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. 1981 May;314:429–443. doi: 10.1113/jphysiol.1981.sp013717

Intestinal bicarbonate secretion in Amphiuma measured by pH stat in vitro: relationship with metabolism and transport of sodium and chloride ions.

M A Imon, J F White
PMCID: PMC1249443  PMID: 7310697

Abstract

1. Isolated Amphiuma small intestine exposed on both surfaces to buffered or unbuffered media generated gradients of pH under short-circuited conditions consistent with secretion of HCO3(-). 2. When unbuffered mucosal medium was maintained at pH 7.4 by addition of acid, alkalinization of the mucosal medium occurred at a rate of 1-2 microequiv/hr cm2 under short-circuit conditions (Isc) and was reduced by anoxia, acetazolamide or removal of CO2. 3. The rate of HCO3(-) secretion (JHCO3(-)) was reduced at a mucosal pH above or below 7.4 and was proportional to serosal HCO3(-). 4. JHCO3(-) was reduced in Na+-free (choline) and Cl-free (SO4(2-) media and after exposure to the stilbene SITS. 5. The difference JHCO3(-)--Isc was consistent with net Cl- absorption. 6. The tissue resistance (Rt) was elevated upon exposure to serosal HCO3(-) and lowered by mucosal HCO3(-). 7. The intestinal mucosa exhibited carbonic anhydrase activity that was sensitive to ethoxazolamide. 8. It is concluded that HCO3(-) secretion is active, influenced by intracellular carbonic anhydrase activity and coupled to Cl- and possibly Na+ absorption.

