Histological and histochemical alterations in the liver induced by lead chronic toxicity.

Adult males of the Wistar albino rats (Rattus norvegicus) were exposed to lead acetate trihydrate in drinking water (0.0%, 0.25%, 0.5%, 1% and 2% for 1-12 months) to investigate histological and histochemical alterations induced by lead intoxication in the liver. Chronic exposure to subtoxic concentrations of lead produced changes in the hepatocytes, portal triads and the sinusoids. The alterations in the hepatocytes were mainly anisokaryosis, nuclear vesiculation, binucleation, cytoplasmic inclusions, cytoplasmic swelling, hydropic degeneration, necrosis and reduction in glycogen content. In addition, portal triads mild chronic inflammation, Kupffer cells hyperplasia and occasional fatty change were seen together with hemosiderosis. No portal fibrosis or cirrhosis was detected due to chronic subtoxic doses of lead exposure in the liver of any member of the dose groups over the entire period of the study. Chronic lead exposure also increased the activities of alkaline phosphatase and α-glycerophosphate-dehydrogenase which might be an adaptation to the metabolic, structural and functional changes in the organelles of hepatic cells due to lead intoxication. The findings revealed that chronic exposure to lead produced significant histological and histochemical changes in the liver of the Wistar albino rats.