The effect of iNOS inhibitors and hyperbaric oxygen treatment in a rat model of experimental colitis.

Aim: Our aim was to investigate the effectiveness of aminoguanidine (AMG), an inducible nitric oxide synthase inhibitor, and hyperbaric oxygen (HBO) treatment in an experimental colitis model.

Methods: We induced colitis in rats. In the control group, we applied 2 ml serum physiologic intraperitoneally for 7 days. In the HBO group, 100% oxygen at 2.4 atm pressure was applied for 7 days. In the AMG group, 100 mg/kg AMG was applied intraperitoneally for 7 days. In the HBO + AMG group, HBO and AMG were applied, respectively. At the end of 7 days, rats were sacrificed and the distal 10 cm part of colon was examined macro- and microscopically.

Results: Severity of colitis and NO activities were reduced by AMG, HBO, and HBO + AMG application. There was histologically significant improvement, especially in the HBO + AMG group.

Conclusions: Both HBO and AMG were significantly effective in preventing weight loss, reducing NO activities, and severity of colitis, when comparing HBO and AMG separately.