HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Jentsch, T. J. Articles by Wiederholt, M. Search for Related Content PubMed PubMed Citation Articles by Jentsch, T. J. Articles by Wiederholt, M. Social Bookmarking                      What's this?

J. Biol. Chem., Vol. 260, Issue 29, 15554-15560, Dec, 1985

Kidney epithelial cells of monkey origin (BSC-1) express a sodium bicarbonate cotransport. Characterization by 22Na+ flux measurements

TJ Jentsch, BS Schill, P Schwartz, H Matthes, SK Keller and M Wiederholt

Na movement across the plasma membranes of confluent monolayers of monkey kidney epithelial cells (BSC-1) was studied using 22Na+ uptake and efflux techniques in the presence of 10(-4) M ouabain. In the presence of 28 mM bicarbonate, uptake was inhibited by both 10(-3) M amiloride and 10(-3) M 4,4'diisothiocyanostilbene-2,2'-disulfonic acid (DIDS). In DIDS-pretreated cells, 10(-3) M amiloride led to a further reduction of 22Na+ uptake, while 10(-5) furosemide was ineffective. DIDS also inhibited sodium efflux, indicating that the DIDS-sensitive pathway mediates both influx and efflux of 22Na+. DIDS-sensitive 22Na+ uptake, as studied in the presence of both 10(-4) M ouabain and 10(-3) M amiloride, was abolished by the absence of bicarbonate, which could not be substituted by other plasma membrane-permeable buffers. In 28 mM HCO3-, DIDS-sensitive uptake of 28 mM Na+ was cis-inhibited by 124 mM Na+, but no significant inhibition by K+ or Li+ was found. DIDS- sensitive 22Na+ uptake was a saturable function of both Na+ concentration (apparent Km between 20 and 40 mM at 28 mM HCO3-) and HCO3- concentration (apparent Km between 7 and 14 mM at 151 mM Na+). Intracellular microelectrode measurements showed that net Na+ transport in the presence of HCO3- is electrogenic, i.e. that there is anion cotransport with Na+. This effect is abolished by 1 mM DIDS. It is concluded that monkey kidney epithelial cells possess a stilbene- sensitive, electrogenic sodium bicarbonate symport, which may play an important role in bicarbonate reabsorption in the mammalian kidney.
CiteULike    Complore    Connotea    Del.icio.us    Digg    Reddit    Technorati    What's this?

This article has been cited by other articles:

				M. C. Villa-Abrille, M. G. V. Petroff, and E. A. Aiello The electrogenic Na+/HCO3- cotransport modulates resting membrane potential and action potential duration in cat ventricular myocytes J. Physiol., February 1, 2007; 578(3): 819 - 829. [Abstract] [Full Text] [PDF]

				R. Zhao and R. A. F. Reithmeier Expression and characterization of the anion transporter homologue YNL275w in Saccharomyces cerevisiae Am J Physiol Cell Physiol, July 1, 2001; 281(1): C33 - C45. [Abstract] [Full Text] [PDF]

				U. SEIDLER, H. ROSSMANN, P. JACOB, O. BACHMANN, S. CHRISTIANI, G. LAMPRECHT, and M. GREGOR Expression and Function of Na+HCO3- Cotransporters in the Gastrointestinal Tract Ann. N.Y. Acad. Sci., December 1, 2000; 915(1): 1 - 14. [Abstract] [Full Text] [PDF]