The efficacy of angiotensin-converting enzyme inhibitors in preventing postoperative tendon adhesion formation: An experimental study in rats.

Abstract

The aim of this study was to investigate the efficacy of angiotensin-converting enzyme inhibitors (ACEIs) in preventing postoperative tendon adhesion formation in a rat model of Achilles tendon repair. In this study, 60 Sprague-Dawley male rats weighing 300 to 350 g were used. Rats were randomly divided into six groups (n = 10 per group): control-1, control-2, sham-1, sham-2, experiment-1, and experiment-2. The same surgical procedure was performed in all rats; a full thickness Achilles tenotomy was performed, and the tendon was repaired using a modified Kessler suture. Enalapril (10 mg/kg/day) was orally given to the Experiment-1 and Experiment-2 groups for three and six weeks, respectively. Thirty rats were sacrificed at three weeks (Control-1, Sham-1, Experiment-1); the remaining 30 rats were sacrificed at six weeks (Control-2, Sham-2, Experiment-2). Then, macroscopic, biomechanical, and histologic investigations were performed. Adhesion degree was found macroscopically lower in the Experiment-1 and 2 groups than others. In the histologic examination, the fibrosis level was found the lowest in the Experiment-2 group. Biomechanical evaluation indicated that mean maximum resistance before tendon rupture was significantly higher in the Experiment-2 group than in other groups. Evidence from this study has shown that ACEIs can decrease fibrosis and tendon adhesion during tendon recovery in rats due to their antifibrotic effects as the result of Angiotensin-II suppression.