THE EFFECTS OF GENTAMICIN AND VITAMIN-E ON ENZYMATIC ANTIOXIDANT DEFENSE IN GUINEA-PIG LUNG

Objective: To study the possible effects of gentamicin on the enzymic free-radical defence system in the lung. Method: Activities of cytopla smic superoxide dismutase (CuZn-SOD), mitochondrial superoxide dismuta se (Mn-SOD), glutathione peroxidase (GSH-rx) and catalase (CAT) enzyme s were studied in lung tissues from gentamicin-treated guinea-pigs com pared to controls. Results: Levels of those enzymes were higher in the gentamicin group except for xanthine oxidase (XO) activity. Vitamin E given concomitantly with gentamicin caused significant decreases in C uZn-SOD, Mn-SOD and GSH-Px activities but an increase in CAT activity in the lung tissue. Only vitamin treatment caused significant decrease s in the activities of CuZn-SOD, Mn-SOD and GSH-Px enzymes and an incr ease in CAT activity. Conclusion: The results suggest that lung tissue is able to respond quickly and effectively against the adverse effect s of some oxidant substances by inducing and/or activating the enzymat ic free-radical defence system.