Dynamics of serum and tissue alkaline phosphatase activity after hepatectomy in normal and cirrhotic rat liver

Abstract

To investigate the pathogenesis of bile stasis after partial hepatectomy in the cirrhotic liver, the activity of alkaline phosphatase in serum and liver tissue, as well as morphologic changes in the bile canaliculi, were compared between cirrhotic and normal rats. In the normal rats, and cirrhotic rats produced by intraperitoneal thioacetamide injection, blood and liver specimens were obtained before and 2, 7, and 14 days after 70% partial hepatectomy. Serum and liver tissue alkaline phosphatase (ALPase) activity, liver weight, and electron histochemical changes in the bile canaliculi and microvilli were assessed. The normal rats showed rapid regeneration and marked elevation in the serum hepatic and tissue ALPase with a peak on day 2. This was associated with the maximal bile canalicular dilation and increased pericanalicular lipid vesicles, but without the microvilli destruction. These changes were normalized by 14 days after hepatectomy. In contrast, in the cirrhotic rats, regeneration and elevation in the serum and tissue ALPase were delayed, and higher total bile acidemia persisted. The bile canaliculi with ectasia before hepatectomy underwent no further dilation, and was associated with marked destruction of the microvilli and weakened ALPase in the bile canalicular membrane. The pericanalicular lipid vesicles was sparse. Persistent cholestasis in the remnant cirrhotic liver after hepatectomy is closely linked to the morphologic derangement and ALPase activity in the intra- and peri-bile canalicular area, and serum ALPase is useful as an index monitoring bile secretory capacity of the remnant liver.