Biochemical and behavioral deficits in adult rat following chronic dichlorvos exposure.

The present study was carried out to assess the biochemical and behavioral sequelae of chronic dichlorvos (6 mg/kg b.wt/day for 8 weeks) exposure in rats. Dichlorvos administration significantly decreased the activities of neuropathy target esterase and other carboxylesterase viz., paraoxon resistant and mipafox and paraoxon resistant esterases. The acetylcholinesterase activity was also appreciably decreased following dichlorvos exposure. The alterations in biochemical parameters were also reflected in the behavioral patterns of dichlorvos-treated animals. Dichlorvos administration caused a marked decrease in both the ambulatory and stereotypic components of spontaneous locomotor activity of rats. The muscle strength and coordination of the dichlorvos-treated animals was also significantly impaired. Besides, a marked deterioration in the memory function assessed in terms of the conditioned avoidance response was discernible at the end of the treatment schedule in the experimental animals.