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. Brodsky W. A., Durham J., Ehrenspeck G. The effects of a disulphonic stilbene on chloride and bicarbonate transport in the turtle bladder. J Physiol. 1979 Feb;287:559–573. doi: 10.1113/jphysiol.1979.sp012677. [DOI] [PMC free article] [PubMed] [Google Scholar]
  2. Cabantchik Z. I., Rothstein A. The nature of the membrane sites controlling anion permeability of human red blood cells as determined by studies with disulfonic stilbene derivatives. J Membr Biol. 1972 Dec 29;10(3):311–330. doi: 10.1007/BF01867863. [DOI] [PubMed] [Google Scholar]
  3. Carter M. J., Parsons D. S. The isoenzymes of carbonic anhydrase: tissue, subcellular distribution and functional significance, with particular reference to the intestinal tract. J Physiol. 1971 May;215(1):71–94. doi: 10.1113/jphysiol.1971.sp009458. [DOI] [PMC free article] [PubMed] [Google Scholar]
  4. Dietz J., Field M. Ion transport in rabbit ileal mucosa. IV. Bicarbonate secretion. Am J Physiol. 1973 Oct;225(4):858–861. doi: 10.1152/ajplegacy.1973.225.4.858. [DOI] [PubMed] [Google Scholar]
  5. Frizzell R. A., Markscheid-Kaspi L., Schultz S. G. Oxidative metabolism of rabbit ileal mucosa. Am J Physiol. 1974 May;226(5):1142–1148. doi: 10.1152/ajplegacy.1974.226.5.1142. [DOI] [PubMed] [Google Scholar]
  6. Hubel K. A. Bicarbonate secretion in rat ileum and its dependence on intraluminal chloride. Am J Physiol. 1967 Dec;213(6):1409–1413. doi: 10.1152/ajplegacy.1967.213.6.1409. [DOI] [PubMed] [Google Scholar]
  7. Hubel K. A. Effect of luminal chloride concentration on bicarbonate secretion in rat ileum. Am J Physiol. 1969 Jul;217(1):40–45. doi: 10.1152/ajplegacy.1969.217.1.40. [DOI] [PubMed] [Google Scholar]
  8. Humphreys M. H., Chou L. Y. Anion-stimulated ATPase activity of brush border from rat small intestine. Am J Physiol. 1979 Jan;236(1):E70–E76. doi: 10.1152/ajpendo.1979.236.1.E70. [DOI] [PubMed] [Google Scholar]
  9. Jackson M. J., Morgan B. N. Relations of weak-electrolyte transport and acid-base metabolism in rat small intestine in vitro. Am J Physiol. 1975 Feb;228(2):482–487. doi: 10.1152/ajplegacy.1975.228.2.482. [DOI] [PubMed] [Google Scholar]
  10. KINNEY V. R., CODE C. F. CANINE ILEAL CHLORIDE ABSORPTION: EFFECT OF CARBONIC ANHYDRASE INHIBITOR ON TRANSPORT. Am J Physiol. 1964 Nov;207:998–1004. doi: 10.1152/ajplegacy.1964.207.5.998. [DOI] [PubMed] [Google Scholar]
  11. KURIAKI K., MAGEE D. F. ON THE CARBONIC ANHYDRASE ACTIVITY OF THE ALIMINTARY CANAL AND PANCREAS. Life Sci. 1964 Dec;3:1377–1382. doi: 10.1016/0024-3205(64)90077-3. [DOI] [PubMed] [Google Scholar]
  12. Lew V. L. Short-circuit current and ionic fluxes in the isolated colonic mucosa of Bufo arenarum. J Physiol. 1970 Mar;206(3):509–528. doi: 10.1113/jphysiol.1970.sp009028. [DOI] [PMC free article] [PubMed] [Google Scholar]
  13. Maren T. H. Carbonic anhydrase: chemistry, physiology, and inhibition. Physiol Rev. 1967 Oct;47(4):595–781. doi: 10.1152/physrev.1967.47.4.595. [DOI] [PubMed] [Google Scholar]
  14. Maren T. H. Use of inhibitors in physiological studies of carbonic anhydrase. Am J Physiol. 1977 Apr;232(4):F291–F297. doi: 10.1152/ajprenal.1977.232.4.F291. [DOI] [PubMed] [Google Scholar]
  15. Nellans H. N., Frizzell R. A., Schultz S. G. Effect of acetazolamide on sodium and chloride transport by in vitro rabbit ileum. Am J Physiol. 1975 Jun;228(6):1808–1814. doi: 10.1152/ajplegacy.1975.228.6.1808. [DOI] [PubMed] [Google Scholar]
  16. Powell D. W., Binder H. J., Curran P. F. Electrolyte secretion by the guinea pig ileum in vitro. Am J Physiol. 1972 Sep;223(3):531–537. doi: 10.1152/ajplegacy.1972.223.3.531. [DOI] [PubMed] [Google Scholar]
  17. Sanders S. S., Hayne V. B., Jr, Rehm W. S. Normal H+ rates in frog stomach in absence of exogenous CO2 and a note on pH stat method. Am J Physiol. 1973 Dec;225(6):1311–1321. doi: 10.1152/ajplegacy.1973.225.6.1311. [DOI] [PubMed] [Google Scholar]
  18. Scheid P. Respiration and control of breathing in birds. Physiologist. 1979 Oct;22(5):60–64. [PubMed] [Google Scholar]
  19. Sheerin H. E., Field M. Ileal HCO3 secretion: relationship to Na and Cl transport and effect of theophylline. Am J Physiol. 1975 Apr;228(4):1065–1074. doi: 10.1152/ajplegacy.1975.228.4.1065. [DOI] [PubMed] [Google Scholar]
  20. Sorenson M. M., Reuben J. P., Eastwood A. B., Orentlicher M., Katz G. M. Functional heterogeneity of the sarcoplasmic reticulum within sarcomeres of skinned muscle fibers. J Membr Biol. 1980 Mar 31;53(1):1–17. doi: 10.1007/BF01871168. [DOI] [PubMed] [Google Scholar]
  21. Swallow J. H., Code C. F. Intestinal transmucosal fluxes of bicarbonate. Am J Physiol. 1967 Mar;212(3):717–723. doi: 10.1152/ajplegacy.1967.212.3.717. [DOI] [PubMed] [Google Scholar]
  22. Turnberg L. A., Bieberdorf F. A., Morawski S. G., Fordtran J. S. Interrelationships of chloride, bicarbonate, sodium, and hydrogen transport in the human ileum. J Clin Invest. 1970 Mar;49(3):557–567. doi: 10.1172/JCI106266. [DOI] [PMC free article] [PubMed] [Google Scholar]
  23. WILSON T. H. Concentration gradients of lactate, hydrogen and some other ions across the intestine in vitro. Biochem J. 1954 Mar;56(3):521–527. doi: 10.1042/bj0560521. [DOI] [PMC free article] [PubMed] [Google Scholar]
  24. White J. F. Alterations in electrophysiology of isolated amphibian small intestine produced by removing the muscle layers. Biochim Biophys Acta. 1977 May 16;467(1):91–102. doi: 10.1016/0005-2736(77)90245-0. [DOI] [PubMed] [Google Scholar]

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