J Physiol Society Meetings
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
 QUICK SEARCH:   [advanced]


     


J Physiol Vol 490, Issue Pt 3 pp 623-632
Copyright © 1996 by The Physiological Society
This Article
Right arrow Full Text (PDF)
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Buffin-Meyer, B
Right arrow Articles by Doucet, A
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Buffin-Meyer, B
Right arrow Articles by Doucet, A

Regulation of renal Na+,K(+)-ATPase in rat thick ascending limb during K+ depletion: evidence for modulation of Na+ affinity.

B Buffin-Meyer, S Marsy, C Barlet-Bas, L Cheval, M Younes-Ibrahim, R Rajerison and A Doucet

Laboratoire de Physiologie Cellulaire, Collège de France, Paris.

1. NaCl reabsorption along the loop of Henle is reduced in K(+)-depleted rats. Because Na+,K(+)-ATPase energizes this transport and because K+ depletion is known to induce an upregulation of Na+,K(+)-ATPase in most tissues, the regulation of this enzyme was investigated at the level of single thick ascending limbs of the loop of Henle freshly microdissected from rats fed either a normal (control rats) or a low-K+ diet (LK rats). 2. Within 2 weeks of K+ depletion, Na+,K(+)-ATPase activity and [3H]ouabain binding were increased by 30-50% in the medullary portion of the thick ascending limb (MTAL). 3. Despite this increase in the number of Na+,K(+)-ATPase units, the transport capacity of the Na+,K+ pump, determined by ouabain-sensitive Rb+ uptake in the presence of an extracellular concentration of Rb+ mimicking the kalaemia determined in control (4.0 mM Rb+) and LK rats (2.3 mM Rb+), was reduced in MTAL from LK rats. 4. Inhibition of the Na+,K+ pump was not accounted for by changes in either extracellular K+ or intracellular Na+ concentrations, but by a decrease in the pump affinity for Na+. 5. Because this change in the apparent affinity of the Na+,K+ pump for Na+ was detectable in intact but not in permeabilized MTAL cells, it is probably induced by a rapidly reversible cytosolic factor.




This article has been cited by other articles:


Home page
Am. J. Physiol. Renal Physiol.Home page
A. K. Rajasekaran and S. A. Rajasekaran
Role of Na-K-ATPase in the assembly of tight junctions
Am J Physiol Renal Physiol, September 1, 2003; 285(3): F388 - F396.
[Abstract] [Full Text] [PDF]


Home page
Am. J. Physiol. Cell Physiol.Home page
S. A. Rajasekaran, J. Hu, J. Gopal, R. Gallemore, S. Ryazantsev, D. Bok, and A. K. Rajasekaran
Na,K-ATPase inhibition alters tight junction structure and permeability in human retinal pigment epithelial cells
Am J Physiol Cell Physiol, June 1, 2003; 284(6): C1497 - C1507.
[Abstract] [Full Text] [PDF]


Home page
J. Biol. Chem.Home page
E. Arystarkhova, C. Donnet, N. K. Asinovski, and K. J. Sweadner
Differential Regulation of Renal Na,K-ATPase by Splice Variants of the gamma Subunit
J. Biol. Chem., March 15, 2002; 277(12): 10162 - 10172.
[Abstract] [Full Text] [PDF]




HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
Copyright © 1996 The Physiological Society.