Cholangiocyte

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Cholangiocyte
Details
Identifiers
Latin cholangiocytus
Code TH H3.04.05.0.00011
Anatomical terminology

Cholangiocytes are the epithelial cells of the bile duct.[1] They are cuboidal epithelium in the small interlobular bile ducts, but become columnar and mucus secreting in larger bile ducts approaching the porta hepatis and the extrahepatic ducts.

Function[edit]

In the healthy liver, cholangiocytes contribute to bile secretion via net release of bicarbonate and water. Several hormones and locally acting mediators are known to contribute to cholangiocyte fluid/electrolyte secretion. These include secretin, acetylcholine, ATP, and bombesin.

Cholangiocytes act through bile-acid independent bile flow, which is driven by the active transport of electrolytes. In contrast, hepatocytes secrete bile through bile-acid dependent bile flow, which is coupled to canalicular secretion of bile acids via ATP-driven transporters. This results in passive transcellular and paracellular secretion of fluid and electrolytes through an osmotic effect.

Diseases[edit]

Importantly, cholangiocytes are the target of disease in a variety of conditions often known as "cholangiopathies". These diseases include primary biliary cirrhosis, primary sclerosing cholangitis, AIDS cholangiopathy, disappearing bile duct syndromes, Alagille's syndrome, cystic fibrosis, and biliary atresia. As a group, cholangiopathies account for approximately 18% of adult liver transplantations and the majority of pediatric liver transplantations.

Active scientific investigation of cholangiocytes focuses on such diverse processes as mechanisms of fluid/electrolyte secretion, regulation of cholangiocyte proliferation, roles of cholangiocytes in the pathogenesis of liver fibrosis and cirrhosis, and cholangiocyte apoptosis. Specific investigation of individual cholangiopathies is also pursued actively.[1]

References[edit]

  1. ^ a b Tietz PS, Larusso NF (May 2006). "Cholangiocyte biology". Current Opinion in Gastroenterology. 22 (3): 279–87. PMID 16550043. doi:10.1097/01.mog.0000218965.78558.bc.