Lipid Peroxidation and Antioxidant Enzymes in Rat Tissues in Pyrethroid Toxicity: Possible Involvement of Reactive Oxygen Species

Abstract

Pyrethroids (cypermethrin and fenvalerate) have high pesticidal activity and low toxicity to non-target organisms. Organochlorines and, recently, organophosphates have been shown to produce oxidative stress through the generation of free oxygen radicals. However, there are no reports which show involvement of reactive oxygen species (ROS) in pyrethroid toxicity. The present study was undertaken to determine pyrethroid-induced lipid peroxidation (LPO) and to show whether pyrethroid intoxication alters the antioxidant system. Male Wistar rats weighing 150-180 g were administered a single dose of 0.001% LD50 cypermethrin and/or fenvalerate orally and the rats were sacrificed at 0, 1, 3, 7 and 14 days of treatment. Liver, kidney and heart tissues were removed and washed in phosphate buffered saline pH 7.4. The tissues were homogenized and samples were centrifuged to obtain cytosolic fraction. LPO, antioxidant enzymes such as superoxide dismutase (SOD), catalase (CAT), glutathione-S-transferase (GST) and gluta...