Evidence for Fluid-Phase Pinocytosis of Extrahepatic Bile Duct Cells Isolated from Normal Rats in Culture

Cell Structure and Function

Michio Mori¹  Gen Yamada¹  Norimasa Sawada¹ 

[1] Departments of Pathology, Sapporo Medical College

关键词: cysteine;    granulocyte-colony stimulating factor;    site-directed mutagenesis;    thermostability;   

DOI  :  10.1247/csf.17.67

学科分类：分子生物学，细胞生物学和基因

来源: Japan Society for Cell Biology

【 摘 要 】

References(19)Cited-By(4)In order to elucidate the physiological function of extrahepatic bile duct cells, we isolated epithelial cells from the rat extrahepatic bile duct by digesting resected segments of the extrahepatic bile duct with 0.15% trypsin in ice-cold Ca2+-free Hanks' balanced salt solution supplemented with 0.25 mM EDTA overnight. As a result, the epithelial cells were collected as aggregates and attached to culture dishes coated with type I collagen. Approximately 95% of the cells cultured for 24 hrs were found to be positive for γ-glutamyl transpeptidase and cytokeratin-19, but negative for vimentin. These characteristics were identical to the features of rat extrahepatic biliary epithelial cells in situ. Ultrastructurally, the cells were long and columnar in configuration on the 2nd day in culture, and possessed numerous microvilli at the apical surface and well-developed junctional complexesat the lateral surface. These findings also indicate that the cells maintain an epithelial nature and are morphologically polarized. When the cells were exposed to a low dose of horseradish peroxidase (HRP) on the 2nd day in culture, which was followed by fixation and treatment with 3-3' -diaminobenzidine, HRP was found preferentially in the cytoplasmic vesicles near the apical surface. HRP was then observed in the intercellular spaces; however, the electron-dense tracer, ruthenium red, did not permeate into the intercellular spaces, and HRP was found in neither cytoplasms nor intercellular spaces when the cells were incubated in HRP-containing medium at 4°C for 30 min. These results suggest that the extrahepatic bile duct epithelial cells are involved in the reabsorption of bile constituents.

【 授权许可】

Unknown