Gastric emptying and small intestinal mucosal injury in rats.

A technique was developed to produce small intestinal mucosal injury in vivo by perfusing the mid-small intestine of rats with HCl, NaOH, FeSO4, and AgNO3. Three hours following injury, gastric emptying and small intestinal transit were measured by examining the gastrointestinal distribution of a non-absorbable radioisotope which had been placed in the stomach for 1 hour. There was a strong association between the villus injury produced by various concentrations of the injurious agents and the degree of gastric retention. Necrosis of villus tips, as produced by AgNO3, was sufficient to cause marked gastric retention. Injury to the small intestinal mucosa of one parabiotic rat did not produce gastric retention in the partner. It is concluded that injury to small intestinal villi is sufficient to induce gastric retention and that the effect is most likely nerve-mediated.