Comparative studies of the effects of fasting on bile salt pool sizes of hamsters and rats.

Comparative studies of the effects of fasting on the total bile salt pool sizes of intact and cholecystectomized hamsters and rats were made. Rats, a species which has no gallbladder, are able to maintain the size of their total bile salt pool during 24, 48 and 72 hour fasts by an undetermined effective mechanism. Intact hamsters fasted 24, 48 and 72 hrs maintained and even increased the size of their bile salt pool. Bile salt conservation was effected by storage of the salts in the gallbladder, and to some extent, the small intestine. Cholecystectomized hamsters apparently lack any mechanism to effect bile salt conservation during fasting since their bile salt pool size decreased precipitously during 24 and 48 hr fasts.