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. 1987 Apr 1;89(4):581–598. doi: 10.1085/jgp.89.4.581

Basolateral membrane Cl/HCO3 exchange in the rat proximal convoluted tubule. Na-dependent and -independent modes

PMCID: PMC2215917  PMID: 2953859

Abstract

To examine whether Cl-coupled HCO3 transport mechanisms were present on the basolateral membrane of the mammalian proximal tubule, cell pH was measured in the microperfused rat proximal convoluted tubule using the pH-sensitive, intracellularly trapped fluorescent dye (2',7')- bis(carboxyethyl)-(5,6)-carboxyfluorescein. Increasing the peritubular Cl concentration from 0 to 128.6 meq/liter caused cell pH to decrease from 7.34 +/- 0.04 to 7.21 +/- 0.04 (p less than 0.001). With more acid extracellular fluid (pH 6.62), a similar increase in the peritubular Cl concentration caused cell pH to decrease by a similar amount from 6.97 +/- 0.04 to 6.84 +/- 0.05 (p less than 0.001). This effect was blocked by 1 mM SITS. To examine the Na dependence of Cl/HCO3 exchange, the above studies were repeated in the absence of luminal and peritubular Na. In alkaline Na-free solutions, peritubular Cl addition caused cell pH to decrease from 7.57 +/- 0.06 to 7.53 +/- 0.06 (p less than 0.025); in acid Na-free solutions, peritubular Cl addition caused cell pH to decrease from 7.21 +/- 0.04 to 7.19 +/- 0.04 (p less than 0.05). The effect of Cl on cell pH was smaller in the absence of luminal and peritubular Na than in its presence. To examine whether the previously described Na/(HCO3)n greater than 1 cotransporter was coupled to or dependent on Cl, the effect of lowering the peritubular Na concentration from 147 to 25 meq/liter was examined in the absence of ambient Cl. Cell pH decreased from 7.28 +/- 0.03 to 7.08 +/- 0.03, a response similar to that observed previously in the presence of Cl. The results demonstrate that Cl/HCO3 (or Cl/OH) exchange is present on the basolateral membrane. Most of Cl/HCO3 exchange is dependent on the presence of Na and may be coupled to it. The previously described Na/(HCO3)n greater than 1 cotransporter is the major basolateral membrane pathway for the coupling of Na and HCO3 and is not coupled to Cl.

