Expression data from stomach of germ-free and gnotobiotic mice

The aim of this study was to examine the role of indigenous lactobacilli in the physiological development of the stomach in mice using microarray analysis. In lactobacilli-associated gnotobiotic mice, an increased expression of the genes related to the muscle system development, such as nebulin and troponin, was observed. On the other hand, the expression of the gastrin gene dramatically decreased. A microarray analysis of the stomachs infected with H. pylori also showed both the up-regulation of muscle cell genes and the down-regulation of gastrin genes. Male germfree BALB/c mice were orally inoculated with 109 CFU lactobacilli and their stomachs were excised after 10 days for analyses. In the other experiment, 8-week-old mice were orally inoculated using a stomach tube on three consecutive days with 109 CFU of H. pylori. The stomachs of the germfree mice were used as controls. For the DNA microarray analysis, RNA was prepared from the stomach and then applied to a genome array.