Age-associated gallstone formation in male and female CCK-1(A) receptor-deficient mice

Background. Gallbladder dysmotility accelerates cholelithiasis. In turn, gallbladder dysmotility can occur secondary to inflammation and excess cholesterol accumulation in gallbladder smooth muscle. Methods. The present study was designed to determine how much gallbladder dysmotility contributes to gallstone formation as a primary cause and whether a sex difference exists in gallstone formation by comparing cholecystokinin-1 receptor gene-deficient [CCK-1R(-/-)] male and female mice. Results. No sludge or gallstone formation was observed in mice at 6 months of age. The frequency of sludge and gallstone formation in mice at 12 and 24 months of age was slightly higher in female CCK-IR(-/-) mice than in males, but the difference was not significant. Conclusions. Gallbladder dysmotility may have accelerated sludge and gallstone formation, but its contribution was limited. A 12-month period was required to produce gallstones, and after the mice reached 12 months of age, further ageing did not increase the frequency of gallstones. The effect of sex did not reach a significant level.