AJP - Renal Physiology, Vol 264, Issue 6 1021-F1026, Copyright © 1993 by American Physiological Society

ARTICLES

Acute and early effects of aldosterone on Na-K-ATPase activity in Madin-Darby canine kidney epithelial cells

M. Shahedi, K. Laborde, L. Bussieres and C. Sachs
Departement de Physiologie, Faculte de Medecine, Necker Enfants Malades, Paris, France.

The time course and mechanism of early effects of aldosterone on renal Na-K-adenosinetriphosphatase (Na-K-ATPase) activity and number of units were studied in MDCK cells. Aldosterone induced a time- and dose-dependent stimulation of Na-K-ATPase activity. The stimulatory effect of aldosterone on activity and number of pump units increased progressively and was inhibited by spironolactone. In presence of cycloheximide, the stimulatory effect of aldosterone on activity and number of catalytic sites persisted to the same extent until 30 min and decreased by 20% after 60 min. In these cells, dimethylamiloride addition during preincubation abolished the aldosterone-induced stimulation in Na-K-ATPase activity up to 60 min. In contrast, furosemide addition did not alter the effect of aldosterone on Na-K-ATPase activity. The present study demonstrates an early effect of aldosterone on Na-K-ATPase activity that can be separated into the following two successive periods: 1) increase in pump number due to insertion of presynthetized units secondary to Na entry through an amiloride-sensitive apical pathway; and 2) an increase in pump number by de novo protein synthesis.

This article has been cited by other articles:

				M. B. Butterworth, R. S. Edinger, R. A. Frizzell, and J. P. Johnson Regulation of the epithelial sodium channel by membrane trafficking Am J Physiol Renal Physiol, January 1, 2009; 296(1): F10 - F24. [Abstract] [Full Text] [PDF]

				D. W. Good Nongenomic Actions of Aldosterone on the Renal Tubule Hypertension, April 1, 2007; 49(4): 728 - 739. [Full Text] [PDF]

				B. Kreft, W. J. Jabs, T. Laskay, M. Klinger, W. Solbach, S. Kumar, and G. van Zandbergen Polarized Expression of Tamm-Horsfall Protein by Renal Tubular Epithelial Cells Activates Human Granulocytes Infect. Immun., May 1, 2002; 70(5): 2650 - 2656. [Abstract] [Full Text] [PDF]

				A. G. Therien and R. Blostein Mechanisms of sodium pump regulation Am J Physiol Cell Physiol, September 1, 2000; 279(3): C541 - C566. [Abstract] [Full Text] [PDF]

				S. I. Helman, X. Liu, K. Baldwin, B. L. Blazer-Yost, and W. J. Els Time-dependent stimulation by aldosterone of blocker-sensitive ENaCs in A6 epithelia Am J Physiol Cell Physiol, April 1, 1998; 274(4): C947 - C957. [Abstract] [Full Text] [PDF]

				R. A. Shimkets, R. Lifton, and C. M. Canessa In vivo phosphorylation of the epithelial sodium channel PNAS, March 17, 1998; 95(6): 3301 - 3305. [Abstract] [Full Text] [PDF]

				M. Ferrandi, G. Tripodi, S. Salardi, M. Florio, R. Modica, P. Barassi, P. Parenti, A. Shainskaya, S. Karlish, G. Bianchi, et al. Renal Na,K-ATPase in Genetic Hypertension Hypertension, December 1, 1996; 28(6): 1018 - 1025. [Abstract] [Full Text]