THE ROLE OF NITRIC OXIDE IN STRESS-INDUCED GASTRIC DAMAGE IN CHOLESTATIC RATS

In this study the effect of nitric oxide synthesis inhibition on stress-induced gastric damage was evaluated in bile duel ligated, sham operated and unoperated rats. Animals were injected intraperitoneally with NG-nitro-L-arginine methylester (L-NAME), 40 mglkg, L-argininc, 200 mg/kg or saline, 30 min before water-immersion stress. One hour after water immersion, the animals were killed and their stomachs were removed for measurement of gastric mucosal damage. Tfie results showed that L-NAME significantly enhances the development of gastric mucosal lesion in sham operated and unoperated rats, while in bile duct ligated animals, L-NAME decreases and L-arginine enhances the potentiation of stress-induced gastric mucosal damage. The results suggest that inhibition of nitric oxide synthase with L-NAME has different effects on stress-induced gastric damage in cholestatic rats compared with normal animals.