COLONIC HEALING AFTER EARLY INTRAPERITONEAL ADMINISTRATION OF 5-FLUOROURACIL AND INTERFERON IN RATS

The aim of this experimental study was to investigate whether the intr aperitoneal perioperative injection of 5-flurouracil (5-FU) - with or without the addition of interferon (INT) - influences colonic healing. We used 57 male Wistar rats which were subjected to anastomosis of th e colon. Intraoperatively, the rats were randomised into one of three groups. The rats in the control group (group 1, n = 15) received a 0.9 % NaCl solution; the rats in group 2 (n = 21), 5-FU (20 mg/Kg/day), an d those in group 3 (n = 21), 5-FU (20 mg/Kg/day) plus INT (45.000 IU/K g/day), These drugs were injected intraperitoneally during the operati on and once daily for the next two days. The rats were sacrificed on p ost-operative days 3, 5 or 8. The rupture rate of the anastomoses was statistically significantly higher in groups 2 and 3 compared with the control group (P < 0.05); no differences were observed between groups 2 and 3. Abscess and adhesion formation were more marked in groups 2 and 3 than in the control group; however no differences were recorded between groups 2 and 3. The anastomotic bursting pressure was statisti cally significantly lower in groups 2 and 3 compared to the control gr oup (P < 0.05). On post-operative days 5 and 8; however, no difference s were measured between groups 2 and 3. Histologic evaluation also sho wed a more profound inflammatory response in groups 2 and 3, compared with group 1. In conclusion, the intraperitoneal, intraoperative admin istration of 5-FU hinders colonic healing in rats. The additional intr aperitoneal injection of interferon does not seem to aggravate this ad verse effect.