Watanabe N, Tsukada N, Smith C R, Phillips M J
Department of Pathology, Hospital for Sick Children, Toronto, Ontario, Canada.
J Cell Biol. 1991 Jun;113(5):1069-80. doi: 10.1083/jcb.113.5.1069.
Modern fluorescence microscopic techniques were used to image the bile canalicular system in the intact rat liver, in vivo. By combining the use of sodium fluorescein secretion into bile, with digitally enhanced fluorescence microscopy and time-lapse video, it was possible to capture and record the canalicular motility events that accompany the secretion of bile in life. Active bile canalicular contractions were found predominantly in zone 1 (periportal) hepatocytes of the liver. The contractile movements were repetitive, forceful, and appeared unidirectional moving bile in a direction towards the portal bile ducts. Contractions were not seen in the network of canaliculi on the surface of the liver. Cytochalasin B administration resulted in reduced canalicular motility, progressive dilation of zone 1 canaliculi, and impairment of bile flow. Canalicular dilations invariably involved the branch points of the canalicular network. The findings add substantively to previous in vitro studies using couplets, and suggest that canalicular contractions contribute physiologically to bile flow in the liver.
现代荧光显微技术被用于对完整大鼠肝脏的胆小管系统进行体内成像。通过将荧光素钠分泌到胆汁中与数字增强荧光显微镜和延时视频相结合，得以捕捉并记录生命过程中伴随胆汁分泌的胆小管运动事件。活跃的胆小管收缩主要见于肝脏的1区（门周）肝细胞。收缩运动是重复性的、有力的，并且似乎是单向的，朝着门静脉胆管方向推动胆汁。在肝脏表面的胆小管网络中未见收缩。给予细胞松弛素B会导致胆小管运动性降低、1区胆小管逐渐扩张以及胆汁流动受损。胆小管扩张总是涉及胆小管网络的分支点。这些发现实质性地补充了之前使用双联体进行的体外研究，并表明胆小管收缩在生理上有助于肝脏中的胆汁流动。