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Selected References

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  1. Akiba T., Alpern R. J., Eveloff J., Calamina J., Warnock D. G. Electrogenic sodium/bicarbonate cotransport in rabbit renal cortical basolateral membrane vesicles. J Clin Invest. 1986 Dec;78(6):1472–1478. doi: 10.1172/JCI112738. [DOI] [PMC free article] [PubMed] [Google Scholar]
  2. Alpern R. J. Bicarbonate-water interactions in the rat proximal convoluted tubule. An effect of volume flux on active proton secretion. J Gen Physiol. 1984 Nov;84(5):753–770. doi: 10.1085/jgp.84.5.753. [DOI] [PMC free article] [PubMed] [Google Scholar]
  3. Alpern R. J., Chambers M. Cell pH in the rat proximal convoluted tubule. Regulation by luminal and peritubular pH and sodium concentration. J Clin Invest. 1986 Aug;78(2):502–510. doi: 10.1172/JCI112602. [DOI] [PMC free article] [PubMed] [Google Scholar]
  4. Alpern R. J., Howlin K. J., Preisig P. A. Active and passive components of chloride transport in the rat proximal convoluted tubule. J Clin Invest. 1985 Oct;76(4):1360–1366. doi: 10.1172/JCI112111. [DOI] [PMC free article] [PubMed] [Google Scholar]
  5. Alpern R. J. Mechanism of basolateral membrane H+/OH-/HCO-3 transport in the rat proximal convoluted tubule. A sodium-coupled electrogenic process. J Gen Physiol. 1985 Nov;86(5):613–636. doi: 10.1085/jgp.86.5.613. [DOI] [PMC free article] [PubMed] [Google Scholar]
  6. Baum M., Berry C. A. Evidence for neutral transcellular NaCl transport and neutral basolateral chloride exit in the rabbit proximal convoluted tubule. J Clin Invest. 1984 Jul;74(1):205–211. doi: 10.1172/JCI111403. [DOI] [PMC free article] [PubMed] [Google Scholar]
  7. Becker B. F., Duhm J. Evidence for anionic cation transport of lithium, sodium and potassium across the human erythrocyte membrane induced by divalent anions. J Physiol. 1978 Sep;282:149–168. doi: 10.1113/jphysiol.1978.sp012454. [DOI] [PMC free article] [PubMed] [Google Scholar]
  8. Biagi B. A. Effects of the anion transport inhibitor, SITS, on the proximal straight tubule of the rabbit perfused in vitro. J Membr Biol. 1985;88(1):25–31. doi: 10.1007/BF01871210. [DOI] [PubMed] [Google Scholar]
  9. Boron W. F., Boulpaep E. L. Intracellular pH regulation in the renal proximal tubule of the salamander. Basolateral HCO3- transport. J Gen Physiol. 1983 Jan;81(1):53–94. doi: 10.1085/jgp.81.1.53. [DOI] [PMC free article] [PubMed] [Google Scholar]
  10. Burckhardt B. C., Cassola A. C., Frömter E. Electrophysiological analysis of bicarbonate permeation across the peritubular cell membrane of rat kidney proximal tubule. II. Exclusion of HCO3(-)-effects on other ion permeabilities and of coupled electroneutral HCO3(-)-transport. Pflugers Arch. 1984 May;401(1):43–51. doi: 10.1007/BF00581531. [DOI] [PubMed] [Google Scholar]
  11. Cassola A. C., Mollenhauer M., Frömter E. The intracellular chloride activity of rat kidney proximal tubular cells. Pflugers Arch. 1983 Dec;399(4):259–265. doi: 10.1007/BF00652749. [DOI] [PubMed] [Google Scholar]
  12. Edelman A., Bouthier M., Anagnostopoulos T. Chloride distribution in the proximal convoluted tubule of Necturus kidney. J Membr Biol. 1981;62(1-2):7–17. doi: 10.1007/BF01870195. [DOI] [PubMed] [Google Scholar]
  13. Fischer J. L., Husted R. F., Steinmetz P. R. Chloride dependence of the HCO3 exit step in urinary acidification by the turtle bladder. Am J Physiol. 1983 Nov;245(5 Pt 1):F564–F568. doi: 10.1152/ajprenal.1983.245.5.F564. [DOI] [PubMed] [Google Scholar]
  14. Frömter E. Electrophysiological analysis of rat renal sugar and amino acid transport. I. Basic phenomena. Pflugers Arch. 1982 Apr;393(2):179–189. doi: 10.1007/BF00582942. [DOI] [PubMed] [Google Scholar]
  15. Frömter E., Gessner K. Active transport potentials, membrane diffusion potentials and streaming potentials across rat kidney proximal tubule. Pflugers Arch. 1974;351(1):85–98. doi: 10.1007/BF00603513. [DOI] [PubMed] [Google Scholar]
