Abstract
The effects of replacing luminal chloride with gluconate on distal tubule bicarbonate transport were studied in vivo in normally fed rats, overnight-fasted rats, and rats made mildly alkalotic by administration of desoxycorticosterone acetate (DOCA). In paired microperfusions of the same tubule with 0 or 55 mM Cl at 25 nl/min, net secretion of bicarbonate by distal tubules of fed rats was inhibited by chloride replacement. Zero chloride perfusion in DOCA rats also resulted in an inhibition of net bicarbonate secretion at 25 nl/min. In contrast, replacement of 45 mM chloride also perfused at 25 nl/min in fasted rats caused an increase in net bicarbonate reabsorption. To further characterize the effects of changes in luminal chloride, experiments were undertaken in fasted rats with 0, 45, and 100 mM chloride-containing solutions perfused at 8 and 25 nl/min. Perfusion with zero Cl resulted in net bicarbonate reabsorption at 8 nl/min that increased markedly with high flow, whereas bicarbonate reabsorption did not change significantly during perfusion at high flow with a 45-mM Cl perfusate. In marked contrast, perfusion with a 100-mM Cl solution resulted in only minimal bicarbonate reabsorption at 8 nl/min with significant secretion observed at high flow. Thus, chloride-free perfusates inhibit bicarbonate secretion and enhance bicarbonate reabsorption, while high chloride perfusates elicit net bicarbonate secretion in usually reabsorbing distal tubules.
Full text
PDFSelected References
These references are in PubMed. This may not be the complete list of references from this article.
- Bichara M., Mercier O., Houillier P., Paillard M., Leviel F. Effects of antidiuretic hormone on urinary acidification and on tubular handling of bicarbonate in the rat. J Clin Invest. 1987 Sep;80(3):621–630. doi: 10.1172/JCI113114. [DOI] [PMC free article] [PubMed] [Google Scholar]
- CLAPP J. R., RECTOR F. C., Jr, SELDIN D. W. Effect of unreabsorbed anions on proximal and distal transtubular potentials in rats. Am J Physiol. 1962 Apr;202:781–786. doi: 10.1152/ajplegacy.1962.202.4.781. [DOI] [PubMed] [Google Scholar]
- Capasso G., Jaeger P., Giebisch G., Guckian V., Malnic G. Renal bicarbonate reabsorption in the rat. II. Distal tubule load dependence and effect of hypokalemia. J Clin Invest. 1987 Aug;80(2):409–414. doi: 10.1172/JCI113087. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Ellison D. H., Velázquez H., Wright F. S. Stimulation of distal potassium secretion by low lumen chloride in the presence of barium. Am J Physiol. 1985 May;248(5 Pt 2):F638–F649. doi: 10.1152/ajprenal.1985.248.5.F638. [DOI] [PubMed] [Google Scholar]
- Galla J. H., Bonduris D. N., Luke R. G. Superficial distal and deep nephrons in correction of metabolic alkalosis. Am J Physiol. 1989 Jul;257(1 Pt 2):F107–F113. doi: 10.1152/ajprenal.1989.257.1.F107. [DOI] [PubMed] [Google Scholar]
- Galla J. H., Luke R. G. Chloride transport and disorders of acid-base balance. Annu Rev Physiol. 1988;50:141–158. doi: 10.1146/annurev.ph.50.030188.001041. [DOI] [PubMed] [Google Scholar]
- Garcia-Austt J., Good D. W., Burg M. B., Knepper M. A. Deoxycorticosterone-stimulated bicarbonate secretion in rabbit cortical collecting ducts: effects of luminal chloride removal and in vivo acid loading. Am J Physiol. 1985 Aug;249(2 Pt 2):F205–F212. doi: 10.1152/ajprenal.1985.249.2.F205. [DOI] [PubMed] [Google Scholar]
