Fig. 1
From: The usefulness of lactate dehydrogenase measurements in current oncological practice
Scheme showing the LDH reaction. LDH catalyzes the reversible conversion of pyruvate to lactate with NADH as a cofactor during glycolysis. The LD5 isoform preferentially catalyzes the reduction of pyruvate into lactate and thus prevents entry of pyruvate to the tricarboxylic acid (TCA) cycle. The NADH oxidation allows the regeneration of NAD+ molecules, which are needed for the continuous generation of ATP to maintain glycolysis. By contrast, the LD1 is predisposed to convert lactate into pyruvate with the concomitant generation of NADH