The Anaerobic Metabolism of Pyruvate in Homogenates of Normal and Neoplastic Rat Tissues

that, under anaerobic conditions, appreciable quantities of pyruvate were metabolized by Flex ner-,Jobling carcinoma homogenates to reduced compounds other than lactic acid. For these stud ies a medium of glycolytic substrates and cofactors was employed in the presence of a “fluorideblock.― This medium permitted the quantitative estima tion of pyruvate metabolism to products other than lactic acid, since little pyruvate was contrib uted to the pyruvate-lactate pool from triose phosphate metabolism through the “fluoride block.― Measurements of these reactions were made by difference from the pyruvate-lactate pool and have been termed “pyruvatedisappearance.― Among the products of “pyruvate disappear ance― found were i,2-propanediol-i-phosphate (PDP)' and an acid-labile phosphate ester postu lated to be acetol phosphate. The present report concerns extension of these studies to homogenates of several normal rat tis sues, investigation of conditions affecting “pyru vate disappearance― in the various tissue homog enates, and development of new methods for the isolation of the reaction products. A preliminary report of this work has appeared (8).