[Morphometric studies on the growth of bile canaliculi during liver regeneration in rats].

Morphometric analysis of the liver during regeneration after partial hepatectomy showed that the mean area and number of bile canaliculi increased, while the volume density of microvilli related to the lumina of the canaliculi decreased. These changes were observed 12 hours after the operation, which gradually returned to normal on the third day after operation. It indicated that the decrease of volume density of microvilli was the result of enlargement of bile canaliculi, which was different from the decrease of microvilli due to passive widening of the canaliculi such as in cholestasis from loss of microvilli. All these phenomena suggest that enlargement of the area of bile canaliculi during liver regeneration may be due to the increase of membranous protein synthesis. Moreover, the increase of the number of bile canaliculi suggests that the proliferation of hepatocytes is associated with formation of new branches of bile canaliculi.