Effects of cholesterol gallstone induction on gallbladder function and bile salt pool size in the prairie dog model.

The prairie dog gallstone model was used to test the following hypotheses: (1) gallbladder stasis occurs in association with gallstone formation, and (2) bile salt pool size decreases as gallstones develop. Bile salt pool sizes and the extent of equilibration of hepatic and gallbladder bile salt over the course of gallstone development were measured. No evidence for bile salt pool reduction was found, but there was significant evidence of progressively inefficient equilibration of hepatic and gallbladder bile salt very early during gallstone formation. These changes, suggestive of gallbladder stasis and observed only in the presence of cholesterol crystals in bile, persisted as cholesterol stones developed and antedated any reduction in bile salt pool size.