Duodenal Protection: Influence of Melatonin and other Intestinal Transmitters on Duodenal Bicarbonate Secretion and Enterocyte Signaling

  • Gunnar Flemström
  • Markus Sjöblom


The duodenal epithelium secretes HC03 - at higher rates than does the stomach (or more distal small intestine) and the duodenal secretion is currently accepted as the most important defence mechanism against acid discharged from the stomach (4,6). HC03 - entering the continuous layer of visco-elastic mucus gel on top of the epithelial surface maintains pH in its cell-facing portion at neutrality at acidities encountered in the healthy duodenum.


Irritable Bowel Syndrome Cystic Fibrosis Transmembrane Conductance Regulator Pineal Gland Crypt Cell Carbonic Anhydrase Activity 
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© Springer Science+Business Media New York 2002

Authors and Affiliations

  • Gunnar Flemström
    • 1
  • Markus Sjöblom
    • 1
  1. 1.Department of PhysiologyUppsala UniversityUppsalaSweden

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