We studied the effect of neurotensin, a hormone which increases the synthesis of DNA, RNA and protein in enterocytes blood flow and cellular proliferation in the small bowel mucosa of rats with intestinal ischemia reperfusion injury. Thirty rats were equally separated into three experimental groups: Group 1, explorative laparotomy; Group 2, 60 minutes of ischemia and 3 hours of reperfusion; Group 3, ischemia and reperfusion as in group 2 plus neurotensin 300 μg/kg/day IM. over 3 days. Levels of serum AST, ALT, CPK, LDH and tissue malondialdehyde (MDA) were measured. Histologic changes in intestinal mucosa were evaluated according to Chiu's classification. Mean serum levels of measured enzymes were significantly lower in group 3 than in group 2. Tissue levels of MDA, which is a product of lipid peroxidation, were 1.54 nmol/mg protein in group 2 and 1.10 nmol/mg in group 3 (p=0.001). According to Chiu's classification, histologic examination revealed significantly less mucosal damage in group 3 than group 2; 2.6 versus 3.8 (p=0.009). These findings suggest that neurotensin has a protective effect on intestinal ischemia reperfusion injury in rats.