INTRODUCTION: The rat undergoing restraint water-immersion stress(RWIS)is widely used to study the stress-induced gastric ulcer and to find the appropriate medical treatment which can cure this disease. Many evidence indicated that the gastric ulcer induced by the RWIS was mostly due to the hyperactivity of parasympathetic nerves that control the stomach. The vagal parasympathetic neurons innervating the stomach are largely located in the dorsal motor nucleus of the vagus (DMV) and partly in the nuc...