Liver profile of rats after long-term ingestion of different doses of chlorpyrifos

Male Wistar rats were separated into three groups of 25 each. Animals in group A (GA) served as control, group B (GB) were daily administered orally chlorpyrifos at a dose of 5 mg/kg b wt and animals in group C (GC) received daily an oral administration of chlorpyrifos (Anu Products Ltd., India) at a dose of 10 mg/kg b wt. Rats were sacrificed 24 h after last dose on 1st, 2nd, 4th, 6th, and 8th week after initiation of the experiment. Small pieces of liver were extirpated and fixed in aqueous Bouin's solution. The tissues thus fixed were routinely processed for histological studies. The present study showed that the histopathological changes were caused in liver of rats by chlorpyrifos administration. The changes noticed were mainly hepatocytic vacuolation, degeneration of hepatocytes and their nuclei, hyperchromatic and hypertrophied nuclei at earlier stage of treatment, sinusoidal dilation and focal necrosis. However, variable intensities of these changes were noticed depending upon the doses and duration of the treatment.