HEALING OF COLONIC ISCHEMIC ANASTOMOSES IN THE RAT - ROLE OF SUPEROXIDE RADICALS

PURPOSE: The aim of this study was to evaluate the role of superoxide radicals in the healing of ischemic colonic anastomoses in the rat. ME THODS: Adult male Wistar rats were used in a factorial design with two factors (normal or ischemic colonic anastomoses) each having two leve ls (treatment with saline or allopurinol). Colonic anastomoses were pe rformed either in normal or previously devascularized colons (ischemic anastomoses) at identical locations, using the same technique. On the fourth postoperative dag, animals were killed, and specimens were tak en for determinations. RESULTS: Ischemic anastomoses displayed signifi cant increases in superoxide radical (assayed as superoxide anion), su peroxide dismutase, and glutathione peroxidase concentrations. Burstin g strength and hydroxyproline levels were also significantly lower in these anastomoses. Allopurinol administration elicited a significant d ecrease in superoxide anions and raised both bursting strength and hyd roxyproline levels only in ischemic anastomoses. CONCLUSIONS: Superoxi de radicals are involved in the delay in healing of ischemic anastomos es. Allopurinol lowers superoxide anion production and has beneficial effects on the cicatrization of ischemic anastomoses.