Relationship between gallbladder contraction and progesterone receptors in patients with gallstones

Stasis of bile within the gallbladder has long been suspected of having an important role in the pathogenesis of gallstone disease. We postulated that the female preponderance of gallstone disease might partly be related to the effects of progesterone, a known smooth muscle relaxant, on specific receptors in the gallbladder wall, leading to stasis of bile. A total of 42 patients with gallstone disease and 28 control subjects underwent radionuclide scan imaging and their gallbladder ejection fractions were calculated in response to intravenous infusion of cholecystokinin octapeptide. Patients then underwent cholecystectomy and a piece of gallbladder fundus was assayed for the presence of progesterone receptors. Receptors were present in 60 percent of patients. As a group, gallstone patients had a decreased ejection fraction compared with control subjects. The presence of progesterone receptors in the gallbladder wall was associated with a decreased percentage of ejection compared with both healthy control subjects and patients whose gallbladders were receptor-negative. We conclude that progesterone receptors are present in the gallbladder wall of gallstone patients and that their presence correlates with impaired gallbladder emptying.