



Table 12. — Specific Activity of Phosphortts Frac- 

 tions Extracted from the Gastrocnemius 

 OF frogs. Temp.: 2° 



Time of the 

 experiment hours 



Fraction 



Specific activity 



4 

 4 

 4 

 4 

 3 

 3 



Inorganic P 

 Creatine P . 

 Inorganic P 

 Creatine P . 

 Inorganic P 

 Creatine P . 



100 



14.8 

 100 



21.4 

 100 

 8.8 



to what extent the inorganic P is precipitated by Fiske's reagent. 

 After precipitation of the "free" phosphate, 60 mgm sodium phosphate 

 were dissolved in the filtrate, the phosphate was then precipitated and 

 its activity tested. If the first precipitation was strictly quantitative, 

 this second precipitate should be inactive. The counter registered 228 

 counts while, in the case of the first precipitate. 2500 counts were regis- 



