Small bowel motility and colonic transit are altered in dogs with moderate renal failure.

Although gastrointestinal complications are common in patients with renal disease, the effects of renal dysfunction on bowel motility and gut transit times are not well known. We assessed gastrointestinal electromyographic activity, gastric emptying rate, orocolonic transit time, oroanal transit time, and xylose absorption before and after surgically inducing a 66% decrease in glomerular filtration rate in dogs. Moderate renal failure induced no gross or microscopic gastrointestinal lesions but caused a 16-42% increase in gastrointestinal motility indexes. We found a 24% decrease in the propagation velocity of the myoelectrical migrating complex in the duodenojejunal segment, a 30% decrease in phase I duration in duodenal and jejunal regions, a 20% increase in the total irregular electrical activity of the small intestine, and a 22% increase in duration of the meal response in the duodenum and jejunum. Renal failure did not change xylose absorption, gastric emptying rate, and orocolonic transit time but decreased colonic transit time by 38%. The mean weight of feces was increased. These results indicate that moderate renal failure alters duodenojejunal motility and decreases colonic transit time.