Recent studies from this laboratory, as well as elsewhere, have demonstrated that the antrum of the stomach is an important endocrine organ, distinct in function from other parts of the gastrointestinal tract. An understanding of the endocrine function of the antrum and of its external secretion should be helpful in the surgical treatment of peptic ulcer and provide a more complete understanding of the physiology of gastric secretion. In the total gastric pouch, the antrum is isolated from contact with food or distending stimuli and is continually bathed in the undiluted acid gastric secretion of the fundus. In a previous study from this laboratory it was concluded that in this situation the antrum is quiescent.1Removal of the antrum from the isolated stomach and its transplantation to the duodenum or to the transverse colon as a diverticulum caused a tremendous augmentation in gastric secretion. This stimulation in gastric secretion