, Volume 10, Issue 4–6, pp 327–332 | Cite as

Duodenal defence mechanisms: role of mucosal bicarbonate secretion

  • Gunnar Flemström
  • Markus Sjöblom


The duodenal epithelium secretes bicarbonate 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. HCO3- 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. The secretion is decreased in patients with acute and chronic duodenal ulcer disease and is inhibited by non-steroidal anti-inflammatory agents. Studies of the neurohumoral control of the duodenal alkaline secretion and of acid/base transport processes and intracellular signaling in duodenal enterocytes are currently of great research interest.



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© VSP 2002 2002

Authors and Affiliations

  • Gunnar Flemström
  • Markus Sjöblom

There are no affiliations available

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