| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
-ENaC and
1-Na+-K+-ATPase by cAMP and
dexamethasone in alveolar epithelial cells
1 Département de Médecine, Centre de Recherche, Centre Hospitalier de l'Université de Montréal-Hôtel-Dieu, Université de Montréal, Montreal, Quebec H2W 1T8; and 2 Centre for Molecular Medicine, Ottawa General Hospital Research Institute, Ottawa, Ontario K1H 8L5, Canada
cAMP and
dexamethasone are known to modulate Na+ transport in
epithelial cells. We investigated whether dibutyryl cAMP (DBcAMP) and
dexamethasone modulate the mRNA expression of two key elements of the
Na+ transport system in isolated rat alveolar epithelial
cells: 
-, 
-, and 
-subunits of the epithelial Na+
channel (ENaC) and the 1- and 1-subunits
of Na+-K+-ATPase. The cells were treated for up
to 48 h with DBcAMP or dexamethasone to assess their long-term
impact on the steady-state level of ENaC and
Na+-K+-ATPase mRNA. DBcAMP induced a twofold
transient increase of -ENaC and
1-Na+-K+-ATPase mRNA that peaked
after 8 h of treatment. It also upregulated - and -ENaC mRNA
but not 1-Na+-K+-ATPase mRNA.
Dexamethasone augmented -ENaC mRNA expression 4.4-fold in cells
treated for 24 h and also upregulated - and -ENaC mRNA. There was a 1.6-fold increase at 8 h of
1-Na+-K+-ATPase mRNA but no
significant modulation of
1-Na+-K+-ATPase mRNA expression.
Because DBcAMP and dexamethasone did not increase the stability of
-ENaC mRNA, we cloned 3.2 kb of the 5' sequences flanking the mouse
-ENaC gene to study the impact of DBcAMP and dexamethasone
on -ENaC promoter activity. The promoter was able to
drive basal expression of the chloramphenicol acetyltransferase (CAT)
reporter gene in A549 cells. Dexamethasone increased the activity of
the promoter by a factor of 5.9. To complete the study, the
physiological effects of DBcAMP and dexamethasone were investigated by
measuring transepithelial current in treated and control cells. DBcAMP
and dexamethasone modulated transepithelial current with a time course
reminiscent of the profile observed for -ENaC mRNA expression.
DBcAMP had a greater impact on transepithelial current (2.5-fold
increase at 8 h) than dexamethasone (1.8-fold increase at 24 h). These results suggest that modulation of -ENaC and Na+-K+-ATPase gene expression is one of the
mechanisms that regulates Na+ transport in alveolar
epithelial cells.
sodium channel; adenosine 3',5'-cyclic monophosphate; steroid; sodium-potassium-adenosinetriphosphatase; transepithelial current; epithelial sodium channel
This article has been cited by other articles:
|
|
 |
|
  M. M. Vasquez, S. B. Mustafa, A. Choudary, S. R. Seidner, and R. Castro Regulation of Epithelial Na+ Channel (ENaC) in the Salivary Cell Line SMG-C6 Experimental Biology and Medicine, May 1, 2009; 234(5): 522 - 531. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 S. H. Kim, K. X. Kim, N. N. Raveendran, T. Wu, S. R. Pondugula, and D. C. Marcus Regulation of ENaC-mediated sodium transport by glucocorticoids in Reissner's membrane epithelium Am J Physiol Cell Physiol, March 1, 2009; 296(3): C544 - C557. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 J. Chen, E. Lecuona, A. Briva, L. C. Welch, and J. I. Sznajder Carbonic Anhydrase II and Alveolar Fluid Reabsorption during Hypercapnia Am. J. Respir. Cell Mol. Biol., January 1, 2008; 38(1): 32 - 37. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 S. Guney, A. Schuler, A. Ott, S. Hoschele, S. Zugel, E. Baloglu, P. Bartsch, and H. Mairbaurl Dexamethasone prevents transport inhibition by hypoxia in rat lung and alveolar epithelial cells by stimulating activity and expression of Na+-K+-ATPase and epithelial Na+ channels Am J Physiol Lung Cell Mol Physiol, November 1, 2007; 293(5): L1332 - L1338. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
G. Otulakowski, W. Duan, S. Gandhi, and H. O'Brodovich Steroid and Oxygen Effects on eIF4F Complex, mTOR, and ENaC Translation in Fetal Lung Epithelia Am. J. Respir. Cell Mol. Biol., October 1, 2007; 37(4): 457 - 466. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
T. Li, S. Koshy, and H. G. Folkesson Involvement of {alpha}ENaC and Nedd4-2 in the conversion from lung fluid secretion to fluid absorption at birth in the rat as assayed by RNA interference analysis Am J Physiol Lung Cell Mol Physiol, October 1, 2007; 293(4): L1069 - L1078. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
A. Dagenais, R. Frechette, M.-E. Clermont, C. Masse, A. Prive, E. Brochiero, and Y. Berthiaume Dexamethasone inhibits the action of TNF on ENaC expression and activity Am J Physiol Lung Cell Mol Physiol, December 1, 2006; 291(6): L1220 - L1231. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
H. G. Folkesson and M. A. Matthay Alveolar Epithelial Ion and Fluid Transport: Recent Progress Am. J. Respir. Cell Mol. Biol., July 1, 2006; 35(1): 10 - 19. [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]
|
|
|
|
 |
|
