Gastric mucus and gastroduodenal mucosal surface

The gastric mucus and gastroduodenal mucosal surface constitute a vital physiological defense system that shields the gastrointestinal epithelium from the caustic effects of gastric acid and the proteolytic enzyme pepsin (StatPearls: Physiology, Gastric Barrier [https://www.ncbi.nlm.nih.gov/books/NBK554439/]). This barrier is primarily composed of a hydrated gel layer of mucin glycoproteins, specifically MUC5AC and MUC6, which work in tandem with secreted bicarbonate to maintain a neutral pH at the cell surface (PubMed: Gastric Mucus [https://pubmed.ncbi.nlm.nih.gov/11588903/]). In addition to chemical protection, the mucus layer provides physical lubrication and acts as a sieve against pathogens like Helicobacter pylori. When this barrier is compromised by factors such as NSAIDs, alcohol, or infection, the resulting mucosal exposure leads to inflammation, erosions, and peptic ulcers. Therapeutic strategies targeting this surface include cytoprotective agents like sucralfate, which forms a protective paste over damaged tissue, and bismuth salts, which reinforce the barrier and provide antimicrobial activity (PubChem: Sucralfate [https://pubchem.ncbi.nlm.nih.gov/compound/Sucralfate]). These interventions are essential for restoring mucosal integrity and managing acid-related gastrointestinal disorders.

Other names

Gastric mucosal barrierGastroduodenal mucosal barrierGastric mucus layerGastric surface epithelium

Formation of a protective physical barrier; Stimulation of endogenous prostaglandin synthesis; Enhancement of mucus and bicarbonate secretion; Adsorption of pepsin and bile acids.