The effects of gentamicin and vitamin E on enzymatic antioxidant defence 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 cytoplasmic superoxide dismutase (CuZn-SOD), mitochondrial superoxide dismutase (Mn-SOD), glutathione peroxidase (GSH-Px) and catalase (CAT) enzymes were studied in lung tissues from gentamicin-treated guinea-pigs compared 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 CuZn-SOD, Mn-SOD and GSH-Px activities but an increase in CAT activity in the lung tissue. Only vitamin treatment caused significant decreases in the activities of CuZn-SOD, Mn-SOD and GSH-Px enzymes and an increase in CAT activity.

Conclusion: The results suggest that lung tissue is able to respond quickly and effectively against the adverse effects of some oxidant substances by inducing and/or activating the enzymatic free-radical defence system.