Colon pp 45-63 | Cite as

The Structure of Colonic Mucus

  • Adrian Allen
Part of the Topics in Gastroenterology book series (TGEN)


Mucus is secreted as a viscoelastic gel that adheres to and covers the gastrointestinal mucosal surface. An accepted function of mucus throughout the gut is protection of the mucosal surface from mechanical damage by the passage of food or fecal material.1,2 In the stomach and the duodenum mucus forms a continuous gelatinous cover (average thickness about 50–200 µm) over the mucosa3 and is thought to provide the first line in mucosal defense against corrosive gastric secretions.4,5 In the colon the enteric microflora produce enzymes that can degrade both the carbohydrate and the protein components of mucous glycoprotein secretions6–9. In this way mucous secretions, including those from higher up the gut, can be digested and provide at the same time a nutrient source for the endogenous microflora. In other circumstances mucus may act as an antibacterial or antiviral agent.2,10 Various other functions have been suggested for gastrointestinal mucous secretions, including the binding of ions, for example, the selective binding of Na+ by colonic mucus.11 In general, however, the physiology of gastrointestinal mucus is poorly defined, owing in part to a lack of knowledge of the structure of these secretions.


Sialic Acid Mucous Secretion Carbohydrate Chain Gastric Mucus Mucous Glycoprotein 
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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Copyright information

© Plenum Publishing Corporation 1983

Authors and Affiliations

  • Adrian Allen
    • 1
  1. 1.Department of Physiological Sciences, The Medical SchoolThe University of Newcastle upon TyneNewcastle upon TyneEngland

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