Abstract
Background Inducible nitric oxide synthase (iNOS) has a significant role in ischemia reperfusion (I-R) injury. I-R injury impairs the healing at the intestinal anastomotic site. This study was designed to assess the role of aminoguanidine (AG, a selective inhibitor of iNOS), in healing at the colonic anastomotic site after intestinal I-R injury in rats.
Methods Female Wistar rats (n = 60) were divided into three groups. Group I (n = 15): sham operation, Group II (n = 15): I-R injury and anastomosis, and Group III (n = 30): I-R injury + anastomosis + AG-50 mg/kg. On the 7th postoperative day, relaparotomy was done and 4 cm of the colon with an intact area of the anastomosis was resected. Bursting pressure and histology at the anastomotic site were assessed.
Results The bursting pressure was significantly higher in Group III. In addition, bridging parameters (i.e., mucosal continuity, muscular continuity, re-epithelization, and granulation tissue), collagen pattern, and collagen density were significantly better in Group III. While the polymorphonuclear density was higher in Group II, suggestive of delayed healing.
Conclusion AG, by decreasing inflammation and increasing collagen content in an organized pattern, helped in preventing I-R injury at the site of colonic anastomosis in rats.
Keywords
ischemia reperfusion injury - nitric oxide synthase - aminoguanidine - intestinal anastomosis healing