  16. Funder J., Tosteson D. C., Wieth J. O. Effects of bicarbonate on lithium transport in human red cells. J Gen Physiol. 1978 Jun;71(6):721–746. doi: 10.1085/jgp.71.6.721. [DOI] [PMC free article] [PubMed] [Google Scholar]
  17. Grassl S. M., Aronson P. S. Na+/HCO3-co-transport in basolateral membrane vesicles isolated from rabbit renal cortex. J Biol Chem. 1986 Jul 5;261(19):8778–8783. [PubMed] [Google Scholar]
  18. Green R., Bishop J. H., Giebisch G. Ionic requirements of proximal tubular sodium transport. III. Selective luminal anion substitution. Am J Physiol. 1979 Mar;236(3):F268–F277. doi: 10.1152/ajprenal.1979.236.3.F268. [DOI] [PubMed] [Google Scholar]
  19. Guggino W. B., Boulpaep E. L., Giebisch G. Electrical properties of chloride transport across the necturus proximal tubule. J Membr Biol. 1982;65(3):185–196. doi: 10.1007/BF01869962. [DOI] [PubMed] [Google Scholar]
  20. Guggino W. B., London R., Boulpaep E. L., Giebisch G. Chloride transport across the basolateral cell membrane of the Necturus proximal tubule: dependence on bicarbonate and sodium. J Membr Biol. 1983;71(3):227–240. doi: 10.1007/BF01875464. [DOI] [PubMed] [Google Scholar]
  21. Howlin K. J., Alpern R. J., Berry C. A., Rector F. C., Jr Evidence for electroneutral sodium chloride transport in rat proximal convoluted tubule. Am J Physiol. 1986 Apr;250(4 Pt 2):F644–F648. doi: 10.1152/ajprenal.1986.250.4.F644. [DOI] [PubMed] [Google Scholar]
  22. Löw I., Friedrich T., Burckhardt G. Properties of an anion exchanger in rat renal basolateral membrane vesicles. Am J Physiol. 1984 Mar;246(3 Pt 2):F334–F342. doi: 10.1152/ajprenal.1984.246.3.F334. [DOI] [PubMed] [Google Scholar]
  23. Moolenaar W. H., Tsien R. Y., van der Saag P. T., de Laat S. W. Na+/H+ exchange and cytoplasmic pH in the action of growth factors in human fibroblasts. Nature. 1983 Aug 18;304(5927):645–648. doi: 10.1038/304645a0. [DOI] [PubMed] [Google Scholar]
  24. Rink T. J., Tsien R. Y., Pozzan T. Cytoplasmic pH and free Mg2+ in lymphocytes. J Cell Biol. 1982 Oct;95(1):189–196. doi: 10.1083/jcb.95.1.189. [DOI] [PMC free article] [PubMed] [Google Scholar]
  25. Roos A., Boron W. F. Intracellular pH. Physiol Rev. 1981 Apr;61(2):296–434. doi: 10.1152/physrev.1981.61.2.296. [DOI] [PubMed] [Google Scholar]
  26. Schwartz G. J., Barasch J., Al-Awqati Q. Plasticity of functional epithelial polarity. 1985 Nov 28-Dec 4Nature. 318(6044):368–371. doi: 10.1038/318368a0. [DOI] [PubMed] [Google Scholar]
  27. Shindo T., Spring K. R. Chloride movement across the basolateral membrane of proximal tubule cells. J Membr Biol. 1981 Jan 30;58(1):35–42. doi: 10.1007/BF01871032. [DOI] [PubMed] [Google Scholar]
  28. Stone D. K., Seldin D. W., Kokko J. P., Jacobson H. R. Anion dependence of rabbit medullary collecting duct acidification. J Clin Invest. 1983 May;71(5):1505–1508. doi: 10.1172/JCI110905. [DOI] [PMC free article] [PubMed] [Google Scholar]
  29. Thomas J. A., Buchsbaum R. N., Zimniak A., Racker E. Intracellular pH measurements in Ehrlich ascites tumor cells utilizing spectroscopic probes generated in situ. Biochemistry. 1979 May 29;18(11):2210–2218. doi: 10.1021/bi00578a012. [DOI] [PubMed] [Google Scholar]
  30. Thomas R. C. The role of bicarbonate, chloride and sodium ions in the regulation of intracellular pH in snail neurones. J Physiol. 1977 Dec;273(1):317–338. doi: 10.1113/jphysiol.1977.sp012096. [DOI] [PMC free article] [PubMed] [Google Scholar]
  31. Yoshitomi K., Burckhardt B. C., Frömter E. Rheogenic sodium-bicarbonate cotransport in the peritubular cell membrane of rat renal proximal tubule. Pflugers Arch. 1985 Dec;405(4):360–366. doi: 10.1007/BF00595689. [DOI] [PubMed] [Google Scholar]
  32. Yoshitomi K., Frömter E. How big is the electrochemical potential difference of Na+ across rat renal proximal tubular cell membranes in vivo? Pflugers Arch. 1985;405 (Suppl 1):S121–S126. doi: 10.1007/BF00581792. [DOI] [PubMed] [Google Scholar]

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