胃粘膜表面覆盖一层粘液。粘液糖蛋白是构成粘液粘滞性及凝胶性的主要成分。前列腺素、胰泌素等促使粘液分泌增加,胆盐、酒精、非甾体类消炎药等抑制粘液生成,胃蛋白酶及幽门螺旋菌则使粘液糖蛋白分解。溃疡病时粘液层厚度及糖蛋白含量均减少。HCO_3~-分泌与胃腔内H~+浓度呈正相关,而与粘膜血流无关。粘液-HCO_3~-屏障能抵御H~+的逆弥散,并能使回渗的胃蛋白酶失活。 Mucosal surface covered with a layer of mucus. Mucoglycoprotein is a major component of mucus viscosity and gelation. Prostaglandins, secretin, etc. to promote increased mucus secretion, bile salts, alcohol, non-steroidal anti-inflammatory drugs inhibit mucus formation, pepsin and Helicobacter pylori is mucolytic glycoprotein decomposition. Mucous layer thickness and glycoprotein content were decreased in ulcer disease. HCO 3 ~ - secretion and gastric H ~ + concentration was positively correlated, but not with mucosal blood flow. Mucous-HCO 3 ~ - barrier can resist the inverse dispersion of H ~ +, and can inactivate the re-infiltration of pepsin.