 S. R. Pondugula, N. N. Raveendran, Z. Ergonul, Y. Deng, J. Chen, J. D. Sanneman, L. G. Palmer, and D. C. Marcus Glucocorticoid regulation of genes in the amiloride-sensitive sodium transport pathway by semicircular canal duct epithelium of neonatal rat Physiol Genomics, January 12, 2006; 24(2): 114 - 123. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
G. M. Mutlu and J. I. Sznajder Mechanisms of pulmonary edema clearance Am J Physiol Lung Cell Mol Physiol, November 1, 2005; 289(5): L685 - L695. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
C. P. Thomas, J. R. Campbell, P. J. Wright, and R. F. Husted cAMP-stimulated Na+ transport in H441 distal lung epithelial cells: role of PKA, phosphatidylinositol 3-kinase, and sgk1 Am J Physiol Lung Cell Mol Physiol, October 1, 2004; 287(4): L843 - L851. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
E. Brochiero, A. Dagenais, A. Prive, Y. Berthiaume, and R. Grygorczyk Evidence of a functional CFTR Cl- channel in adult alveolar epithelial cells Am J Physiol Lung Cell Mol Physiol, August 1, 2004; 287(2): L382 - L392. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
S. J. Ramminger, K. Richard, S. K. Inglis, S. C. Land, R. E. Olver, and S. M. Wilson A regulated apical Na+ conductance in dexamethasone-treated H441 airway epithelial cells Am J Physiol Lung Cell Mol Physiol, August 1, 2004; 287(2): L411 - L419. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
G. Otulakowski, B. Rafii, and H. O'Brodovich Differential Translational Efficiency of ENaC Subunits During Lung Development Am. J. Respir. Cell Mol. Biol., June 1, 2004; 30(6): 862 - 870. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 S. R. Pondugula, J. D. Sanneman, P. Wangemann, P. G. Milhaud, and D. C. Marcus Glucocorticoids stimulate cation absorption by semicircular canal duct epithelium via epithelial sodium channel Am J Physiol Renal Physiol, June 1, 2004; 286(6): F1127 - F1135. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
A. Dagenais, R. Frechette, Y. Yamagata, T. Yamagata, J.-F. Carmel, M.-E. Clermont, E. Brochiero, C. Masse, and Y. Berthiaume Downregulation of ENaC activity and expression by TNF-{alpha} in alveolar epithelial cells Am J Physiol Lung Cell Mol Physiol, February 1, 2004; 286(2): L301 - L311. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
B. C. Willis, K.-J. Kim, X. Li, J. Liebler, E. D. Crandall, and Z. Borok Modulation of ion conductance and active transport by TGF-{beta}1 in alveolar epithelial cell monolayers Am J Physiol Lung Cell Mol Physiol, December 1, 2003; 285(6): L1192 - L1200. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
Y. Berthiaume Long-term stimulation of alveolar epithelial cells by {beta}-adrenergic agonists: increased Na+ transport and modulation of cell growth? Am J Physiol Lung Cell Mol Physiol, October 1, 2003; 285(4): L798 - L801. [Full Text] [PDF]
|
|
|
|
|
|
S. M. O'Grady and S. Y. Lee Chloride and potassium channel function in alveolar epithelial cells Am J Physiol Lung Cell Mol Physiol, May 1, 2003; 284(5): L689 - L700. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 Y. Berthiaume, H. G. Folkesson, and M. A. Matthay Lung Edema Clearance: 20 Years of Progress: Invited Review: Alveolar edema fluid clearance in the injured lung J Appl Physiol, December 1, 2002; 93(6): 2207 - 2213. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
L. W. Gonzales, S. H. Guttentag, K. C. Wade, A. D. Postle, and P. L. Ballard Differentiation of human pulmonary type II cells in vitro by glucocorticoid plus cAMP Am J Physiol Lung Cell Mol Physiol, November 1, 2002; 283(5): L940 - L951. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
M. A. Matthay, C. Clerici, and G. Saumon Lung Edema Clearance: 20 Years of Progress: Invited Review: Active fluid clearance from the distal air spaces of the lung J Appl Physiol, October 1, 2002; 93(4): 1533 - 1541. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 M. A. Matthay, H. G. Folkesson, and C. Clerici Lung Epithelial Fluid Transport and the Resolution of Pulmonary Edema Physiol Rev, July 1, 2002; 82(3): 569 - 600. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
M. A. Matthay Editorial: Alveolar Epithelial Ion and Fluid Transport: Regulation of ion and fluid transport across the distal pulmonary epithelia: new insights Am J Physiol Lung Cell Mol Physiol, April 1, 2002; 282(4): L595 - L598. [Full Text] [PDF]
|
|
|
|
|
|
J. D. Stockand New ideas about aldosterone signaling in epithelia Am J Physiol Renal Physiol, April 1, 2002; 282(4): F559 - F576. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
O. A. Itani, S. D. Auerbach, R. F. Husted, K. A. Volk, S. Ageloff, M. A. Knepper, J. B. Stokes, and C. P. Thomas Alveolar Epithelial Ion and Fluid Transport: Glucocorticoid-stimulated lung epithelial Na+ transport is associated with regulated ENaC and sgk1 expression Am J Physiol Lung Cell Mol Physiol, April 1, 2002; 282(4): L631 - L641. [Abstract] [Full Text] [PDF]
|
|
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |
