| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
AJP - Cell Physiology, Vol 271, Issue 5 C1629-C1638, Copyright © 1996 by American Physiological Society
ARTICLES |
C. Bookstein, M. W. Musch, A. DePaoli, Y. Xie, K. Rabenau, M. Villereal, M. C. Rao and E. B. Chang
Department of Medicine, University of Chicago 60637, USA.
The kinetics of the Na+/H+ exchanger (NHE) isoform NHE4 were studied by measuring 22Na+ fluxes in stably transfected NHE-deficient fibroblasts. Unlike NHE1, NHE2, and NHE3, activation of this isoform is dependent on hyperosmolarity-induced cell shrinkage. It is virtually inactive at isosmolarity and most active at 490 mosM. When induced by cell shrinkage, NHE4 exhibits a sigmoidal response to increasing extracellular Na+ concentrations, suggesting allosteric or cooperative binding kinetics. In comparison, NHE1 and -3 exhibit hyperbolic velocity vs. extracellular Na+ concentration responses at both iso- and hyperosmolar conditions. Unlike NHE1 and NHE4, hyperosmolarity-induced cell shrinkage inhibits NHE3 activity in transfected fibroblasts, reducing maximum velocity by 40%, with no effect on binding affinity to extracellular Na+.NHE4 is relatively insensitive to inhibition by amiloride analogues in the order 5-(N,N-dimethyl)amiloride > 5-(N,N-hexamethylene)amiloride ride > amiloride > 5-(N-ethyl-N-isopropyl)amiloride. Time-dependent inhibition of activity by cytochalasin D suggests a relationship between the actin cytoskeleton and regulation by cell shrinkage. By in situ hybridization of fixed tissues, NHE4 mRNA was found to be highly expressed in the cavi amnoni fields of rat hippocampus. The kinetics of this exchanger, when considered with its unusual tissue distribution in renal inner medullary collecting tubules and hippocampus, are-consistent with NHE4 having a specialized role in cell functions.
This article has been cited by other articles:
|
|
 |
|
  O. Bachmann, A. Heinzmann, A. Mack, M. P. Manns, and U. Seidler Mechanisms of secretion-associated shrinkage and volume recovery in cultured rabbit parietal cells Am J Physiol Gastrointest Liver Physiol, March 1, 2007; 292(3): G711 - G717. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
H. Xu, R. Chen, and F. K. Ghishan Subcloning, localization, and expression of the rat intestinal sodium-hydrogen exchanger isoform 8 Am J Physiol Gastrointest Liver Physiol, July 1, 2005; 289(1): G36 - G41. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 M. CHESLER Regulation and Modulation of pH in the Brain Physiol Rev, October 1, 2003; 83(4): 1183 - 1221. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 E.A. Harding, C.A. Gibb, M.H. Johnson, D.I. Cook, and M.L. Day Developmental Changes in the Management of Acid Loads During Preimplantation Mouse Development Biol Reprod, November 1, 2002; 67(5): 1419 - 1429. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 Y. Miyata, Y. Asano, and S. Muto Hyperosmotic urea activates basolateral NHE in proximal tubule from P-gp null and wild-type mice Am J Physiol Renal Physiol, October 1, 2002; 283(4): F771 - F783. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 S. Attaphitaya, K. Nehrke, and J. E. Melvin Acute inhibition of brain-specific Na+/H+ exchanger isoform 5 by protein kinases A and C and cell shrinkage Am J Physiol Cell Physiol, October 1, 2001; 281(4): C1146 - C1157. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
H. Yao, X.-Q. Gu, R. M. Douglas, and G. G. Haddad Role of Na+/H+ exchanger during O2 deprivation in mouse CA1 neurons Am J Physiol Cell Physiol, October 1, 2001; 281(4): C1205 - C1210. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
