Comparison of the effects of Nintedanib and Colchicine on peritoneal adhesion development in rats

Peritoneal adhesions remain a frequent complication after abdominal surgery and may lead to intestinal obstruction, chronic pelvic pain, and infertility. This experimental study compared the effects of colchicine and nintedanib on adhesion formation in a standardized rat cecal abrasion model. Thirty-two male Wistar Albino rats were randomized into four groups: sham, isotonic saline, colchicine, and nintedanib. Colchicine was administered orally at 0.5 mg/kg/day for 14 days, whereas nintedanib was given as a single intraperitoneal dose of 50 mg/kg. Adhesions were evaluated on day 14 using Nair scoring, six- region anatomical mapping, and histopathological grading of fibrosis, inflammation, edema, and lymphoid nodule involvement. Statistical analyses included the Kruskal-Wallis test with Dunn's post-hoc analysis and the Fisher-Freeman-Halton exact test where appropriate. No adhesions developed in the colchicine or isotonic saline groups. Sham animals developed localized central adhesions, whereas the nintedanib group showed adhesions across multiple anatomical regions. Total adhesion scores differed significantly among groups (P = 0.018, η² = 0.34). Fibrosis and inflammation scores were significantly higher in the nintedanib group (P = 0.014, η² = 0.35 and P = 0.008, η² = 0.39, respectively), and edema scores also differed significantly (P=0.022, η²=0.32). After Bonferroni correction, only central region adhesions remained significant (P < 0.001). Colchicine effectively prevented peritoneal adhesion formation in this model, whereas intraperitoneal nintedanib increased fibrotic and inflammatory responses. These findings suggest that route of administration and formulation are critical determinants of therapeutic efficacy in adhesion prevention.