Biochemical and haematological changes in peripheral blood of rats exposed to chlorpyrifos: protective effect of vitamins A and E combination

Chlorpyrifos is a highly toxic organophosphate compound. It is still among the most widely used insecticide, and the main mechanism of its toxicity is associated with inhibition of cholinesterases. Aong with the anticholinesterase action, CPF may affect other biochemical mechanisms, particularly through disrupting pro- and antioxidant balance and inducing free-radical oxidative stress. We studied the action of A and E vitamins on the basic haematological and biochemical parameters of rat peripheral blood after 12 hours of a single chlorpyrifos intoxication. Exposure to 70 mg/kg chlorpyrifos caused a decrease in the total number of red blood cells (RBCs), platelets, and total haemoglobin content. We also observed a decrease in the acid haemolysis resistance of RBCs in peripheral blood of CPF-poisoned rats. Combined exposure to chlorpyrifos and vitamins A and E caused changes in haemolysis resistance of RBCs, approaching the control values. In addition, it was found that chlorpyrifos intoxication disrupts prooxidant-antioxidant balance as evidenced by the increase of lipid peroxidation products: lipid hydroperoxides and thiobarbituric acid reactive substances. However, administration of vitamins A and E during intoxication provided a levelling effect on the formation of lipid peroxidation products. CPF intoxication caused an increase of the catalase activity while superoxide dismutase, glutathione peroxidase and glutathione reductase activities and the content of reduced glutathione decreased. It was revealed that combination of vitamins A and E cause corrective effect at the platelets quantity, and lipid hydroperoxides thiobarbituric acid reactive substances amount of rat peripheral blood.