Role of Reactive Oxygen Metabolites in the Genesis of Helicobacter Pylori Associated Gastric Ulcer

Rew, Jong Sun; Lee, Wan Sik; Seo, Young Ho; Seo, Kang Seok; Joo, Young Eun; Kim, Hyun Soo; Choi, Sung Kyu; Suh, Soon Pal; Kim, Sei Jong

Abstract

The aim of this study was to assess the role of reactive oxygen metabolites (ROMs) in Helicobacter Pylori (H. pylori)-associated gastric ulcer. Twenty seven patients with gastric ulcer (22 H. pylori-positive and 5 H. pylori-negative) were entered study. Production of ROMs in antral mucosa and ulcer margin was assessed by measuring myeloperoxidase (MPO) activity and malondialdehyde (MDA) produced by lipid peroxidation. ROMs production was compared on the basis of H. pylori-positivity, degree of neutrophilic infiltration, and treatment modality (Group I ; ranitidine alone, Group II ; ranitidine plus rebamipide). Significant differences were observed in the pretreatment concentrations of MPO and MDA between ulcer margin and antral mucosa (103. 1 vs 34.4 U/mg protein in MPO, p<0.01 ; 133.2 vs 16.7 nmol of MDA /mg protein, p<0.05). MPO activity was significantly increased in H. pylori-positive gastric micosa compared with that of H. pylori-negative gastric mucosa (126.8 vs 40.8 U/mg protein; p<0.01). However, there was no significant correlation between the degree of infection load of H. pylori and the production of ROMs. Concentration of MDA in the gastric mucosa was not affected by H. pylori-positivity. Combined ranitidine and rebamipide treatment significnntly reduced th MPO activity in the ulcer margin in comparsion with the treatment by ranitidine alone (p<0.01). However, the MDA production was not affected by the treatment modality. In conclusion, the alterations in the production of ROMs found in H. pylori-associated gastric ulcer may not directly related to the pathogenesis of the ulcer.