RESUMO
The aim of this study was to test the hypothesis that postconditioning (POC) would reduce the detrimental effects of the acute intestinal ischemia-reperfusion (I/R) compared to those of the abrupt onset of reperfusion. POC has a protective effect on intestinal I/R injury by inhibiting events in the early minutes of reperfusion in rats. Twenty-four Wistar-Albino rats were subjected to the occlusion of superior mesenteric artery for 30 minutes, then reperfused for 120 minutes, and randomized to the four different modalities of POC: (1) control (no intervention); (2) POC-3 (three cycles of 10 seconds of reperfusion-reocclusion, 1 minute total intervention); (3) POC-6 (six cycles of 10 seconds of reperfusion-reocclusion, 2 minutes total intervention); and (4) sham operation (laparotomy only). The arterial blood samples [0.3 mL total creatine kinase (CK) and 0.6 mL malondialdehyde (MDA)] and the intestinal mucosal MDA were collected from each after reperfusion. POC, especially POC-6, was effective in attenuating postischemic pathology by decreasing the intestinal tissue MDA levels, serum total CK activity, inflammation, and total histopathological injury scores. POC exerted a protective effect on the intestinal mucosa by reducing the mesenteric oxidant generation, lipid peroxidation, and neutrophil accumulation. The six-cycle algorithm demonstrated the best protection.