Susceptibility of various Helicobacter pyloris to New Antiulcer Agents

Helicobacter pylori (H. pylori) is a microaerophilic spiral bacterium and infection by it in the human stomach causes gastritis, furthermore, it is considered to be involved in the pathogenesis of peptic ulcers and the development of gastric carcinoma. We assessed the inhibitory activity of new antiulcer drugs against Helicobacter pylori. The activities of new antiulcer agents against Helicobacter pylori strains were determined by the standard agar dilution method with blood agar base #2, supplemented with 5% sheep blood and 4 antibiotics to support growth of these organisms. They were inoculated by multipoint inoculator and incubated at 37$^{\circ}C$ for 3 days under microaerophilic atmosphere. The MIC of antiulcer agents was the lowest concentration that inhibited visible growth of these organisms. According to results of various biochemical tests, these bacteria were identified as Helicobacter pylori strains. And the MIC results showed that the strains were very susceptible to omeprazole and YJA20379s. Some of YJA20379s were more potent than omeprazole. These results suggest that our new antiulcer drugs have potent inhibitory activity against Helicobacter pylori, so that our new antiulcer drugs might be useful for the clinical eradication of gastrointestinal Helicobacter pylori.