Influence of Stress on Epithelial Cell Proliferation in the Gut Mucosa of Rats

Abstract

Wistar rats were stressed by immobilization in a cold environment during either 2 or 12 h. The animals were killed 1 h after intraperitoneal injection of 3H-thymidine and autoradiography was used. The proliferative parameters were estimated in the mucosa of the stomach after the 2-hour stress period. After the 12-hour stress period, labeling and mitotic indices were measured in the gastric mucosa as well as in the antrum, duodenum, ileum, colon and epidermis. The stress period of 2 h did not induce significant changes of the proliferative parameters in the mucosa of the stomach whereas cell proliferation was significantly inhibited in all examined tissues, including the skin, after the 12-hour stress period. Gastric hemorrhagic lesions were observed only in the oxyntic part of the stomach and occurred as early as 2 h after stress despite there was no change in the proliferative parameters at this time. The lesions became more obvious after the 12-hour stress period. Our observations indicate that inhibition of cell renewal by stress is not the mechanism by which stress erosions develop in the digestive mucosa.