Sustained spatial disturbance of bile canalicular networks during regeneration of the steatotic rat liver.

Abstract

Although it is generally considered that livers with moderate steatosis can be safely used in the setting of living-donor liver transplantation, the effect of the regenerative process of such a graft on postoperative liver function is incompletely understood. We assessed the morphologic and functional alterations during the regeneration of fatty liver, with special reference to the biliary system. Wistar rats with normal or fatty livers induced by a choline-deficient diet were subjected to 70% partial hepatectomy (PH). The regenerated liver weight and serum parameters were compared. Furthermore, to assess the spatial alterations of bile canalicular networks, the distribution of AGp110, a fibronectin receptor that localizes on the apical (bile canalicular) membrane of the hepatocytes, was analyzed immunohistochemically. The serum albumin levels of the fatty-liver rats decreased significantly after 24 hours, and this continued until day 7. The increase in the total bile acid levels of the fatty-liver group was higher and more prolonged compared with that of the normal-liver group. At 24 hours after PH, discontinuity of the AGp110-positive canalicular network was evident in both groups. At 7 days after PH, the typical AGp110-positive canalicular network was almost restored in the normal-liver group. In contrast, the fatty-liver group showed sustained discontinuity of canalicular networks at the same time point. The livers with moderate steatosis are associated with prolonged cholestasis after 70% PH, and this was caused, in part, by sustained spatial disturbance of bile canalicular networks during the regenerative process.