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

  • Gunnar Flemström
  • Markus Sjöblom

Abstract

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.

Keywords

Serotonin Prostaglandin Luminal Tryptophan Gentamicin 

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. 1.
    Chew CS, Ljungström M, Smolka A, and Brown MR. Primary culture of secretagogue-responsive parietal cells. Am J Physiol Gastrointest Liver Physiol 256: G254–G263, 1989.Google Scholar
  2. 2.
    Chew CS, Säfsten B, and Flemström G. Calcium signaling in cultured human and rat duodenal enterocytes. Am J Physiol Gastrointest Liver Physiol 275: G296–G304, 1998.Google Scholar
  3. 3.
    Clarke LL, and Harline MC. Dual role of CFTR in cAMP-stimulated HCO3 - secretion across murine duodenum. Am J Physiol Gastrointest Liver Physiol 214: G718–G726, 1998.Google Scholar
  4. 4.
    Flemström G. Gastric and duodenal mucosal bicarbonate secretion. In: Physiology of the Gastrointestinal Tract (3rd ed.), edited by Johnson LR, Jacobson ED, Christensen J, Alpers D, and Walsh JH, New York: Raven, 1994, p. 1285–1309.Google Scholar
  5. 5.
    Flemström G, and Jedstedt G. Stimulation of duodenal mucosal bicarbonate secretion in the rat by brain peptides. Gastroenterology 97: 412–420, 1989.PubMedGoogle Scholar
  6. 6.
    Flemström G, and Isenberg, JI. Gastroduodenal mucosal alkaline secretion and mucosal protection. News Physiol Sci 16: 23–28, 2001.PubMedGoogle Scholar
  7. 7.
    Hogan DL, Crombie DL, Isenberg JI, Svendsen P, Schaffalitsky de Muchadell OB, and Ainsworth MA. CFTR regulates cAMP- and Ca2+-mediated duodenal epithelial secretion. Am J Physiol Gastrointest Liver Physiol 272: G872–G876, 1997.Google Scholar
  8. 8.
    Huether G, Poeggeler, B, Reimer A., and George A. Effect of tryptophan administration on circulating melatonin levels in chicks and rats: evidence for stimulation of melatonin synthesis and release in the gastrointestinal tract. Life Sci 51: 945–953, 1992.PubMedCrossRefGoogle Scholar
  9. 9.
    Isenberg JI, Ljungström M, Säfsten B, and Flemström G. Proximal duodenal enterocyte transport: evidence for Na+-H+ and Cl--HC03 - exchange and NaHCO3 cotransport. Am J Physiol Gastrointest Liver Physiol 265: G677–G685, 1993.Google Scholar
  10. 10.
    Joo NS, London RM, Kim HD, Forte LR, and Clarke LL. Regulation of intestinal Cl- and HCO3 - secretion by uroguanylin. Am J Physiol Gastrointest Liver Physiol 274: G633–G644, 1998.Google Scholar
  11. 11.
    Larsen KR, Moore JG, and Dayton MT. Circadian rhythms of acid and bicarbonate efflux in fasting rat stomach. Am J Physiol Gastrointest Liver Physiol 260: G610–G614, 1991.Google Scholar
  12. 12.
    Larson GM, Jedstedt G, Nylander O, and Flemström G. Intracerebral adrenoceptor agonists influence rat duodenal mucosal bicarbonate secretion. Am J Physiol Gastrointest Liver Physiol 271: G831–G840, 1996.Google Scholar
  13. 13.
    Lee PP, and Pang SF. Melatonin and its receptors in the gastrointestinal tract. Biol Signals 2:181–193, 1993.PubMedCrossRefGoogle Scholar
  14. 14.
    Lönnerholm GL, Knutson L, Wistrand PJ, and Flemström G. Carbonic anhydrase in the normal rat stomach and duodenum and after treatment with omeprazole and ranitidine. Acta Physiol Scand 136: 253–262, 1989.PubMedCrossRefGoogle Scholar
  15. 15.
    Pratha VS, Hogan DL, Mårtensson BA, Bernard J, Zhou R, and Isenberg JI. Identification of transport abnormalities in duodenal mucosa and duodenal enterocytes from patients with cystic fibrosis. Gastroenterology 118: 1051–1060, 2000.PubMedCrossRefGoogle Scholar
  16. 16.
    Raikhlin NT, and Kvetnoy IM. Melatonin and enterochromaffme cells. Acta Histochem 55:19–24, 1976PubMedCrossRefGoogle Scholar
  17. 17.
    Shariatmadari R, Lund PE, Krijukova E, Sperber GO, Kukkonen JP, and Åkerman KEO. Reconstitution of neurotransmission by determining communication between differentiated PC12 pheochromocytoma and HEL 92.1.7 eythroleukemia cells. Pflügers Arch-Eur JPhysiol 442: 312–320, 2001CrossRefGoogle Scholar
  18. 18.
    Sjöblom M, Jedstedt G, and Flemström G. Peripheral melatonin mediates neural stimulation of duodenal mucosal bicarbonate secretion. J Clin Invest 108: 625–633, 2001PubMedGoogle Scholar
  19. 19.
    Sjöblom M, Jedstedt G, and Flemström G. Effects of melatonin on duodenal enterocyte calcium signaling and bicarbonate secretion (abstr). Gastroenterology 120: A-312,2001.Google Scholar
  20. 20.
    Seidler U, Blumenstein I, Kretz A, Viellard-Baron D, Rossmann H, Colledge WH, Evans M, Rateliff R, and Gregor M. A functional CFTR protein is required for mouse intestinal cAMP-, cGMP- and Ca(2+)-dependent HC03 - secretion. J Physiol (Lond) 505: 411–423, 1997.CrossRefGoogle Scholar
  21. 21.
    Trier JS. Studies of the small intestinal crypt epithelium. II. Evidence for and mechanisms of secretory activity by undifferentiated crypt cells of the human small intestine. Gastroenterology 47: 480–495, 1964.PubMedGoogle Scholar
  22. 22.
    Vanecek J. Cellular mechanisms of melatonin action. Physiol Rev 78: 687–721, 1998.PubMedGoogle Scholar

Copyright information

© Springer Science+Business Media New York 2002

Authors and Affiliations

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

Personalised recommendations