effect of pretreatment with ethanol or ammonium hydroxide on helicobacter pylori colonization in the stomach of rats

animal models for h.pylori infection have been developed to clarify the pathogenesis, testing new therapies and developing vaccines against human h.pylori infection. although rats have been used extensively for gastric ulceration and acid secretion studies, the animal is not normally infected with h.pylori.several chemicals such as ethanol and ammonium hydroxide can induce gastric erosion and interact with gastric mucosal defense mechanisms. the aim of the present study was to investigate the effects of pretreatment with the gastroinvasive agents on colonization of h. pylori with the gastroinvasive agents on colonization of h. pylori in not germ-free rats in order to overcome the resistance against h. pylori in rats. after 24 h fasting, the rats were divided into three major groups. animals in the first group were not pretreated with any chemicals. the two other groups were pretreated with ethanol (60%) or ammonium hydroxide (1%) before inoculation of 1 ml h. pylori suspension (3×108 cfu/ml). the results showed that h. pylori could not colonize in rats, even with ethanol or ammonium hydroxide pretreatment. an understanding of the mechanism of this resistance can help researchers to develop new therapeutic or preventive drugs against h. pylori and it is recommended to perform more investigation to clarify the reason of this resistance