R. Chambrey, P. L. St. John, D. Eladari, F. Quentin, D. G. Warnock, D. R. Abrahamson, R.-A. Podevin, and M. Paillard Localization and functional characterization of Na+/H+ exchanger isoform NHE4 in rat thick ascending limbs Am J Physiol Renal Physiol, October 1, 2001; 281(4): F707 - F717. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
H. Rossmann, T. Sonnentag, A. Heinzmann, B. Seidler, O. Bachmann, D. Vieillard-Baron, M. Gregor, and U. Seidler Differential expression and regulation of Na+/H+ exchanger isoforms in rabbit parietal and mucous cells Am J Physiol Gastrointest Liver Physiol, August 1, 2001; 281(2): G447 - G458. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. Peti-Peterdi, R. Chambrey, Z. Bebok, D. Biemesderfer, P. L. St. John, D. R. Abrahamson, D. G. Warnock, and P. D. Bell Macula densa Na+/H+ exchange activities mediated by apical NHE2 and basolateral NHE4 isoforms Am J Physiol Renal Physiol, March 1, 2000; 278(3): F452 - F463. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 E. Z. Szabo, M. Numata, G. E. Shull, and J. Orlowski Kinetic and Pharmacological Properties of Human Brain Na+/H+ Exchanger Isoform 5 Stably Expressed in Chinese Hamster Ovary Cells J. Biol. Chem., February 25, 2000; 275(9): 6302 - 6307. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
L. Counillon and J. Pouyssegur The Expanding Family of Eucaryotic Na+/H+ Exchangers J. Biol. Chem., January 7, 2000; 275(1): 1 - 4. [Full Text] [PDF]
|
|
|
|
|
|
N. R. Baird, J. Orlowski, E. Z. Szabo, H. C. Zaun, P. J. Schultheis, A. G. Menon, and G. E. Shull Molecular Cloning, Genomic Organization, and Functional Expression of Na+/H+ Exchanger Isoform 5 (NHE5) from Human Brain J. Biol. Chem., February 12, 1999; 274(7): 4377 - 4382. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
S. Attaphitaya, K. Park, and J. E. Melvin Molecular Cloning and Functional Expression of a Rat Na+/H+ Exchanger (NHE5) Highly Expressed in Brain J. Biol. Chem., February 12, 1999; 274(7): 4383 - 4388. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 A. K. Howe, S. Gaillard, J. S. Bennett, and K. Rundell Cell Cycle Progression in Monkey Cells Expressing Simian Virus 40 Small t Antigen from Adenovirus Vectors J. Virol., December 1, 1998; 72(12): 9637 - 9644. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
O. Bachmann, T. Sonnentag, W.-K. Siegel, G. Lamprecht, A. Weichert, M. Gregor, and U. Seidler Different acid secretagogues activate different Na+/H+ exchanger isoforms in rabbit parietal cells Am J Physiol Gastrointest Liver Physiol, November 1, 1998; 275(5): G1085 - G1093. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
R. L. McSwine, M. W. Musch, C. Bookstein, Y. Xie, M. Rao, and E. B. Chang Regulation of apical membrane Na+/H+ exchangers NHE2 and NHE3 in intestinal epithelial cell line C2/bbe Am J Physiol Cell Physiol, September 1, 1998; 275(3): C693 - C701. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
F. LANG, G. L. BUSCH, M. RITTER, H. VOLKL, S. WALDEGGER, E. GULBINS, and D. HAUSSINGER Functional Significance of Cell Volume Regulatory Mechanisms Physiol Rev, January 1, 1998; 78(1): 247 - 306. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
C. Bookstein, Y. Xie, K. Rabenau, M. W. Musch, R. L. McSwine, M. C. Rao, and E. B. Chang Tissue distribution of Na+/H+ exchanger isoforms NHE2 and NHE4 in rat intestine and kidney Am J Physiol Cell Physiol, November 1, 1997; 273(5): C1496 - C1505. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. Orlowski and S. Grinstein Na+/H+ Exchangers of Mammalian Cells J. Biol. Chem., September 5, 1997; 272(36): 22373 - 22376. [Full Text] [PDF]
|
|
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |
