Stomach and duodenum

摘要

This section reviews the literature published within the past year pertaining to the stomach and duodenum. Specific topics include gastric secretion, gastroduodenal mu-cosal defense, dyspepsia and peptic ulcer, gastric motil-ity, and interventional endoscopy. It is hoped that these reviews will assist physicians, both in private practice and academics, in keeping up to date with rapid progress in the areas of gastroduodenal physiology and disease. The author thanks the reviewers for their excellent contributions.Gastric acid facilitates the digestion of protein and the absorption of iron, calcium and vitamin B12. It also protects against bacterial overgrowth and enteric infection. Gastric acid secretion is regulated by a number of overlapping neural (eg, vagus nerve, thyrotropin-releasing hormone, acetylcholine, gastrin-releasing peptide [bombesin], pituitary adenylate cyclase-activating pep-tide, and calcitonin gene-related peptide), hormonal (eg, gastrin), paracrine (eg, somatostatin, histamine, amylin, and atrial natriuretic peptide), and intracellular (eg, H+K+-ATPase and cyclooxygenase-2) pathways. It should be noted that the vagus nerve contains mostly afferent fibers that transmit sensory information from the gut to the brainstem. The signals are processed in the nucleus of the solitary tract then relayed to vagal efferent neurons.