Impaired gallbladder motility is an established factor stone disease may initially represent a metabolic liver in cholesterol gallstone formation. We assessed whether disorder but can be modulated by the enterohepatic altered small intestinal smooth muscle contractility with circulation of bile salts.2,9-14 The gallbladder (by filling slow transit might potentiate gallstone formation by fur-and emptying) and the small intestine (by governing ther impeding enterohepatic cycling of bile acids. transit time) are the rate-limiting steps that control Ground squirrels were fed a 1% or a trace (controls) cho-the enterohepatic cycling frequency of bile salts and lesterol diet. Small intestinal transit was evaluated from their flux through the liver. [9][10]14,15 Enterohepatic cy- size calculated by isotope dilution. Gas-liquid chromaProlonged small intestinal transit, like impaired tography (GLC) assessed bile salt profile. In animals on gallbladder emptying, should hinder enterohepatic cythe 1% cholesterol diet, aboral transit was significantly cling and lower the bile salt secretion rate, thus predisdelayed, the maximal contractile response to betha-posing to the formation of gallbladder bile saturated nechol was markedly increased (P õ .05) with no change with cholesterol.9,10,14 Recent studies of cholesterol gallin median effective concentration in either circular or stone pathogenesis in nonobese subjects and in acromelongitudinal muscle strips from both the jejunum and galic patients treated with the long-acting somatoileum, and the gallbladder contractile responses to bethanechol and cholecystokinin (CCK) were decreased. statin analog, octreotide, support and advance this Cholesterol saturation index and the fraction of deoxy-hypothesis. In each condition, either prolonged wholecholic acid in the pool doubled, whereas the total bile gut transit or lengthened small intestinal transit has salt pool size remained unchanged in cholesterol-fed an-been linked to an increased production of deoxycholate, imals. In this model, a high-cholesterol diet is associated saturated gallbladder bile, and the subsequent formawith altered small intestinal smooth muscle contractility tion of cholesterol gallstones. [16][17][18] The importance of the
