The changes in antioxidans system caused by chlorpyriphos-ethyl in rat brain and protective effect of melatonin and vitamin C + vitamin E

The protective effect of melatonin and the combination of vitamin C and vitamin E on the brain tissue of rats treated with chlorpyriphos-ethyl (CE) was investigated. The experimental groups were as follovvs: Control group (C), CE treated group (CE), vitamin E plus vitamin C treated group (Vit), melatonin treated group (Mel), vitamin E plus vitamin C plus CE treated group (Vit+CE), and melatonin plus CE treated group (Mel+CE). Vitamins and melatonin were administered to appropriate groups six days. CE was applied only fifth and sixth days. İn CE group, comparing with C group, thiobarbituric acid reactive substances was found to increase, vvhereas antioxidant potential was decreased (p<0, W) in brain tissue homogenates. Superoxide dismutase and glutathione peroxidase activities were high in CE group, comparing with C group (p<0,10). These results suggest that CE may cause oxidative stress in rat brain tissues, this oxidative stress may involve in CE toxicity, and melatonin and the combination of vitamin C and vitamin E may decrease these toxic effects caused by CE.