Gastroduodenal mucosal defense: coordination by a network of messengers and mediators

Gastroduodenal mucosal defense is composed of structural features of the mu cosa, cellular monitors of pending or actual injury, and a web of effector cells that protect the mucosa from damage and govern its recovery from inju ry. By virtue of these systems, the gastroduodenal mucosa can cope with the harmful ingredients of ingested food and the potentially deleterious effec ts of gastric acid and pepsin. It is increasingly appreciated that a networ k of chemical messengers coordinates the alarm, defensive, and healing mech anisms. This article highlights some of the advances from the past year tha t have furthered our understanding of the regulatory systems that govern ga stroduodenal mucosal homeostasis. Particular emphasis is given to control o f the mucous and epithelial phospholipid barriers, the mucosal microcircula tion, and the epithelial, neural, immune, and inflammatory mediators of the mucosal repair mechanisms. Curr Opin Gastroenterol 2001, 17:489-496 (C) 20 01 Lippincott Williams & Wilkins, Inc.