The metabolism of lactic and pyruvic acids in normal and tumour tissues

Abstract

IN the first paper of this series [Elliott and Schroeder, 1934] a study was made by manometric and analytical methods of the oxidative breakdown of lactic and pyruvic acids in rabbit kidney cortex. It appeared that lactate is first oxidised to pyruvate and that the main course of the removal of pyruvate follows a cycle of reactions similar to that put forward by Toenniessen and Brinkman [1930] for muscle tissue. This cycle involves the oxidation of 2 mols. of pyruvic acid, probably by way of an unknown intermediary, to 1 mol. of succinic acid; succinate is then oxidised to fumarate, which, after conversion into malate, is oxidised to oxaloacetate, and oxaloacetate is decarboxylated yielding 1 mol. of pyruvate. The series of reactions is illustrated by the following scheme: 2CH3.0CHOH.COO -4H (-2H +20 \ 2CH3. 0 .COOH +H2.CO.COOH CH2.COOH V H2.CO.COOH H2. COOH -C2 (hypothetical) -211 CO.COOH -2H CH(OH).COOH +1H20 CH0.C000H &H2.COOH cH2.O00H JR.COOH