Role of nitric oxide in gastric injury induced by hemorrhagic shock in rats

The aim of this study was to investigate the effect of nitric oxide (NO) on the gastric injury induced by hemorrhagic shock. Hemorrhagic shock was cre ated by withdrawing 3 ml blood/200 g body weight of the rats. Before the he morrhage, N-G-nitro-L-arginine methyl ester (L-NAME, 10 mg/kg i.v. bolus), D-NAME (10 mg/kg i.v. bolus), or L-arginine (100 mg/kg i.v. bolus and 10 mg /kg/min infusion) + L-NAME were administered. At the end of the 1-hour hypo volemic shock period, histological analysis, gastric ulcer index, gastric m yeloperoxidase (MPO) activity, and gastric protein oxidation (PO) levels we re determined. In histological analysis a destructive effect of L-NAME (NO synthase inhibitor) was demonstrated. L-NAME treatment increased gastric MP O activity, L-arginine reversed this effect and D-NAME had no effect. Tissu e PO activity was found to be increased in L-NAME-treated rats; L-arginine treatment reversed this activity. It is concluded that gastric barrier func tion is altered after hemorrhagic shock, and L-arginine (NO precursor) can prevent mucosal injury in the stomach. This effect of NO may be on gastric blood flow and can be mediated by tissue neutrophils. Copyright (C) 2000 S. Karger AG, Basel.