Bile canaliculi morphology after bile duct ligation in the rat with portacaval shunt: a time course study.

Besides the spontaneous occurrence of portacaval shunts in chronic liver diseases and the performance of shunt to cure portal hypertension, shunts are now proposed for the treatment of some metabolic diseases, especially in children. The portacaval shunt model in the rat, known to induce liver atrophy related to hepatocyte loss and atrophy, was used to investigate morphological liver changes occurring in cholestasis. Two weeks after portacaval or sham portacaval shunt, the bile duct was ligated and livers were examined by light and electron microscopy at 5 h, 20 h, 4 days and 8 days. Portal inflammatory reaction and proliferation of bile ducts were identical but areas of patchy hepatic necrosis were more numerous in shunted rats. Hepatocyte size decreased in the sham group but increased in the other group. Hepatocyte ultrastructural changes were similar in the two groups. At 5 h, the number of bile canaliculi sections increased (X2) and 95% of them were normal. As time elapsed, the ratio of dilated bile canaliculi without microvilli and of bile canaliculi filled with cytoplasmic blebs increased but in no case reached 50% of the total. These results show that in the rat, cholestasis induced by bile duct ligation has approximately the same characteristics in control or shunted animals.