ABSTRACT
Diazinon [DZN] is an organophosphate pesticide that widely used for agricultural pest control all over the world. DZN affects target organs including reproductive system by inhibiting the activity of acetylcholinesterase and inducing oxidative stress. Vitamin E [alpha-tocopherol] is a strong antioxidant which inhibits free radicals, and probably can reduce lipid perxidation effectively in biological systems. The present study, aimed to evaluate the effects of DZN on malondialdehyde [MDA] and glutathione [GSH] levels in testis of rats and protective effect of vitamin E. In this experimental study, thirty adult male Wistar rats [200-250 gr] were divided into 5 groups [n= 6]: control group [did not receive any material], sham group [received only pure olive oil], experimental group 1 [DZN, 60 mg/kg], experimental group 2 [Vit E, 200 mg/kg] and experimental group 3 [DZN+Vit E, with the same dose]. All groups were sacrificed after 6 weeks and right testis was used to measure the MDA and GSH levels. The amount of MDA was determined by the thiobarbituric acid assay and 5, 5-Dithio-bis [2nitrobenzoic acid] DTNB-recycling protocol was used for GSH assay. The results showed that DZN increased MDA level [p<0.001] and reduced GSH level [p<0.001]. Administration of DZN plus vitamin E decreased the MDA level [p<0.001] and increased GSH level [p=0.001]. DZN induced lipid peroxidation in the testis of rats. Vitamin E by its antioxidant activity was able to improve the toxic effect of DZN