Abstract
Proton and formic acid permeabilities were measured in the in vivo microperfused rat proximal convoluted tubule by examining the effect on intracellular pH when [H] and/or [formic acid] were rapidly changed in the luminal or peritubular fluids. Apical and basolateral membrane H permeabilities were 0.52 +/- 0.07 and 0.67 +/- 0.18 cm/s, respectively. Using these permeabilities we calculate that proton backleak from the luminal fluid to cell does not contribute significantly to net proton secretion in the early proximal tubule, but may contribute in the late proximal tubule. Apical and basolateral membrane formic acid permeabilities measured at extracellular pH 6.62 were 4.6 +/- 0.5 X 10(-2) and 6.8 +/- 1.5 X 10(-2) cm/s, respectively. Control studies demonstrated that the formic acid permeabilities were not underestimated by either the simultaneous movement of formate into the cell or the efflux of formic acid across the opposite membrane. The measured apical membrane formic acid permeability is too small to support all of transcellular NaCl absorption in the rat by a mechanism that involves Na/H-Cl/formate transporters operating in parallel with formic acid nonionic diffusion.
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Selected References
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- Alpern R. J. Apical membrane chloride/base exchange in the rat proximal convoluted tubule. J Clin Invest. 1987 Apr;79(4):1026–1030. doi: 10.1172/JCI112914. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 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]
- 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]
- Alpern R. J., Cogan M. G., Rector F. C., Jr Effect of luminal bicarbonate concentration on proximal acidification in the rat. Am J Physiol. 1982 Jul;243(1):F53–F59. doi: 10.1152/ajprenal.1982.243.1.F53. [DOI] [PubMed] [Google Scholar]
- 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]
- 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]
- 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]
- Baum M. Effect of luminal chloride on cell pH in rabbit proximal tubule. Am J Physiol. 1988 May;254(5 Pt 2):F677–F683. doi: 10.1152/ajprenal.1988.254.5.F677. [DOI] [PubMed] [Google Scholar]
- Baum M. Evidence that parallel Na+-H+ and Cl(-)-HCO3-(OH-) antiporters transport NaCl in the proximal tubule. Am J Physiol. 1987 Feb;252(2 Pt 2):F338–F345. doi: 10.1152/ajprenal.1987.252.2.F338. [DOI] [PubMed] [Google Scholar]
- Bidet M., Tauc M., Merot J., Vandewalle A., Poujeol P. Na+-H+ exchanger in proximal cells isolated from rabbit kidney. I. Functional characteristics. Am J Physiol. 1987 Nov;253(5 Pt 2):F935–F944. doi: 10.1152/ajprenal.1987.253.5.F935. [DOI] [PubMed] [Google Scholar]
- Boron W. F. Intracellular pH transients in giant barnacle muscle fibers. Am J Physiol. 1977 Sep;233(3):C61–C73. doi: 10.1152/ajpcell.1977.233.3.C61. [DOI] [PubMed] [Google Scholar]
- Chan Y. L., Biagi B., Giebisch G. Control mechanisms of bicarbonate transport across the rat proximal convoluted tubule. Am J Physiol. 1982 May;242(5):F532–F543. doi: 10.1152/ajprenal.1982.242.5.F532. [DOI] [PubMed] [Google Scholar]
- Chantrelle B. M., Cogan M. G., Rector F. C., Jr Active and passive components of NaCl absorption in the proximal convoluted tubule of the rat kidney. Miner Electrolyte Metab. 1985;11(4):209–214. [PubMed] [Google Scholar]
- Cogan M. G., Maddox D. A., Warnock D. G., Lin E. T., Rector F. C., Jr Effect of acetazolamide on bicarbonate reabsorption in the proximal tubule of the rat. Am J Physiol. 1979 Dec;237(6):F447–F454. doi: 10.1152/ajprenal.1979.237.6.F447. [DOI] [PubMed] [Google Scholar]
- Cogan M. G., Rector F. C., Jr Determinants of proximal bicarbonate, chloride, and water reabsorption during carbonic anhydrase inhibition. Am J Physiol. 1982 Mar;242(3):F274–F284. doi: 10.1152/ajprenal.1982.242.3.F274. [DOI] [PubMed] [Google Scholar]
- Diamond J. M., Wright E. M. Biological membranes: the physical basis of ion and nonelectrolyte selectivity. Annu Rev Physiol. 1969;31:581–646. doi: 10.1146/annurev.ph.31.030169.003053. [DOI] [PubMed] [Google Scholar]
- DuBose T. D., Jr, Pucacco L. R., Lucci M. S., Carter N. W. Micropuncture determination of pH, PCO2, and total CO2 concentration in accessible structures of the rat renal cortex. J Clin Invest. 1979 Aug;64(2):476–482. doi: 10.1172/JCI109485. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Finkelstein A. Water and nonelectrolyte permeability of lipid bilayer membranes. J Gen Physiol. 1976 Aug;68(2):127–135. doi: 10.1085/jgp.68.2.127. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 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]
- Gutknecht J. Proton/hydroxide conductance and permeability through phospholipid bilayer membranes. Proc Natl Acad Sci U S A. 1987 Sep;84(18):6443–6446. doi: 10.1073/pnas.84.18.6443. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Hamm L. L., Pucacco L. R., Kokko J. P., Jacobson H. R. Hydrogen ion permeability of the rabbit proximal convoluted tubule. Am J Physiol. 1984 Jan;246(1 Pt 2):F3–11. doi: 10.1152/ajprenal.1984.246.1.F3. [DOI] [PubMed] [Google Scholar]
