title: Increased microfilaments in hepatocytes and biliary ductular cells in cholestatic liver diseases.
abstract: To assess the extent of microfilaments in cholestatic liver diseases we examined the cytoplasmic microfilaments in intrahepatic and extrahepatic cholestasis in man by electron microscopy. Study subjects were two patients with drug-induced intrahepatic cholestasis, three patients with intrahepatic cholestasis due to viral hepatitis, four patients with extrahepatic cholestasis due to stones of the common bile duct and two patients with primary biliary cirrhosis. Two biopsied specimens from patients without clinical or histological evidence of liver disease served as noncholestatic controls. The microfilaments in hepatocytes and biliary ductular cells were significantly increased in cholestasis compared with those in non-cholestatic controls. Well developed bundles of microfilaments were noted around the pericanalicular ectoplasm and seemed to be parallel to plasma membrane of the hepatocytes in cholestasis. In cholestasis, there were increased bundles of microfilaments around the periluminal region, lateral cell wall, and nucleus of biliary ductular cells. Two patterns of microfilaments bundles (fine microfilamentous network and spindle-shaped dense or clusters of microfilaments) were associated with cholestasis. The clustered form of microfilaments also seemed to be clearly associated with intracytoplasmic vacuoles containing bile salts. In conclusion, the increase of microfilaments in hepatocytes and biliary ductular cells may be the consequence of various forms of cholestasis. Further studies are needed to clarify the functional significance of increased microfilaments in cholestasis.
authors.affiliation: Department of Internal Medicine, Medical College, Catholic University of Korea, Seoul, Korea. kwchung@cmc.cuk.ac.kr
authors.forename: Kyu-Won
authors.initials: KW
authors.lastname: Chung
authors.forename: Nam-Ik
authors.initials: NI
authors.lastname: Han
authors.forename: Sang-Wook
authors.initials: SW
authors.lastname: Choi
authors.forename: Byung-Min
authors.initials: BM
authors.lastname: Ahn
authors.forename: Seung-Kyu
authors.initials: SK
authors.lastname: Yoon
authors.forename: Soon-Woo
authors.initials: SW
authors.lastname: Nam
authors.forename: Young-Sok
authors.initials: YS
authors.lastname: Lee
authors.forename: Jun-Yeol
authors.initials: JY
authors.lastname: Han
authors.forename: Hee-Sik
authors.initials: HS
authors.lastname: Sun
mesh_terms: D008841:Actin Cytoskeleton / Q000473:pathology* / Q000648:ultrastructure; D001648:Bile Canaliculi / Q000473:pathology* / Q000648:ultrastructure; D001706:Biopsy; D002780:Cholestasis, Intrahepatic / Q000473:pathology*; D022781:Hepatocytes / Q000473:pathology* / Q000648:ultrastructure; D006801:Humans; D008854:Microscopy, Electron