|
|
||||||||
1 Department of Pharmacology, University of Tübingen, D-72074 Tübingen; and 2 Hoechst Marion Roussel, D-65926 Frankfurt am Main, Germany
Na+/H+ exchanger NHE3 is expressed in the luminal membrane of proximal tubule and thin and thick ascending limb of Henle's loop. To further define its role, the novel NHE3 inhibitor S3226 was employed in micropuncture experiments in nephrons with superficial glomeruli of anesthetized rats. Microperfusion of proximal convoluted tubule with S3226 revealed a dose-dependent inhibition of reabsorption (IC50 of 4-5 µM) with a maximum inhibition of 30% for fluid and Na+. During microperfusion of Henle's loop (last superficial proximal to first superficial distal tubular loop), no effect of S3226 (10 or 30 µM) on the reabsorption of fluid or Na+ was observed. Finally, S3226 (30 µM) left the tubuloglomerular feedback response unaltered as determined by the fall in proximal tubular stop-flow pressure in response to increasing loop of Henle perfusion rate. These studies indicate that NHE3 significantly contributes to fluid and Na+ reabsorption in proximal convoluted tubule. NHE3 appears not to significantly contribute to fluid or Na+ reabsorption in the loop of Henle (including the S3 segment of proximal tubule) or macula densa control of nephron filtration.
reabsorption; proximal tubule; loop of Henle; tubuloglomerular feedback
This article has been cited by other articles:
![]() |
L. E. Yang, M. B. Sandberg, A. D. Can, K. Pihakaski-Maunsbach, and A. A. McDonough Effects of dietary salt on renal Na+ transporter subcellular distribution, abundance, and phosphorylation status Am J Physiol Renal Physiol, October 1, 2008; 295(4): F1003 - F1016. [Abstract] [Full Text] [PDF] |
||||
![]() |
P. L. Diaz-Sylvester, M. C. Fiori, S. M. Dieguez, A. C. Muller, M. L. Lopardo, and C. E. Amorena Effect of chronic inhibition of converting enzyme on proximal tubule acidification Am J Physiol Regulatory Integrative Comp Physiol, June 1, 2008; 294(6): R2014 - R2020. [Abstract] [Full Text] [PDF] |
||||
![]() |
C. N. A. Bezerra, A. C. C. Girardi, L. R. Carraro-Lacroix, and N. A. Reboucas Mechanisms underlying the long-term regulation of NHE3 by parathyroid hormone Am J Physiol Renal Physiol, May 1, 2008; 294(5): F1232 - F1237. [Abstract] [Full Text] [PDF] |
||||
![]() |
A. C. C. Girardi, L. E. Fukuda, L. V. Rossoni, G. Malnic, and N. A. Reboucas Dipeptidyl peptidase IV inhibition downregulates Na+-H+ exchanger NHE3 in rat renal proximal tubule Am J Physiol Renal Physiol, February 1, 2008; 294(2): F414 - F422. [Abstract] [Full Text] [PDF] |
||||
![]() |
V. Vallon, B. Muhlbauer, and H. Osswald Adenosine and kidney function. Physiol Rev, July 1, 2006; 86(3): 901 - 940. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. Mizumori, J. Meyerowitz, T. Takeuchi, S. Lim, P. Lee, C. T. Supuran, P. H. Guth, E. Engel, J. D. Kaunitz, and Y. Akiba Epithelial carbonic anhydrases facilitate PCO2 and pH regulation in rat duodenal mucosa J. Physiol., June 15, 2006; 573(3): 827 - 842. [Abstract] [Full Text] [PDF] |
||||
![]() |
K. P. Choe, A. Kato, S. Hirose, C. Plata, A. Sindic, M. F. Romero, J. B. Claiborne, and D. H. Evans NHE3 in an ancestral vertebrate: primary sequence, distribution, localization, and function in gills Am J Physiol Regulatory Integrative Comp Physiol, November 1, 2005; 289(5): R1520 - R1534. [Abstract] [Full Text] [PDF] |
||||
![]() |
O. Furukawa, M. Hirokawa, L. Zhang, T. Takeuchi, L. C. Bi, P. H. Guth, E. Engel, Y. Akiba, and J. D. Kaunitz Mechanism of augmented duodenal HCO3- secretion after elevation of luminal CO2 Am J Physiol Gastrointest Liver Physiol, March 1, 2005; 288(3): G557 - G563. [Abstract] [Full Text] [PDF] |
||||
![]() |
V. Vallon, P. Wulff, D. Y. Huang, J. Loffing, H. Volkl, D. Kuhl, and F. Lang Role of Sgk1 in salt and potassium homeostasis Am J Physiol Regulatory Integrative Comp Physiol, January 1, 2005; 288(1): R4 - R10. [Abstract] [Full Text] [PDF] |
||||
![]() |
A. C. C. Girardi, F. Knauf, H.-U. Demuth, and P. S. Aronson Role of dipeptidyl peptidase IV in regulating activity of Na+/H+ exchanger isoform NHE3 in proximal tubule cells Am J Physiol Cell Physiol, November 1, 2004; 287(5): C1238 - C1245. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. Graebe, L. Brond, S. Christensen, S. Nielsen, N. V. Olsen, and T. E. N. Jonassen Chronic nitric oxide synthase inhibition exacerbates renal dysfunction in cirrhotic rats Am J Physiol Renal Physiol, February 1, 2004; 286(2): F288 - F297. [Abstract] [Full Text] [PDF] |
||||
![]() |
O. Furukawa, L. C. Bi, P. H. Guth, E. Engel, M. Hirokawa, and J. D. Kaunitz NHE3 inhibition activates duodenal bicarbonate secretion in the rat Am J Physiol Gastrointest Liver Physiol, January 1, 2004; 286(1): G102 - G109. [Abstract] [Full Text] [PDF] |
||||
![]() |
X.F. Wang, M.K. Yu, S.Y. Lam, K.M. Leung, J.L. Jiang, P.S. Leung, W.H. Ko, P.Y. Leung, S.B.C. Chew, C.Q. Liu, et al. Expression, Immunolocalization, and Functional Activity of Na+/H+ Exchanger Isoforms in Mouse Endometrial Epithelium Biol Reprod, January 1, 2003; 68(1): 302 - 308. [Abstract] [Full Text] [PDF] |
||||
![]() |
C. Hill, A. N. Giesberts, and S. J. White Expression of isoforms of the Na+/H+ exchanger in M-1 mouse cortical collecting duct cells Am J Physiol Renal Physiol, April 1, 2002; 282(4): F649 - F654. [Abstract] [Full Text] [PDF] |
||||
![]() |
T. Wang, M. Hropot, P. S. Aronson, and G. Giebisch Role of NHE isoforms in mediating bicarbonate reabsorption along the nephron Am J Physiol Renal Physiol, December 1, 2001; 281(6): F1117 - F1122. [Abstract] [Full Text] [PDF] |
||||
![]() |
A. Khadilkar, P. Iannuzzi, and J. Orlowski Identification of Sites in the Second Exomembrane Loop and Ninth Transmembrane Helix of the Mammalian Na+/H+ Exchanger Important for Drug Recognition and Cation Translocation J. Biol. Chem., November 16, 2001; 276(47): 43792 - 43800. [Abstract] [Full Text] [PDF] |
||||
![]() |
F. Knauf, C.-L. Yang, R. B. Thomson, S. A. Mentone, G. Giebisch, and P. S. Aronson Identification of a chloride-formate exchanger expressed on the brush border membrane of renal proximal tubule cells PNAS, July 31, 2001; 98(16): 9425 - 9430. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |