An FDA Approved Neurokinin-1 Receptor Antagonist is Effective in Reducing Intraabdominal Adhesions when Administered Intraperitoneally, But Not Orally

Introduction Postoperative adhesions pose a continued healthcare problem. We previously demonstrated that intraperitoneal (IP) administration of a neurokinin-1 receptor antagonist (NK-1RA) at surgery reduces intraabdominal adhesions in rats. The NK-1RA aprepitant (Emend™, Merck) is clinically approved for preventing postoperative nausea and vomiting; however, its effects on adhesion formation are unknown. Thus, we determined the effects of IP and oral administration of aprepitant on adhesion formation in a rat model. Methods Adhesions were surgically induced in rats that were randomized to receive either one or five oral preoperative doses or a single intraoperative IP dose of aprepitant (50 mg/kg). Adhesions were scored at 7 days. In similar experiments using IP dosing, animals were sacrificed at 24 h and peritoneal fluid, and tissue were collected to assess fibrinolytic activity and tissue plasminogen activator (tPA) and plasminogen activator inhibitor-1 (PAI-1) mRNA levels, respectively. Results IP aprepitant reduced adhesion formation by 33% ( p