- 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]
- Ives H. E. Proton/hydroxyl permeability of proximal tubule brush border vesicles. Am J Physiol. 1985 Jan;248(1 Pt 2):F78–F86. doi: 10.1152/ajprenal.1985.248.1.F78. [DOI] [PubMed] [Google Scholar]
- Jacobson H. R. Effects of CO2 and acetazolamide on bicarbonate and fluid transport in rabbit proximal tubules. Am J Physiol. 1981 Jan;240(1):F54–F62. doi: 10.1152/ajprenal.1981.240.1.F54. [DOI] [PubMed] [Google Scholar]
- Karniski L. P., Aronson P. S. Chloride/formate exchange with formic acid recycling: a mechanism of active chloride transport across epithelial membranes. Proc Natl Acad Sci U S A. 1985 Sep;82(18):6362–6365. doi: 10.1073/pnas.82.18.6362. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Klocke R. A., Andersson K. K., Rotman H. H., Forster R. E. Permeability of human erythrocytes to ammonia and weak acids. Am J Physiol. 1972 Apr;222(4):1004–1013. doi: 10.1152/ajplegacy.1972.222.4.1004. [DOI] [PubMed] [Google Scholar]
- Lucci M. S., Pucacco L. R., DuBose T. D., Jr, Kokko J. P., Carter N. W. Direct evaluation of acidification by rat proximal tubule: role of carbonic anhydrase. Am J Physiol. 1980 May;238(5):F372–F379. doi: 10.1152/ajprenal.1980.238.5.F372. [DOI] [PubMed] [Google Scholar]
- Lucci M. S., Warnock D. G. Effects of anion-transport inhibitors on NaCl reabsorption in the rat superficial proximal convoluted tubule. J Clin Invest. 1979 Aug;64(2):570–579. doi: 10.1172/JCI109495. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Molitoris B. A., Simon F. R. Renal cortical brush-border and basolateral membranes: cholesterol and phospholipid composition and relative turnover. J Membr Biol. 1985;83(3):207–215. doi: 10.1007/BF01868695. [DOI] [PubMed] [Google Scholar]
- Nord E. P., Wright S. H., Kippen I., Wright E. M. Specificity of the Na+-dependent monocarboxylic acid transport pathway in rabbit renal brush border membranes. J Membr Biol. 1983;72(3):213–221. doi: 10.1007/BF01870588. [DOI] [PubMed] [Google Scholar]
- Preisig P. A., Alpern R. J. Chronic metabolic acidosis causes an adaptation in the apical membrane Na/H antiporter and basolateral membrane Na(HCO3)3 symporter in the rat proximal convoluted tubule. J Clin Invest. 1988 Oct;82(4):1445–1453. doi: 10.1172/JCI113750. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Preisig P. A., Ives H. E., Cragoe E. J., Jr, Alpern R. J., Rector F. C., Jr Role of the Na+/H+ antiporter in rat proximal tubule bicarbonate absorption. J Clin Invest. 1987 Oct;80(4):970–978. doi: 10.1172/JCI113190. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Preisig P. A., Rector F. C., Jr Role of Na+-H+ antiport in rat proximal tubule NaCl absorption. Am J Physiol. 1988 Sep;255(3 Pt 2):F461–F465. doi: 10.1152/ajprenal.1988.255.3.F461. [DOI] [PubMed] [Google Scholar]
- RECTOR F. C., Jr, CARTER N. W., SELDIN D. W. THE MECHANISM OF BICARBONATE REABSORPTION IN THE PROXIMAL AND DISTAL TUBULES OF THE KIDNEY. J Clin Invest. 1965 Feb;44:278–290. doi: 10.1172/JCI105142. [DOI] [PMC free article] [PubMed] [Google Scholar]
- RECTOR F. C., Jr, SELDIN D. W., ROBERTS A. D., Jr, SMITH J. S. The role of plasma CO2 tension and carbonic anhydrase activity in the renal reabsorption of bicarbonate. J Clin Invest. 1960 Nov;39:1706–1721. doi: 10.1172/JCI104193. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 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]
- Schild L., Giebisch G., Karniski L. P., Aronson P. S. Effect of formate on volume reabsorption in the rabbit proximal tubule. J Clin Invest. 1987 Jan;79(1):32–38. doi: 10.1172/JCI112803. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Schwartz G. J. Na+-dependent H+ efflux from proximal tubule: evidence for reversible Na+-H+ exchange. Am J Physiol. 1981 Oct;241(4):F380–F385. doi: 10.1152/ajprenal.1981.241.4.F380. [DOI] [PubMed] [Google Scholar]
- Verkman A. S., Alpern R. J. Kinetic transport model for cellular regulation of pH and solute concentration in the renal proximal tubule. Biophys J. 1987 Apr;51(4):533–546. doi: 10.1016/S0006-3495(87)83379-9. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Vieira F. L., Malnic G. Hydrogen ion secretion by rat renal cortical tubules as studied by an antimony microelectrode. Am J Physiol. 1968 Apr;214(4):710–718. doi: 10.1152/ajplegacy.1968.214.4.710. [DOI] [PubMed] [Google Scholar]
- Walter A., Gutknecht J. Monocarboxylic acid permeation through lipid bilayer membranes. J Membr Biol. 1984;77(3):255–264. doi: 10.1007/BF01870573. [DOI] [PubMed] [Google Scholar]
- Welling L. W., Welling D. J. Surface areas of brush border and lateral cell walls in the rabbit proximal nephron. Kidney Int. 1975 Dec;8(6):343–348. doi: 10.1038/ki.1975.125. [DOI] [PubMed] [Google Scholar]
- 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]