The Early Gastrointestinal Response in the Rat Exposed to Whole-Body X-Irradiation

Abstract

Fasting rats were exposed to whole-body x irradiation at doses of 100, 300, 500, and 700 r. Immediately prior to fasting, charcoal was incorporated into the diet in order to locate the food along the intestinai tract. During the first 5 hours post-irradiation, the weight of the stomach contents in all groups increased. At the same time the movement of the carbon particles indicated that there was an antiperistalsis in the small intestine that caused the intestinal contents to be regurgitated into the stomach. An analogy between this response and the radiation sickness in human subjects is made, and a hypothesis accounting for this is proposed.