ENHANCEMENT OF PERITONEAL-MACROPHAGES REDUCES POSTOPERATIVE PERITONEAL ADHESION FORMATION

Postoperative adhesion formation results from a fibroproliferative inf lammatory reaction. Macrophages are critical in the final resolution o f the inflammatory process and tissue repair, including modulation of proliferation and differentiation of fibroblasts and secretion of neut ral proteases like plasminogen activator. We, therefore, studied the i nfluence of peritoneal macrophage enhancement on postoperative adhesio n formation in five groups of rabbits. Group 1 was a control with norm al peritoneum. Animals in group 2 had increased macrophage population in their peritoneum by intraperitoneal injection of protease peptone 3 days before adhesion induction. In group 3, animals were treated by p rotease peptone as in group 2 and then depleted of the increased macro phage population by peritoneal lavage before adhesion induction. In gr oup 4 macrophages were transplanted from animals enriched as in group 2 into a nonenriched peritoneum at the time of adhesion induction. Gro up 5 had a normal peritoneum with peritoneal lavage before adhesion in duction. Peritoneal adhesions were induced at laparotomy by repairing a peritoneal defect in two different models. It was found that enhance ment of peritoenal macrophages by protease peptone reduced markedly th e degree of postoperative adhesion formation. After depletion of the e nhanced peritoneal macrophages by peritoneal lavage the degree of adhe sion formation was equivalent to that of controls. Finally, macrophage transplantation into a nonenhanced macrophage peritoneum also reduced the degree of postoperative adhesion formation. It is concluded that enhancement of peritoneal macrophages reduces postoperative peritoneal adhesion formation. (C) 1995 Academic Press, Inc.