[Bile formation and cholestasis].

[benign recurrent intrahepatic cholestasis]

Transport proteins in hepatocytes and bile duct epithelium mediate uptake and secretion of cholephilic compounds in the liver and are involved in bile formation . Many of these proteins have recently been cloned and characterized and appear to belong to large gene families . Apart from the liver these proteins are expressed in the blood -brain barrier , placenta , kidneys , lungs , intestine and seminiferous tubules . Prokaryotes and yeasts contain similar proteins . In cancer cells they are involved in multidrug resistance . Some genetic cholestatic liver diseases , including progressive familial intrahepatic cholestasis , Dubin-Johnson syndrome , benign recurrent intrahepatic cholestasis and intrahepatic cholestasis of pregnancy result from mutations in transport protein genes . These proteins also play a role in drug-induced liver disease and in primary biliary cirrhosis . Cyclosporine and oestradiol (glucuronide ) for instance inhibit bile salt export protein (BSEP ).