Establishment of Helicobacter pylori infection model and influence of its infection on N-methyl-N-~nitrosourea -induced gastric carcinogenesis in Balb/c mice / 中华消化杂志

ABSTRACT

Objective To establish a new Helicobacter pylori(H.pylori) infection model which is more stable and to find the relationship between H. ~pylori infection and gastric carcinogenesis induced by nitrosourea. Methods A total of 94 Balb/c mice were divided into four groups. Two groups of mice were inoculated with H.pylori, among which one group of mice received continuous N-methyl-N-nitrosourea(MNU) administration via the drinking water. The third group were only given MNU, and the forth as control. After 36 weeks, all the mice were ~sacrificed . The infection of H.pylori in gastric mucosa of the mice was analyzed by rapid urease test, ~Giemsa staining and culture. The histopathological changes in the gastric mucosa of mice were assessed in ~H-E stained sections. Results The total infection rate of H.~pylori in Balb/c mice was 93.9%. All the mice in group with H.pylori infection alone had chronic gastritis, in which 20.0% was atrophic gastritis. In the group of mice with H.pylori infection and MNU intake, all had chronic gastritis, and among them 23.1% had atrophic gastritis, 42.3% corpus dysplasia and 57.7% antrum dysplasia. In this group, two mice (7.1%) with low differentiated adenocarcinoma were found. Compared with control group, two groups with H. ~pylori infection only and H. ~pylori plus MNU intake reached statistical difference in the view of inflammatory latitude (P