Ameliorative Effect of Zinc on Chlorpyrifos-Induced Erythrocyte Fragility in Wistar Rats

Abstract

Oxidative stress has been implicated in the molecular mechanism of chlorpyrifos (CPF) poisoning. The present study was aimed at evaluating the ameliorative effect of zinc, an antioxidant trace element, on lipoperoxidative changes and erythrocyte fragility induced by subchronic CPF exposure in Wistar rats. Twenty adult Wistar rats divided into 4 groups of 5 animals each were used as experimental subjects. Rats in groups I (S/oil group) and II (CPF group) were exposed to soya oil only (2 ml/kg) and CPF only (10.6 mg/kg~ 1/8 th LD 50 ), respectively. Group III (Zn group) were dosed with zinc only (50 mg/kg) while in group IV (Zn+CPF), Zn (50 mg/kg) were co-administered with CPF (10.6 mg/kg). These regimens were administered orally once daily for a period of 8 weeks. At the end of the study, the rats were sacrificed and erythrocytes analysed for erythrocyte osmotic fragility and malonaldehyde (MDA) concentration as an index of lipoperoxidative changes. Erythrocyte fragility was significantly increased ( P < 0.01) in CPF group compared to S/oil, Zn and Zn+CPF groups, respectively. Similarly, the CPF group showed a significant increase (P < 0.01) in MDA concentration compared to S/oil, Zn and Zn+CPF groups, respectively.The present study has shown that repeated exposure of rats to CPF increased erythrocyte fragility partly due to oxidative hemolysis resulting from increased lipoperoxidative changes. (New York Science Journal 2010;3(5):117-122). (ISSN 1554 - 0200).