[Status of the antioxidant protective system of rat liver exposed to carbon tetrachloride]

The dynamics of enzyme activity of antioxidative protective system of the liver and the content of restored glutathione have been studied in rats poisoned by CCl4 injection. During the first hours followed the injection against the background of maximum accumulation of dienic conjugates and decrease of the restored glutathione level no significant changes in the enzyme activity of the antioxidative protective liver system were observed. At the same time 48 hours later the superoxide dismutase and catalase activity decreased by 38% and 36%, respectively, with relative stability of glutathione-dependent enzymes and a two-fold increase of the restored glutathione level. It is shown that a fall of activity of the cytoplasmic antioxidative liver enzymes is not a result of the immediate inactivating effect of free-radical reactions initiated by CCl4, but is, evidently, caused by the covalent binding of its radical metabolites with corresponding macromolecules.