STRESS PROTEINS AND SH-GROUPS IN OXIDANT-INDUCED CELL-DAMAGE AFTER ACUTE ETHANOL ADMINISTRATION IN RAT

It is generally accepted that lipid peroxides play an important role i n the pathogenesis of ethanol-induced cellular injury and that free su lfhydryl groups are vital in cellular defense against endogenous or ex ogenous oxidants. It has been observed that oxidative stress induces t he synthesis of the 70-kDa family of heat-shock proteins (HSPs). Furth ermore, induction of HSPs represents an essential and highly conserved cellular response to a variety of stressful stimuli. In the present s tudy, we measured the intracellular levels of HSP 70 proteins after ad ministration of mild intoxicating and grossly intoxicating doses of et hanol to rats. Our results demonstrate that elevated doses of ethanol induce HSP in various brain areas, namely, cerebellum, hippocampus, an d to a lesser extent, striatum or liver. Induction of HSP 70 protein w as correlated with a marked depletion of intracellular bound thiols an d a decrease in lipid peroxidation measured as MDA formation. These st udies support the hypothesis that a redox mechanism may be involved in the heat-shock signal pathway.