H Pylori
Copyright ©The Author(s) 2004. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. Mar 15, 2004; 10(6): 852-855
Published online Mar 15, 2004. doi: 10.3748/wjg.v10.i6.852
Establishment of Helicobacter pylori infection model in Mongolian gerbils
Jie Yan, Yi-Hui Luo, Ya-Fei Mao
Jie Yan, Yi-Hui Luo, Ya-Fei Mao, Department of Medical Microbiology and Parasitology, College of Medical Science, Zhejiang University, Hangzhou 310031, China
Author contributions: All authors contributed equally to the work.
Supported by the Excellent Young Teacher Fund of Chinese Education Ministry and the General Research Plan of the Science and Technology Department of Zhejiang Province, No. 001110438
Correspondence to: Jie Yan, Department of Medical Microbiology and Parasitology, College of Medical Science, Zhejiang University, 353 Yan an Road, Hangzhou 310031, Zhejiang Province, China. yanchen@mail.hz.zj.cn
Telephone: +86-571-87217385 Fax: +86-571-87217044
Received: September 15, 2003
Revised: September 23, 2003
Accepted: November 13, 2003
Published online: March 15, 2004
Abstract

AIM: To establish a stable and reliable model of Helicobacter pylori infection model in Mongolian gerbils and to observe pathological changes in gastric mucosa in infected animals.

METHODS: Mongolian gerbils were randomly divided into 18 groups; 6 groups were infected with H pylori clinical strain Y06 (n = 6, groups Y), 6 groups were infected with H pylori strain NCTC11637 (n = 6, groups N), and 6 uninfected groups as negative controls (n = 4, groups C). H pylori suspensions at the concentrations of 2 × 108 and 2 × 109 CFU/mL of strain NCTC11637 and strain Y06 were prepared. The animals in three groups N and in three groups Y were orally challenged once with 0.5 mL of the low concentration of the bacterial suspension. The animals in another three groups N and in another three groups Y were orally challenged with 0.5 mL of the high concentration of the bacterial suspension for 3 times at the intervals of 24 h, respectively. For the negative controls, the animals in six groups C were orally given with the same volume of Brucella broth at the corresponding inoculating time. The animals were killed after 2nd, 4th and 6th week after the last challenge and the gastric mucosal specimens were taken for urease test, bacterial isolation, pathological and immunohistochemical examinations.

RESULTS: Positive isolation rates of H pylori in the animals of groups Y at the 2nd, 4th and 6th week after one challenge were 0%, 16.7% and 66.7%, while in the animals of groups N were 0%, 0% and 16.7%, respectively. Positive isolation rates of H pylori in the animals of groups Y at the 2nd, 4th and 6th week after three challenges were 66.7%, 100% and 100%, while in the animals of groups N were 66.7%, 66.7% and 100%, respectively. In animals with positive isolation of H pylori, the bacterium was found to colonized on the surface of gastric mucosal cells and in the gastric pits, and the gastric mucosal lamina propria was infiltrated with inflammatory cells.

CONCLUSION: By using H pylori suspension at high concentration of 2 × 109 CFU/mL for multiple times, the orally challenged Mongolian gerbils can be used as a stable and reliable H pylori infection model. The 2 strains of H pylori can colonize in gastric mucosa of the infected animals and cause mild inflammation reaction.

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