322 ASCORBIC ACID 



distribution of calcium between the cells and extracellular fluids of the 

 skeletal muscles and liver in dogs and concluded that, imless some of the 

 calcium is within the cells, a part of it must be in an un-ionized combination 

 with some extracellular substance other than the protein of the extracellular 

 fluid. They did not suggest, however, the possibility of a linkage of a portion 

 of the calcium with a constituent of an intercellular cement substance to 

 form a difficultly soluble compound. In tests with radioactive ascorbic acid, 

 Burns et al. recently reported'^ finding a higher specific radioactivity in the 

 teeth than in organs such as the adrenals. Their results suggest fixation 

 and concentration of the radioactive material in the teeth, but it seems 

 doubtful that all the material could be ascorbic acid as such, however. 

 The finding in the teeth of radioactive carbon originating from ascorbic 

 acid suggests a relation between the metabolism of calcium and ascorbic 

 acid. It seems possible that ascorbic acid may be transported as calcium 

 ascorbate to calcification areas where it is, at least in part, metabolized to 

 carbon dioxide and deposited as carbonate. 



(2) Phosphorus. Newcomb-''^ suggested that the ascorbic acid-oxidase 

 system in plant tissues may serve to generate energy-rich phosphate by the 

 oxidation of phosphoascorbate, a substance which has not been identified 

 as a constituent of either plant or animal tissues. In scorbutic animals 

 changes in phosphorus metabolism may be entirely secondary to the changes 

 in calcium. Some workers have found that disturbances in phosphorus 

 metabolism in scurvy are of a relatively low order^^" whereas others have 

 reported a fall in blood phosphate in scurvy. ^^^"^^^ Ascorbic acid appears to 

 play a part in the formation or stabilization of alkaline phosphatase, an 

 enzyme, the level of which is reduced markedly in severe scurvy.^*' -^^• 

 314-319 Bourne^'^ suggested that "one of the functions of vitamin C is to 

 allow the production of a phosphatase-impregnated bone matrix upon which 

 bone salt is immediately deposited." 



Horvath and Tebbe^-° found only minor variations in the concentration 

 of the various phosphorus compounds in the gastrocnemius muscle of scor- 

 butic guinea pigs during the first 16 days on the deficient diet. With the 

 onset of deficiency symptoms following this period, the levels decreased 



^"- H. von Euler and K. Myrback, Hoppe-Seyler's Z. phijsiol. Chem. 148, 180 (1925). 



312 H. Leone, Riv. din. pedia. 32, 1185 (1934). 



313 R. Matricardi, Riv. din. pediat. 36, 351 (1938). 



31^ H. Schwachman and B. S. Gould, J. Nutrition 23, 271 (1942). 



315 B. S. Gould and H. Schwachman, Am. J. Physiol. 135, 485 (1942). 



31" G. H. Bourne, J. Physiol. (London) 102, 319 (1943). 



31' W. O. Russell, E. T. Rouse, and J. A. Read, Arch. Pathol. 38, 40 (1944). 



318 H. R. Perkins and S. S. Zilva, Biochem. J. 47, 306 (1950). 



SIS' H. Bunting and F. R. White, Arch. Pathol. 49, 590 (1950). 



320 S. M. Horvath and D. Tebbe, /. Biol. Chem. 165, 657 (1946). 



