Gastrointestinal changes in the rat on realimentation.

Abstract

Forty-eight male rats were divided into equal groups by pairing as regards body weight. One group of 24 were injected subcutaneously 14 hours after the withdrawal of food with C14-l-histidine; the second group was not injected. Twelve rats in each group were fasted for 72 hours and twelve others were fasted for 48 hours and then fed for 24 hours. At 72 hours the wet and dry weight of the entire glandular stomach and small intestine was determined separately, and the C14-histamine in each of those which had received C14-l-histidine was determined. Realimentation for 24 hours increased the wet and dry weight of the stomach by 15% and 13%, respectively, and of the intestine by 58% and 40%, respectively. Therefore, after 48 hours of fasting realimentation for 24 hours affects the composition of the intestine more than the stomach. Twenty-four hours of realimentation reduced the C14-histamine content of the stomach by 58% and of the intestine by 30%. It was found by calculation that a maximum of only 10% of the C14-histamine lost from the stomach and 30% from the intestine could be accounted for by desquamation of superficial cells. The rate of loss and renewal of superficial cells in the intestine during 24 hours of realimentation after 48 hours of fasting was approximately three times faster than that in the stomach.