Kinetics of malate dehydrogenase and control of rates of ethanol metabolism in rats.

The theory that the rate of ethanol oxidation is governed by rates of NADH reoxidation is based in part on the observation that the ratio of free cytosolic [NADH]/[NAD+] increases during ethanol metabolism. However, it has recently been suggested that the amount of alcohol dehydrogenase governs rates of ethanol metabolism, which then leaves the change in cytosolic redox state unexplained. In this paper the kinetic parameters for rat liver malate dehydrogenase, determined at 37 degrees C and pH 7.4, are used to provide an explanation for the change in cytosolic redox state that is compatible with rate control by alcohol dehydrogenase.