GALLSTONE FORMATION

Abstract

Cholesterol, the major component of Summary gallstones, is held in solution in the bile by formation of micelles in which phospholipids and bile-salts are involved. The ratio of cholesterol to bile-salts plus phospholipids determines cholesterol solubility. Although the bile produced by the liver in patients with gallstones is abnormal, some features of gallbladder function might favour stone formation. Of the hepatic factors contributing to gallstone formation a high cholesterol content of bile, a low bile-salt pool, and interruption of the enterohepatic circulation seem to be important. One hypothesis for gallstone formation relates to events at the plasma membrane of the bile canaliculus, but whether the critical factor here is an increase in the amount of cholesterol passing through the membrane or an abnormal cholesterol to phospholipid ratio remains controversial. It seems likely that an understanding of the mechanism for gallstone formation will come from an investigation of the problem at the cellular, subcellular, or molecular level. This review ends with a note on the prospects for treatment, which should be directed at affecting the cholesterol to phospholipid plus bile-salt ratio or at the cholesterol precipitate directly by using detergent agents.