'MH ADVENTURES IN RADIOISOTOPE RESEARCH 



is seen in Tables 2 and 3. More than 1/4 of the non-hydrolysable residue 

 of the organic acid soluble P fraction secured from the kidneys was, 

 for example, found to be renewed in the course of 215 min (see Table 2). 

 After the lapse of so long a time as 9 and 50 days (see Tables 4 and 5), 

 the muscle inorganic -f creatine P has only reached 40 and 88 per cent, 

 respectively, of the specific activity of the plasma inorganic P. After 

 the lapse of 50 days, the specific activity of the ester P of the muscles 

 was found to be 77 per cent of that of the plasma inorganic P. A detailed 

 investigation of the rate of renewal of the acid soluble P compounds 

 present in the muscles of the frog will be published shortly. 



B) Renewal of the acid soluble P compounds present in the corpuscles 

 1. Phosphorylation processes going on inside the corpuscles 



In our early investigations^^^ on the circulation of phosphorus, using 

 radioactive P as an indicator, we found that the organic acid soluble 

 P compounds of the red blood corpuscles are normally in a state of flux, 

 being continuously decomposed and resynthesized. Labelled phosphate 

 ions were found to penetrate into the corpuscles at a fairly slow rate 

 and to take part in very rapid phosphorylation processes inside the 

 corpuscles. Labelled hexosemonophosphate introduced into the plasma 

 was found not to penetrate at any significant rate into the corpuscles. 

 However, the labelled phosphate present in such hexosemonophosphate 

 molecules after being split off diffuses as inorganic phosphate into the 

 corpuscles and is incorporated inside the erythrocytes partly into hexose- 

 monophosphate molecules. Presumably, the P atoms of the plasma 

 diffuse exclusively or almost exclusively as phosphate ions into the 

 corpuscles. 



That phosphorus compounds, as hexosephosphoric acid, triosephos- 

 phoric acid, phosphopyruvic acid, phosphoglyceric acid, and so on, 

 take an important part in glycolytic processes going on in the corpuscles 

 was emphasised by v. Euler and Brandt^-^ and others. According to 

 the views of Meyerhof, Parnas, and others, in the course of the gly- 

 colytic cycle, hexosediphosphate, for example, is found to be formed 

 through the interaction of dextrose with adenosintriphosphate. Hexose- 

 diphosphate is maintained in enzymatic equilibrium with two molecules 



(^)L. Hahn and G. Hevesy, C. R. Lab. Carlsherg 22, 188 (1938). G. Hevesy 

 and A. H. W. Aten, Kgl. Danske Vidensk. Selskab, Biol. Medd. 14, 5 (1939). 



(2> H.V.EuLEB and K. M. Brandt, T. physiol. Chem. 240, 215 (1936). Comp. 

 also H. Lawaczeck, Biochem. Z. 145, 351 (1924); Negelein, Biochem. Z. 158, 

 121 (1925); M. Martland, Biochem. J. 19, 117 (1925); P. Rona and K. Iwasaki, 

 Biochem. Z. 184, 318 (1917); H. K. Barrenscheen and B. VAsArhelyi, Biochem. 

 Z. 230, 330 (1931); H. K. Barrenscheen and K. Braun, Biochem. Z. 231, 144 



r(1931). 