- Good D. W., Wright F. S. Luminal influences on potassium secretion: sodium concentration and fluid flow rate. Am J Physiol. 1979 Feb;236(2):F192–F205. doi: 10.1152/ajprenal.1979.236.2.F192. [DOI] [PubMed] [Google Scholar]
- Good D. W., Wright F. S. Luminal influences on potassium secretion: transepithelial voltage. Am J Physiol. 1980 Sep;239(3):F289–F298. doi: 10.1152/ajprenal.1980.239.3.F289. [DOI] [PubMed] [Google Scholar]
- Iacovitti M., Nash L., Peterson L. N., Rochon J., Levine D. Z. Distal tubule bicarbonate accumulation in vivo. Effect of flow and transtubular bicarbonate gradients. J Clin Invest. 1986 Dec;78(6):1658–1665. doi: 10.1172/JCI112759. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Knepper M. A., Good D. W., Burg M. B. Mechanism of ammonia secretion by cortical collecting ducts of rabbits. Am J Physiol. 1984 Nov;247(5 Pt 2):F729–F738. doi: 10.1152/ajprenal.1984.247.5.F729. [DOI] [PubMed] [Google Scholar]
- Kunau R. T., Jr, Walker K. A. Total CO2 absorption in the distal tubule of the rat. Am J Physiol. 1987 Mar;252(3 Pt 2):F468–F473. doi: 10.1152/ajprenal.1987.252.3.F468. [DOI] [PubMed] [Google Scholar]
- Laski M. E., Kurtzman N. A. Characterization of acidification in the cortical and medullary collecting tubule of the rabbit. J Clin Invest. 1983 Dec;72(6):2050–2059. doi: 10.1172/JCI111170. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Laski M. E., Warnock D. G., Rector F. C., Jr Effects of chloride gradients on total CO2 flux in the rabbit cortical collecting tubule. Am J Physiol. 1983 Feb;244(2):F112–F121. doi: 10.1152/ajprenal.1983.244.2.F112. [DOI] [PubMed] [Google Scholar]
- Levine D. Z., Iacovitti M., Nash L., Vandorpe D. Secretion of bicarbonate by rat distal tubules in vivo. Modulation by overnight fasting. J Clin Invest. 1988 Jun;81(6):1873–1878. doi: 10.1172/JCI113533. [DOI] [PMC free article] [PubMed] [Google Scholar]
- McKinney T. D., Burg M. B. Bicarbonate transport by rabbit cortical collecting tubules. Effect of acid and alkali loads in vivo on transport in vitro. J Clin Invest. 1977 Sep;60(3):766–768. doi: 10.1172/JCI108830. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Sansom S. C., Weinman E. J., O'Neil R. G. Microelectrode assessment of chloride-conductive properties of cortical collecting duct. Am J Physiol. 1984 Aug;247(2 Pt 2):F291–F302. doi: 10.1152/ajprenal.1984.247.2.F291. [DOI] [PubMed] [Google Scholar]
- Schuster V. L. Cyclic adenosine monophosphate-stimulated anion transport in rabbit cortical collecting duct. Kinetics, stoichiometry, and conductive pathways. J Clin Invest. 1986 Dec;78(6):1621–1630. doi: 10.1172/JCI112755. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Star R. A., Burg M. B., Knepper M. A. Bicarbonate secretion and chloride absorption by rabbit cortical collecting ducts. Role of chloride/bicarbonate exchange. J Clin Invest. 1985 Sep;76(3):1123–1130. doi: 10.1172/JCI112067. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Steinmetz P. R. Cellular organization of urinary acidification. Am J Physiol. 1986 Aug;251(2 Pt 2):F173–F187. doi: 10.1152/ajprenal.1986.251.2.F173. [DOI] [PubMed] [Google Scholar]
- Vurek G. G., Warnock D. G., Corsey R. Measurement of picomole amounts of carbon dioxide by calorimetry. Anal Chem. 1975 Apr;47(4):765–767. doi: 10.1021/ac60354a024. [DOI] [PubMed] [Google Scholar]