Effect of Pretreatment with Omeprazole on the Frequency of <I>Helicobacter pylori</I> Colonization in the Antrum and Gastric Body of Non-germ-free Immature Rats

Abstract

Differences between the colonization sites of Helicobacter pylori might explain the different patterns of H. pylori‐induced gastrointestinal pathology. The migration of H. pylori from the antrum to the gastric body and fundus during omeprazole monotherapy has been reported in H. pylori‐infected subjects. The aim of this study was to determine the influence of pretreatment with omeprazole on later colonization by H. pylori, by use of the rapid urease test, culture, and the polymerase chain reaction on gastric samples obtained from the antrum and gastric body of non‐germ‐free immature rats. Pretreatment of rats with omeprazole did not significantly affect the incidence of H. pylori colonization during the four‐week study. The preferred ecological niche of H. pylori in rats was the antrum rather than the gastric body. This difference was significant in animals not treated with omeprazole but not in treated groups, i.e. frequent injection of omeprazole led to the equal distribution of H. pylori in the antrum and gastric body. If clinical investigations confirm these results more precautions should be taken in omeprazole monotherapy because it is well known that H. pylori colonization of the gastric body is associated with multifocal gastric atrophy, an important risk factor in gastric adenocarcinoma.