|
|
||||||||
Department of Physiology and Biophysics, University of Southern California Keck School of Medicine, Los Angeles, California
Submitted 22 January 2007 ; accepted in final form 18 July 2007
To determine the effects of long-term angiotensin-converting enzyme inhibition (ACEI) and blood pressure (BP) lowering on renal sodium transporter abundance and distribution in spontaneously hypertensive rats (SHR), 9-wk SHR were treated with enalapril (30 mg·kg–1·day–1) for 4 wk. BP decreased from 156 ± 4 to 96 ± 8 mmHg. Na+/H+ exchanger isoform 3 (NHE3) and Na+-Pi cotransporter type 2 (NaPi2) localized to the body of the microvilli (MV) in normotensive rat strains. In untreated SHR, NHE3 partially retracted from the body to base of the MV and NaPi2 retracted to subapical vesicles. After enalapril treatment of SHR, NHE3 fully retracted to the base of the MV and, by density gradient fractionation, NHE3, NaPi2, dipeptidyl peptidase IV, myosin VI, Na-Cl cotransporter, and cortical Na-K-Cl cotransporter redistributed from low-density (apical enriched) to high-density (endosome enriched) membranes. Enalapril decreased total abundance of myosin VI (to 0.51 ± 0.18 of untreated), ACE (0.67 ± 0.22), and cortical NaPi2 (0.83 ± 0.10). Normalizing SHR BP with HRH (7.5 mg/day hydralazine, 0.15 mg/day reserpine, and 3 mg/day hydrochlorothiazide) did not change Na+ transporter density distribution or abundance. We conclude that lowering BP to normal levels in SHR does not normalize Na+ transporter distribution, rather, chronic ACEI treatment provokes retraction of Na+ transporters and associated proteins from transport-relevant domains of apical membranes and/or reduces their abundance.
hypertension; kidney; Na transporter; ACE inhibitor; triple therapy
This article has been cited by other articles:
![]() |
A. D. M. Riquier-Brison, P. K. K. Leong, K. Pihakaski-Maunsbach, and A. A. McDonough Angiotensin II stimulates trafficking of NHE3, NaPi2, and associated proteins into the proximal tubule microvilli Am J Physiol Renal Physiol, January 1, 2010; 298(1): F177 - F186. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. Blaine, K. Okamura, H. Giral, S. Breusegem, Y. Caldas, A. Millard, N. Barry, and M. Levi PTH-induced internalization of apical membrane NaPi2a: role of actin and myosin VI Am J Physiol Cell Physiol, December 1, 2009; 297(6): C1339 - C1346. [Abstract] [Full Text] [PDF] |
||||
![]() |
A. D. M. Riquier, D. H. Lee, and A. A. McDonough Renal NHE3 and NaPi2 partition into distinct membrane domains Am J Physiol Cell Physiol, April 1, 2009; 296(4): C900 - C910. [Abstract] [Full Text] [PDF] |
||||
![]() |
D. H. Lee, A. D. M. Riquier, L. E. Yang, P. K. K. Leong, A. B. Maunsbach, and A. A. McDonough Acute hypertension provokes acute trafficking of distal tubule Na-Cl cotransporter (NCC) to subapical cytoplasmic vesicles Am J Physiol Renal Physiol, April 1, 2009; 296(4): F810 - F818. [Abstract] [Full Text] [PDF] |
||||
![]() |
C. Kastner, M. Pohl, M. Sendeski, G. Stange, C. A. Wagner, B. Jensen, A. Patzak, S. Bachmann, and F. Theilig Effects of receptor-mediated endocytosis and tubular protein composition on volume retention in experimental glomerulonephritis Am J Physiol Renal Physiol, April 1, 2009; 296(4): F902 - F911. [Abstract] [Full Text] [PDF] |
||||
![]() |
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] |
||||
![]() |
V. K. Madala Halagappa, S. Tiwari, S. Riazi, X. Hu, and C. M. Ecelbarger Chronic candesartan alters expression and activity of NKCC2, NCC, and ENaC in the obese Zucker rat Am J Physiol Renal Physiol, May 1, 2008; 294(5): F1222 - F1231. [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] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |