Fine structure of the common bile duct in adult rats

Abstract

The columnar epithelium of the common bile duct in adult rats contains light and dark cells. Light cells make up 85–90% of the epithelium and show a microvillus luminal border and occasional apical bullous processes. The cytoplasm contains numerous vesicles, small dense granules, and lysosomes. Dark cells are narrower, do not have microvilli, and have an overall electron-dense cytoplasm. Lateral cell interfaces show junctional complexes near the lumen, numerous desmosomes, and complex interdigitations. Intercellular spaces are seen occasionally but are not extensive. Resemblance to the epithelium of the gall bladder in other species is noted.