|
|
||||||||
1 Departments of Pediatrics, 2 Anesthesiology, and 3 Biostatistics, University of Alabama at Birmingham, Birmingham Alabama 35226
Regulation of active Na+
transport across fetal distal lung epithelial cells (FDLE) by
corticosterone (CST), corticotropin-releasing hormone (CRH), and oxygen
tension may be crucial for postnatal adaptation. FDLE isolated from
19-day rat fetuses (term: 22 days) were grown on permeable supports to
confluent monolayers (duration 3 days) in 2.5, 5, 12, or 20%
O2 with 5% CO2-balance N2 and
mounted in Ussing chambers for measurement of short-circuit currents
(Isc). FDLE monolayers grown in 20%
O2 had significantly higher levels of total
Isc and of their amiloride-sensitive
(Iamil) and ouabain-sensitive (Iouab) components than hypoxic cells. Values
(µA/cm2 ± SE) for 2.5-5% O2 and
20% O2 were, respectively, Isc
5.3 ± 0.2 vs. 8.4 ± 0.3 (P < 0.001),
Iamil 3.4 ± 0.2 vs. 4.3 ± 0.2 (P < 0.01), and Iouab 3.4 ± 0.6 vs. 9.1 ± 0.6 (P < 0.001). Addition of
CST but not CRH to the culture medium at any O2
concentration increased Iamil. FDLE cells grown
at 5% O2 expressed significantly lower levels of
-,
-, and
-epithelial Na+ channel (ENaC), and of the
1-Na+-K+-ATPase, as determined
by Western blotting. We conclude that higher O2
concentrations increased total vectorial Na+ transport, and
the function of Na+-K+-ATPase and apical
amiloride-sensitive Na+ conductance, whereas CST only
increased ENaC function.
Ussing chamber; short-circuit current; sodium-potassium-adenosinetriphosphatase; epithelial sodium channel; oxygen; corticosterone; corticotropin-releasing hormone
This article has been cited by other articles:
![]() |
H.-G. Nie, L. Chen, D.-Y. Han, J. Li, W.-F. Song, S.-P. Wei, X.-H. Fang, X. Gu, S. Matalon, and H.-L. Ji Regulation of epithelial sodium channels by cGMP/PKGII J. Physiol., June 1, 2009; 587(11): 2663 - 2676. [Abstract] [Full Text] [PDF] |
||||
![]() |
H.-G. Nie, T. Tucker, X.-F. Su, T. Na, J.-B. Peng, P. R. Smith, S. Idell, and H.-L. Ji Expression and Regulation of Epithelial Na+ Channels by Nucleotides in Pleural Mesothelial Cells Am. J. Respir. Cell Mol. Biol., May 1, 2009; 40(5): 543 - 554. [Abstract] [Full Text] [PDF] |
||||
![]() |
S. X. L. Zhang, J. J. Miller, D. B. Stolz, L. D. Serpero, W. Zhao, D. Gozal, and Y. Wang Type I Epithelial Cells Are the Main Target of Whole-Body Hypoxic Preconditioning in the Lung Am. J. Respir. Cell Mol. Biol., March 1, 2009; 40(3): 332 - 339. [Abstract] [Full Text] [PDF] |
||||
![]() |
V. Bhalla and K. R. Hallows Mechanisms of ENaC Regulation and Clinical Implications J. Am. Soc. Nephrol., October 1, 2008; 19(10): 1845 - 1854. [Abstract] [Full Text] [PDF] |
||||
![]() |
L. Yu, H.-F. Bao, J. L. Self, D. C. Eaton, and M. N. Helms Aldosterone-induced increases in superoxide production counters nitric oxide inhibition of epithelial Na channel activity in A6 distal nephron cells Am J Physiol Renal Physiol, November 1, 2007; 293(5): F1666 - F1677. [Abstract] [Full Text] [PDF] |
||||
![]() |
V. Bhalla, N. M. Oyster, A. C. Fitch, M. A. Wijngaarden, D. Neumann, U. Schlattner, D. Pearce, and K. R. Hallows AMP-activated Kinase Inhibits the Epithelial Na+ Channel through Functional Regulation of the Ubiquitin Ligase Nedd4-2 J. Biol. Chem., September 8, 2006; 281(36): 26159 - 26169. [Abstract] [Full Text] [PDF] |
||||
![]() |
G. Otulakowski, B. Rafii, M. Harris, and H. O'Brodovich Oxygen and Glucocorticoids Modulate {alpha}ENaC mRNA Translation in Fetal Distal Lung Epithelium Am. J. Respir. Cell Mol. Biol., February 1, 2006; 34(2): 204 - 212. [Abstract] [Full Text] [PDF] |
||||
![]() |
K. M. Hardiman, C. M. McNicholas-Bevensee, J. Fortenberry, C. T. Myles, B. Malik, D. C. Eaton, and S. Matalon Regulation of Amiloride-Sensitive Na+ Transport by Basal Nitric Oxide Am. J. Respir. Cell Mol. Biol., May 1, 2004; 30(5): 720 - 728. [Abstract] [Full Text] [PDF] |
||||
![]() |
O. A. Weisz and J. P. Johnson Noncoordinate regulation of ENaC: paradigm lost? Am J Physiol Renal Physiol, November 1, 2003; 285(5): F833 - F842. [Abstract] [Full Text] [PDF] |
||||
![]() |
D. L. Mandell, D. C. Devor, J. V. Madia, C.-Y. Lo, H. Hake, and P. A. Hebda The effect of changes in ambient oxygen concentration on the bioelectric properties of middle ear mucosa Am J Physiol Cell Physiol, September 1, 2003; 285(3): C618 - C622. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |