Hypothesis: energy wastage in alcoholism and drug abuse: possible role of hepatic microsomal enzymes.

Hepatic microsomal drug oxidation appears to be an energy-wasteful process because it has no known link with energy-conserving mechanisms such as the synthesis of ATP, and in addition it requires the uncoupled oxidation of NADPH. It is postulated that this can appreciably alter the energy balance of the whole body under certain conditions. Such an imbalance would be favored by the repeated intake of drugs that induce hepatic microsomal enzymes and by the provision of ethanol as a major source of calories. The hypothesis is consistent with the changes in body weight in humans and animals after chronic ethanol intake. It is supported by observations of an increased oxygen consumption in rats given ethanol or barbiturates in doses that induce hepatic microsomal enzymes.