The purpose of this paper is to discuss certain factors considered causal in thepathogenesis of peptic ulcer.
Basic Role of Peptic Digestion
The clinical evidence 1 of the basic role of peptic digestion may be summarized briefly: chronic peptic ulcer occurs only in those portions of the digestive tract exposed to the action of acid gastric juice, and it occurs only in persons whose stomachs secrete acid; its alleged occurrence with persistent achlorhydria is not well documented, although acute and chronic ulcer may occur in patients with low secretory patterns and with transitory achlorhydria. Peptic ulcers invariably heal if the achlorhydria lasts 3 months or longer.2,3The experimental evidence for this concept begins with the demonstration by Claude Bernard 4 that acid gastric juice is able to digest the leg of a living frog. Modern studies date from the demonstration by Williamson and Mann5 in 1923 that transplantation of