| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
AJP - Renal Physiology, Vol 270, Issue 3 391-F397, Copyright © 1996 by American Physiological Society
ARTICLES |
L. M. Satlin and L. G. Palmer
Department of Pediatrics, Albert Einstein College of Medicine, Bronx, New York 10461, USA.
Net Na+ absorption in microperfused rabbit cortical collecting ducts (CCDs) is low during the 1st wk of postnatal life, increasing substantially thereafter [L. M. Satlin. Am. J. Physiol. 266 (Renal Fluid Electrolyte Physiol. 35): F57-F65, 1994]. To establish whether the low rate of Na+ absorption observed immediately after birth is due to a low apical Na+ permeability of the neonatal principal cell, we used the patch-clamp technique in split-open CCDs isolated from maturing rabbits to estimate conductance, number (N), and open probability (Po) of apical Na+ channels in principal cells. With LiCl in the pipette and a NaCl or potassium gluconate solution, warmed to 37 degrees C, in the bath, inward currents with a conductance of approximately 11 pS (n = 23) were observed in 17% of cell-attached patches at 1 wk, 41% of patches at 2 wk, and 43% of patches at 5 wk. The mean N per patch in the 1st wk (0.22 +/- 0.09; n = 36) was significantly less than that observed in the 2nd (1.38 +/- 0.39; n = 34) and 5th (1.24 +/- 0.37; n = 21) wk of life. Po, studied at positive pipette voltages, was significantly lower in the 1st wk (0.085 +/- 0.035; n = 5) than in the 2nd wk (0.345 +/- 0.063; n = 9) and 5th wk (0.291 +/- 0.058; n = 4). To confirm that the 11-pS channel represented the amiloride-sensitive apical Na+ channel, cell-attached patches in CCDs isolated from 2-wk-old rabbits were studied with 0.5 microM amiloride added to the LiCl pipette solution. Amiloride led to > 90% reductions in mean open and closed times of the 11-pS conductance, consistent with blockade of the channel. These data indicate that N and Po of apical amiloride-sensitive Na+ channels in principal cells increase significantly after birth.
This article has been cited by other articles:
|
|
 |
|
  G. Estilo, W. Liu, N. Pastor-Soler, P. Mitchell, M. D. Carattino, T. R. Kleyman, and L. M. Satlin Effect of aldosterone on BK channel expression in mammalian cortical collecting duct Am J Physiol Renal Physiol, September 1, 2008; 295(3): F780 - F788. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
W. Liu, T. Morimoto, C. Woda, T. R. Kleyman, and L. M. Satlin Ca2+ dependence of flow-stimulated K secretion in the mammalian cortical collecting duct Am J Physiol Renal Physiol, July 1, 2007; 293(1): F227 - F235. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
F. Najjar, H. Zhou, T. Morimoto, J. B. Bruns, H.-S. Li, W. Liu, T. R. Kleyman, and L. M. Satlin Dietary K+ regulates apical membrane expression of maxi-K channels in rabbit cortical collecting duct Am J Physiol Renal Physiol, October 1, 2005; 289(4): F922 - F932. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
E. I. Veizis, C. R. Carlin, and C. U. Cotton Decreased amiloride-sensitive Na+ absorption in collecting duct principal cells isolated from BPK ARPKD mice Am J Physiol Renal Physiol, February 1, 2004; 286(2): F244 - F254. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
C. B. Woda, N. Miyawaki, S. Ramalakshmi, M. Ramkumar, R. Rojas, B. Zavilowitz, T. R. Kleyman, and L. M. Satlin Ontogeny of flow-stimulated potassium secretion in rabbit cortical collecting duct: functional and molecular aspects Am J Physiol Renal Physiol, October 1, 2003; 285(4): F629 - F639. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
L. M. Satlin, S. Sheng, C. B. Woda, and T. R. Kleyman Epithelial Na+ channels are regulated by flow Am J Physiol Renal Physiol, June 1, 2001; 280(6): F1010 - F1018. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
A. R. Constantinescu, J. C. Lane, J. Mak, B. Zavilowitz, and L. M. Satlin Na+-K+-ATPase-mediated basolateral rubidium uptake in the maturing rabbit cortical collecting duct Am J Physiol Renal Physiol, December 1, 2000; 279(6): F1161 - F1168. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
A. Zolotnitskaya and L. M. Satlin Developmental expression of ROMK in rat kidney Am J Physiol Renal Physiol, June 1, 1999; 276(6): F825 - F836. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 F. J. McDonald, B. Yang, R. F. Hrstka, H. A. Drummond, D. E. Tarr, P. B. McCray Jr., J. B. Stokes, M. J. Welsh, and R. A. Williamson Disruption of the beta subunit of the epithelial Na+ channel in mice: Hyperkalemia and neonatal death associated with a pseudohypoaldosteronism phenotype PNAS, February 16, 1999; 96(4): 1727 - 1731. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
S. Watanabe, K. Matsushita, P. B. McCray Jr., and J. B. Stokes Developmental expression of the epithelial Na+ channel in kidney and uroepithelia Am J Physiol Renal Physiol, February 1, 1999; 276(2): F304 - F314. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
S. M. Huber and M. F. Horster Expression of a hypotonic swelling-activated Cl conductance during ontogeny of collecting duct epithelium Am J Physiol Renal Physiol, July 1, 1998; 275(1): F25 - F32. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 V. M. Vehaskari, J. M. Hempe, J. Manning, D. H. Aviles, and M. C. Carmichael Developmental regulation of ENaC subunit mRNA levels in rat kidney Am J Physiol Cell Physiol, June 1, 1998; 274(6): C1661 - C1666. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
S. Huber, B. Schroppel, M. Kretzler, D. Schlondorff, and M. Horster Single cell RT-PCR analysis of ClC-2 mRNA expression in ureteric bud tip Am J Physiol Renal Physiol, May 1, 1998; 274(5): F951 - F957. [Abstract] [Full Text] [PDF]
|
|
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |
