The effects of verapamil vs. allopurinol on intestinal ischemia/reperfusion injury in rats. "An experimental study"

Although studies have reported that xanthine oxidase inhibitors or calcium channel blockers attenuate the ischemia-reperfusion injury in several organ systems, no comparative study exists on the significance of each of these pathways. To study this, in anesthetized Wistar Albino rats, a surgical model for intestinal ischemia-reperfusion injury was employed.

In experimental animals, after laparotomy, the superior mesenteric artery was occluded for 30 min, followed by a 2-h period of reperfusion; control rats underwent only a sham laparotomy procedure. One group of experimental animals was pretreated intraperitoneally with the calcium channel blocker verapamil (0.3 mg/kg), another group with the xanthine oxidase inhibitor allopurinol (100 mg/kg), the third group received no pretreatment. Plasma lactate, malondialdehyde and glutathione levels as well as intestinal tissue malondialdehyde and glutathione levels were measured to assess for possible protective effects. Histologic evaluation of the extent of injury was also performed.

Irreversible tissue damage was depicted in the untreated group, and partially in the allopurinol pretreatment group by histologic examination. Ischemia-reperfusion injury was reversible in the verapamil group. The laboratory results also supported these findings.

Protective effects of verapamil on ischemia-reperfusion injury have been found to be significantly (p<0.0001) more effective compared to allopurinol.