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

The aim of this study was to evaluate the role of neutrophil activation dur ing 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 4 rats. 14 days later, the animals underwent a second la parotomy. After the adhesion formations were evaluated, adhesion bands adhe red to the peritoneal defect were excised, together with normal tissue 1 cm from the adhesion band. Myeloperoxidase and elastase activities were deter mined in peritoneal tissue samples excised during the first laparotomy (con trol group), adhesion bands adhered to the peritoneal defect (adhesion grou p) 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 nor mal peritoneum group (P < 0.001). Elastase activity in the adhesion group w as significantly higher than in the control group (P < 0.001). The normal p eritoneum group elastase activity was significantly higher than in the cont rol group (P < 0.001), but significantly lower than in the adhesion group ( P < 0.001). The increased activities of neutrophil activation markers in no rmal peritoneum tissues may suggest that the inflammatory reaction was not limited to the adhered peritoneum. The role of elastase inhibitors in preve nting peritoneal adhesion should be determined in further studies. Med Sci Res 27:631-633 (C) 1999 Lippincott Williams & Wilkins.