title: Histopathological changes at colonic anastomotic site after ischemia reperfusion injury: role of aminoguanidine in experimental model.
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.
  
  
  CONCLUSIONS
  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.
authors.affiliation: Department of Pediatric Surgery, All India Institute of Medical Sciences, New Delhi, India.
authors.forename: Shailesh
authors.initials: S
authors.lastname: Solanki
authors.affiliation: Department of Pediatric Surgery, All India Institute of Medical Sciences, New Delhi, India.
authors.forename: M
authors.initials: M
authors.lastname: Srinivas
authors.affiliation: Department of Pediatric Surgery, All India Institute of Medical Sciences, New Delhi, India.
authors.forename: Anand
authors.initials: A
authors.lastname: Sinha
authors.affiliation: Department of Pediatric Surgery, All India Institute of Medical Sciences, New Delhi, India.
authors.forename: Deepak
authors.initials: D
authors.lastname: Mittal
authors.affiliation: Department of Pathology, All India Institute of Medical Sciences, New Delhi, India.
authors.forename: Saumyaranjan
authors.initials: S
authors.lastname: Mallick
authors.affiliation: Department of Pediatric Surgery, All India Institute of Medical Sciences, New Delhi, India.
authors.forename: Sandeep
authors.initials: S
authors.lastname: Agarwala
authors.affiliation: Department of Pediatric Surgery, All India Institute of Medical Sciences, New Delhi, India.
authors.forename: V
authors.initials: V
authors.lastname: Bhatnagar
mesh_terms: D000714:Anastomosis, Surgical; D000818:Animals; D003094:Collagen / Q000096:biosynthesis; D003106:Colon / Q000473:pathology* / Q000601:surgery; D005260:Female; D006146:Guanidines / Q000494:pharmacology*; D006801:Humans; D007413:Intestinal Mucosa / Q000473:pathology; D023421:Models, Animal; D052247:Nitric Oxide Synthase Type II / Q000037:antagonists & inhibitors*; D017208:Rats, Wistar; D015427:Reperfusion Injury / Q000473:pathology* / Q000503:physiopathology / Q000517:prevention & control; D013718:Tensile Strength; D014945:Wound Healing / Q000187:drug effects*
chemical_list: D006146:Guanidines; D003094:Collagen; D052247:Nitric Oxide Synthase Type II; C004479:pimagedine