Rate-limiting steps in ethanol metabolism and approaches to changing these rates biochemically.

Ethanol is oxidized to acetate primarily by a system involving liver alcohol and aldehyde dehydrogenases coupled with reoxidation of NADH by the mitochondria. All of these steps are at least partially rate-limiting in ethanol metabolism, with alcohol dehydrogenase and oxidative phosphorylation probably slower than the others. More research is required to assess the quantitative roles of various steps. Many agents are ineffective in changing the rate of metabolism of ethanol, but fructose and dinitrophenol may increase the rate by up to 1.5-fold in vivo. The failure of single agents to increase the rate substantially may indicate that when one step is accelerated, another step becomes rate-limited. Therefore, combinations of agents that affect several steps simultaneously may be required for acceleration. Effective experimental methods for inhibiting alcohol dehydrogenase in vivo are available.