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Mucus Secretion

  • Adrian Allen
  • Andrew C. Hunter
  • Anwar H. Mall

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.

Keywords

Mucus Secretion Duodenal Ulcer Patient Unstirred Layer Gastric Mucus Mucosal Protection 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Annotated Bibliography

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Copyright information

© Plenum Publishing Corporation 1989

Authors and Affiliations

  • Adrian Allen
    • 1
  • Andrew C. Hunter
    • 1
  • Anwar H. Mall
    • 1
  1. 1.Department of Physiological Sciences, Medical SchoolUniversity of Newcastle upon TyneNewcastle upon TyneEngland

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