Effect of enteric pacing on intestinal motility and hormone secretion in dogs with short bowel.
The present study was designed to examine the role of electrode position during retrograde pacing in dogs with short bowel syndrome and unsevered intact duodenum. In nine beagle dogs a subtotal resection of the small bowel and jejunoileostomy was performed. In five of these dogs, an isolated blind loop (jejunum) with preserved mesenteric connections was left in situ as an additional place for a stimulation electrode. Small intestinal motility and plasma levels of insulin, glucagon, gastrin, somatostatin, and glucose were examined during pacing of the residual jejunum or the isolated loop, respectively, compared with control experiments in the same dogs without pacing. During pacing of the loop a significant (P less than 0.05-0.01) decrease in the postprandial small intestinal motility index was observed combined with a significant (P less than 0.05) increase in plasma insulin levels, whereas the postprandial increase in glucagon, somatostatin, gastrin, and glucose levels was not different from that in controls. In contrast, pacing of the jejunum increased postprandial small intestinal motility index (less than or equal to 68%), whereas the levels of the four hormones and plasma glucose were not different from those in controls. The data suggest that in dogs with intact duodenum, pacing on an excluded loop is required to obtain the desired effect of reduced intestinal motility and improved anabolic pancreatic hormone secretion.