RADIOACTIVE PHOSPHORUS AS A TRACER IN ANAEROBIC MUSCULAR CONTRACTION

Abstract

Radioactive P, in the form of disodium phosphate, was injected subcut. into amytalized cats. After 2 hours, one gastrocnemius was tetanized for 15 sees., and the distr. of the radiophosphorus among the various P compounds of the resting and stimulated muscles compared. The highest cone, was found in inorg. P of the resting muscle. The changes produced on stimulation were those corresponding to observed changes in P distr., i.e., hydrolysis of some phosphoereatine, and conversion of some phosphocreatine-P to hexosemonophosphate. No evidence was found that the formation of lactic acid in contraction involves the phosphate transfers postulated by the Embden-Meyerhof schema of glycolysis.