Influence of in situ neural isolation of jejunoileum on postprandial pancreatobiliary secretion and gastric emptying

Our aims were to examine the influence of neural isolation of the jejunoileum on opstprandial pancreatobiliary secretion. In four dogs, duodenal perfusion and aspiration catheters were implanted, and serosal electrodes were placed along the proximal small bowel. Control studies of gastric emptying output of bile acids and amylase, and plasma concentrations of peptide YY and neurotensin were performed on three occasions following ingestion of a 340-kcal mixed-nutrient liquid meal. The dogs then underwent our model of in situ jejunoileal neural isolation, and the meal studies were repeated. Neural isolation, when compared to control, did not affect either postprandial conversion of intestinal myoelectric activity to the "fed" pattern, gastric emptying (T1/2,X±se of the liquid meal (74±6 vs 79±7 min;P>0.05), or cumulative amylase output (373±59 vs 305±66 kU;P>0.05). Neural isolation decreased cumulative postprandial bile acid output from 6.6±0.9 mM to 3.4±1.1 mM (P<0.05) and increased postprandial plasma concentrations of peptide YY and neurotensin. Our findings suggest that the jejunoileal denervation that accompanies the in situ neural isolation of the jejunoileum is not associated with changes in postprandial motility patterns, gastric emptying, or pancreatic amylase secretion. Loss of this innervation, however, may decrease postprandial output of bile acids and lead to a compensatory increase in the postprandial release of neurotensin and peptide YY.