Effect of ethanol treatment on indices of cumulative oxidative stress.

The effect of ethanol exposure upon several parameters relating to oxidative stress has been examined in brain and liver. A single administration of either acetaldehyde or ethanol was able to enhance rates of generation of reactive oxygen species in liver but this effect was not apparent in the cerebral cortex. Glutamine synthetase is especially sensitive to inactivation by free radicals and evidence for cumulative oxidative damage to this enzyme was found in liver and to a lesser extent in cerebral cortex. This enzyme was depressed in liver after both a single injection of acetaldehyde or ethanol, or after more extended dosing. The liver was also more susceptible than cerebral cortex, to pro-oxidant effects as judged by depression of glutathione after acute dosing with either solvent. Enzyme inhibition representing temporally summated oxidative events may be a more sensitive procedure than direct measurement of rates of formation of active oxygen species and may find especially utility in the detection of prolonged low level pro-oxidant activity.