PREDUODENAL MECHANISMS COMPENSATE COMPLETELY FOR ABSENT PANCREATIC-ENZYMES TO STIMULATE GALLBLADDER AFTER MEALS

We studied gallbladder emptying with gamma scintigraphy in nine dogs p repared with chronic pancreatic fistulas, so that pancreatic enzymes c ould be either completely excluded from the duodenum or supplied in no rmal amounts. During duodenal perfusion of the fasted dogs with fat em ulsions, gallbladder emptying was significantly less rapid when the em ulsion contained inactive vs active enzymes, confirming the potency of lipolytic products in the intestine as stimuli of gallbladder emptyin g. However, after feeding either a 115-g or a 460-g meal, each 18% fat , the gallbladders emptied identically whether or not pancreatic enzym es were excluded from the duodenum. We concluded that while products o f pancreatic lipolysis in the small intestine are potent stimuli of ga llbladder contraction, preduodenal mechanisms can compensate completel y for the absence of pancreatic hydrolysis in stimulating gallbladder emptying after a meal.