Lactic and Pyruvic Acid Relations in Contracting Mammalian Muscle

¹ From the Department of Chemistry, University of Arkansas, Fayetteville, Arkansas

Tetanic contraction of mammalian muscle under essentially anaerobic conditions was found to result in marked increase in the pyruvic acid content as well as in the lactic acid content. The increase in lactic acid content was proportionately greater than in the pyruvic acid content. Repeated single twitches at a rate of 1/sec., continued long enough to produce a steady state, resulted in only a slight increase in pyruvic acid content, with a marked decrease in the ratio of pyruvic to lactic acid. The pyruvic acid formed during the steady state of activity appears not to pass into the blood stream.