Response of blood endothelin-1 and nitric oxide activity in duodenal ulcer patients undergoing Helicobacter pylori eradication

AIM: To investigate the effect of Helicobacter pylori eradication on endothelin-1 (ET-1) and nitric oxide (NO) in duodenal ulcer (DU) patients. METHODS: Sixty-six H pylori-infected active DU patients were consecutively enrolled to receive one-week triple therapy (rabeprazole, amoxicillin and metronidazole) and then one-month rabeprazole therapy. They were asked back to determine ulcer and H pylori status using endoscopy one month later. Thirty-seven healthy controls (H pylori +/-: 17/20) were enrolled for comparison. Blood samples were collected in each visit to measure plasma ET-1 and nitrate/nitrite levels using an enzyme immunoassay kit. RESULTS: Sixty DU patients finished trial per protocol. The ulcer healing and H pylori-eradication rates were 86.7% and 83.3%, respectively. Plasma ET-1 level in DU patients was higher than that of H pylori-negative and positive controls (3.59+/-0.96 vs 0.89+/-0.54 vs 0.3+/-0.2 pg/mL, P<0.01), while nitrate/nitrite levels among them were also significantly different (8.55+/-0.71 vs 5.27+/-0.68 vs 6.39+/-0.92 mumol/L, P<0.05). H pylori eradication diminished ET-1 levels (3.64+/-0.55 vs 2.64+/-0.55 pg/mL, P<0.01) but elevated nitrate/nitrite level (8.16+/-0.84 vs 11.41+/-1.42 mumol/L, P<0.05). CONCLUSION: Both plasma ET-1 and nitrate/nitrite levels increase in active DU patients. After an effective H pylori eradication, DU healing is associated with diminished blood ET-1 level and elevated nitrate/nitrite level.