LIPID-PEROXIDATION AND ANTIOXIDANT SYSTEMS IN RAT-BRAIN - EFFECT OF CHRONIC ALCOHOL-CONSUMPTION

The effect of chronic ethanol exposure, in a liquid diet, on lipid per oxidation and some antioxidant systems of rat brain was investigated. Chronic ethanol administration induced a greater susceptibility to iro n/ascorbate-induced lipid peroxidation, estimated as thiobarbituric re active substances (TEARS) production, in the microsomal fraction, but a lower lipid peroxidation in the total homogenate. Glutathione (GSH) levels as well as GSH peroxidase and GSH reductase were unaffected, wh ile the activity of Cu-Zn superoxide dismutase was decreased and that of catalase increased. Lipid peroxidation experiments performed in the presence of some hydroxyl radical scavengers suggested that a greater OH. generation may be responsible of the greater TEARS production in the microsomal fraction of ethanol treated rats; differently, in total homogenate of control and ethanol rats a relationship was found betwe en the redox stale of iron and TEARS production, suggesting that the l ower lipid peroxidation in treated rats may depend on a different modu lation of the iron redox state.