Effect of the histamine-H2 antagonist cimetidine on meal-stimulated biliary secretion in dogs.

In conscious dogs with a bidirectional biliary cannula we studied the effect of orally administered cimetidine (10 mg/kg) on biliary secretion in response to a standard meal. The intake of a meal induced a significant increase in the biliary flow. When cimetidine is administered before feeding, a greater biliary response was observed in both cholecystectomized and uncholecystectomized animals. Under our experimental conditions this effect could be explained by an increase in the resistance of the sphincter of Oddi together with an increase in biliary tract and gallbladder motility. On the other hand, decrease in taurocholate and increase in chloride concentrations were observed during cimetidine treatment in all dogs. Moreover cimetidine elicits a fall in bilirubin concentration in cholecystectomized animals. The changes in organic anions could be due to a reduction in portal blood flow together with an interference of cimetidine with hepatic oxidative pathways. The greater concentration of chloride could be due to a lesser release of secretin. Most of these effects were transitory because they return to control values after the end of treatment.

Effect of the histamine-H2 antagonist cimetidine on meal-stimulated biliary secretion in dogs.

In conscious dogs with a bidirectional biliary cannula we studied the effect of orally administered cimetidine (10 mg/kg) on biliary secretion in response to a standard meal. The intake of a meal induced a significant increase in the biliary flow. When cimetidine is administered before feeding, a greater biliary response was observed in both cholecystectomized and uncholecystectomized animals. Under our experimental conditions this effect could be explained by an increase in the resistance of the sphincter of Oddi together with an increase in biliary tract and gallbladder motility. On the other hand, decrease in taurocholate and increase in chloride concentrations were observed during cimetidine treatment in all dogs. Moreover cimetidine elicits a fall in bilirubin concentration in cholecystectomized animals. The changes in organic anions could be due to a reduction in portal blood flow together with an interference of cimetidine with hepatic oxidative pathways. The greater concentration of chloride could be due to a lesser release of secretin. Most of these effects were transitory because they return to control values after the end of treatment.