ABSTRACT
Objective To search the feasibility of mutation,RdxA gene was analyzed by the metronidazole induction experiment.Method The non-multiple,sensitive H.pylori strains,were selected and subjected to metronidazole induction experiment,which made H.pylori strains transform susceptibility to resistance.Extracted DNA of metronidazole sensitive and resistant pairs of H.pylori strains before and after induced,amplified by PCR and sequenced rdxA gene.Result 4 of 12 H.pylori strains were induced successfully with metronidazole whose MICs increased by 16~64 times.Strains were transferred three times on metronidazole-free medium and the MICs redetermined were the same as those after induced.There was 0.2～0.8% difference between pairs of metronidazole sensitive and resistant H.pylori strains.There was 2.2～2.7% difference between unrelated H.pylori strains.Conclusion The metronidazole induction experiment could make H.pylori acquire stable resistance to metronidazole in a short period and exclude that the natural polymorphism of rdxA gene influenced on mutation analysis.There was good hope that the experiment would become a good method to research metronidazole resistance mechanism