ABSTRACT
I. BACKGROUND A. Duodenal Ulcer Duodenal ulceration is fundamentally a disease of excess acid load in the duodenum, although alterations in protective factors also playa role. Gastric acid secretion is under the regulatory control of three important influences: parasympathetic stimulation via the vagus nerve, histaminergic receptor agonism, and gastrin produced by the antrum. The role of the vagus nerve in regulating gastric acid secretion, as delineated by Prout, Beaumont, Pavlov, Dragsted and others, coupled with the anatomical descriptions of the vagus nerve, beginning with those attributed to Galen, led to the development of a number of highly effective operations designed to minimize acid production in keeping with Schwarz's dictum of "no acid, no ulcer." Consequently, peptic ulcer disease (PUD) of the duodenum was one of the most common indications for elective gastric surgery as recently as the 1960s and early 1970s.
