Pathologic changes in the glandular stomach and duodenum in an H. pylori-infected Mongolian gerbil model.

We have established a Helicobacter pylori-infected Mongolian gerbil model following Hirayama's method to investigate gastric diseases associated with H. pylori infection. We orally administered the culture broth of H. pylori ATCC 43504 to 8-week-old male Mongolian gerbils. After this, the gerbils were fed in a vinyl isolator. Subsequently, over the course of 48 weeks some of them were sacrificed for histopathologic examination and H. pylori culture. H. pylori colonization in the glandular stomach was seen in all the infected gerbils but only a few H. pylori were detected histologically. Acute inflammation, immature epithelium, and erosion were observed 2 weeks after H. pylori infection. Chronic inflammation was noted from 4 weeks after H. pylori infection. In addition, we found intestinal metaplasia and gastric ulcers from 12 and 24 weeks, respectively. There was mild to moderate inflammation in the duodenum but no ulcerative lesions or gastric metaplasia were observed. Some histologic findings were similar to those in humans, but inflammation occurred mainly in the deep mucosa and submucosa. This is a good animal model for H. pylori-associated gastric diseases but not for duodenal ulcers or gastric metaplasia. It might be useful for investigating the pathogenesis of H. pylori infection in the stomach.