Hepatic catalase and superoxide dismutases after acute ethanol administration in rats

The administration of an acute ethanol load (2.3 g/kg, IP) to rats is followed by a decrease of the hepatic activity of cytosolic catalase, a decrease which precedes a reduction in the cytosolic Cu, Zn-superoxide dismutase (SOD) activity. Desferrioxamine, an iron chelator and scavenger of superoxide radicals, administered prior to ethanol, prevents the changes in the cytosolic catalase activity, changes which are unaffected by the administration of allopurinol, an inhibitor of xanthine oxidase. These data favour the hypothesis that acute ethanol results in an overproduction of oxygen free radicals which affects primarily the cytosolic catalase activity and increases hereby susceptibility of Cu, Zn-SOD to these radicals. They suggest also that xanthine oxidase does not play a major role in oxygen radical production in the liver cytosol during acute alcohol intoxication.