Abstract
Mucus is the major organic secretion of the gut produced by epithelia throughout the gastrointestinal (GI) tract. It is apparent as a viscous secretion slopping over the mucosal surfaces. In histological sections, the presecreted mucus endows the gastroduodenal epithelia with its characteristic neutral [periodic acid-Schiff (PAS) stain] and acidic (Alcian blue or high iron diamine) staining characteristics. Such observations do not, however, indicate the true nature of the protective mucus barrier, which is a layer of water-insoluble gel firmly adherent to the epithelial surfaces and forming a continuous protective barrier between them and the gastric juice in the lumen. It should be emphasized that this adherent mucus layer exists as a stable gel phase that is physically quite distinct from the viscous sloppy soluble mucus mixed with the gastroduodenal luminal contents.
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Annotated Bibliography
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© 1989 Plenum Publishing Corporation
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Allen, A., Hunter, A.C., Mall, A.H. (1989). Mucus Secretion. In: Hollander, D., Tarnawski, A.S. (eds) Gastric Cytoprotection. Springer, Boston, MA. https://doi.org/10.1007/978-1-4684-5697-4_5
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DOI: https://doi.org/10.1007/978-1-4684-5697-4_5
Publisher Name: Springer, Boston, MA
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