Role of neutrophil activation in post-operative adhesion formation in a rat model: Increased myeloperoxidase and elastase activities

Abstract

The aim of this study was to evaluate the role of neutrophil activation during adhesion formation in rat peritoneal adhesion model. A 1 x 1 cm area of peritoneum and transversus abdominal muscle was removed on the right lower abdominal wall of 14 rats. 14 days later, the animals underwent a second laparotomy. After the adhesion formations were evaluated, adhesion bands adhered to the peritoneal defect were excised, together with normal tissue 1 cm from the adhesion band. Myeloperoxidase and elastase activities were determined in peritoneal tissue samples excised during the first laparotomy (control group, adhesion bands adhered to the peritoneal defect (adhesion group) and peritoneal tissue excised during the second laparotomy 1 cm from the peritoneal defect (normal peritoneum group). Myeloperoxidase activity was significantly higher in the adhesion group that in both the control and normal peritoneum group (P < 0.001). Elastase activity in the adhesion significantly higher than in the control group (P < 0.001). The normal peritoneum group elastase activity was significantly higher than in the control group (P < 0.001), but significantly lower than in the adhesion group (P < 0.001). The increased activities of neutrophil activation markers in normal peritoneum tissues may suggest that the inflammatory reaction was not limited to the adhered peritoneum. The role of elastase inhibitors in preventing peritoneal adhesion should be determined in further studies.