Morphology and chronology of ischemic mucosal changes in the small intestine. A light and electron microscopic investigation.

The morphology and chronology of an absolute ischemia was investigated on the small intestine of man and rat. It could be shown that the morphogenesis of ischemic damage to the intestinal mucosa in man does not differ from that in the rat. However, there are crucial and in therapeutic terms significant differences in the time course of the ischemic damage to the intestinal mucosa. Whereas in the small intestine of the rat, the first appreciable alterations - detachment and disruption of the lining epithelium at the villous tip - are already to be observed after absolute ischemia lasting 15 min, in the human small intestine the same lesions only occur after 4 h. A comparable complete necrosis of the small intestinal mucosa was detected in the rat after 7-h ischemia, and in man after 44-h ischemia.