The time sequence of injury and recovery following transient reversible intestinal ischemia

Intestinal mucosal damage and regeneration were examined in rats following transient ischemia produced by the occlusion of the superior mesenteric artery for 30 min. Animal groups were assigned for harvesting of small bowel specimens at 10, 17, and 30 min and 1, 2, 3, 4, 6, 12, and 24 hr post-relief of ischemia. Severe damage to the villi was evident already at 10 min postischemia. Thereafter a very rapid restitutional process was observed with restoration of villi epithelium in 47.6% of the examined animals at 60 min, 75% at 4 hr, and 100% at 12 hr. This rapid sequence of events should be taken into consideration when designing experimental ischemic bowel animal models and possible therapeutic modalities.