A STUDY OF INTESTINAL DYSFUNCTION INDUCED BY RESTRAINT STRESS IN RATS

Background: The pathogenesis of intestinal dysfunction induced by stre ss has not been established. We tried to clarify possible causal mecha nisms of irritable bowel syndrome. Methods: An experimental model of i ntestinal dysfunction was designed using loading restraint stress in r ats. A cannula was inserted into the origin of the duodenum or colon, with the other end leading to the skin. To provide intestinal content, a semi-solid colored marker was used for monitoring intestinal transi t. After 1 week the marker was injected into the intestine through the cannula under unanesthetized wakefulness. Results: Under restraint st ress, transit in the small intestine was suppressed, but actual suppre ssion took place only in the upper half, where the contents normally m oved fast. Transit time in the colon was reduced by restraint stress. This reduction was attributed to the disappearance of the stagnant reg ion, which was present under normal conditions. Conclusions: These res ults suggested that restraint stress affects the function of the pacem aker site of the intestine.