AJP - Renal Fuel your research with LabChart
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
QUICK SEARCH:   [advanced]


     

Am J Physiol Renal Physiol 267: F347-F353, 1994;
0363-6127/94 $5.00
This Article
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Okusa, M. D.
Right arrow Articles by Wei, Y. Y.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Okusa, M. D.
Right arrow Articles by Wei, Y. Y.

AJP - Renal Physiology, Vol 267, Issue 3 347-F353, Copyright © 1994 by American Physiological Society

ARTICLES

Apical membrane and intracellular distribution of endogenous alpha 2A-adrenergic receptors in MDCK cells

M. D. Okusa, K. R. Lynch, D. L. Rosin, L. Huang and Y. Y. Wei
Department of Medicine, University of Virginia Health Sciences Center, Charlottesville 22908.

The purpose of the current studies was to characterize the endogenous alpha 2-adrenergic receptor (AR) subtypes present in Madin-Darby canine kidney (MDCK) cells and to determine their level of expression and pattern of distribution. By saturation binding analysis with [3H]MK-912, MDCK cells expressed high levels of alpha 2-ARs with a maximum receptor density (Bmax) of 798 +/- 55 fmol/mg protein and an equilibrium dissociation constant (Kd) of 0.98 +/- 0.32 nM. Competitive binding studies using prazosin, oxymetazoline, phentolamine, and epinephrine to displace [3H]MK-912 demonstrated inhibition constant (Ki) values of 1,270 +/- 250, 5.0 +/- 0.4, 5.5 +/- 0.3, and 392 +/- 150 nM (n = 3), respectively. In Northern blot analysis we found that MDCK cells expressed transcripts encoding alpha 2A-AR and not alpha 2B-AR or alpha 2C-AR. Surface binding experiments suggested that approximately 60% of alpha 2A-ARs are distributed at the cell surface domain. Specific binding of [3H]MK-912 to soluble apical and basolateral surface proteins isolated by surface biotinylation indicated the expression of surface alpha 2A-ARs was limited to the apical domain of MDCK cells. No alpha 2A-ARs were detected on the basolateral surface. We conclude that endogenous alpha 2A-ARs are targeted to the apical domain of MDCK cells and that the intracellular compartment may contain ARs as a reservoir for de novo cell surface expression or, alternatively, may represent internalized receptors.


This article has been cited by other articles:


Home page
 J. Neurosci.Home page
T. Olli-Lahdesmaki, J. Kallio, and M. Scheinin
Receptor Subtype-Induced Targeting and Subtype-Specific Internalization of Human alpha 2-Adrenoceptors in PC12 Cells
J. Neurosci., November 1, 1999; 19(21): 9281 - 9288.
[Abstract] [Full Text] [PDF]

Home page
 Am. J. Physiol. Cell Physiol.Home page
K. Amsler and S. K. Kuwada
Membrane receptor location defines receptor interaction with signaling proteins in a polarized epithelium
Am J Physiol Cell Physiol, January 1, 1999; 276(1): C91 - C101.
[Abstract] [Full Text] [PDF]

Home page
 Am. J. Physiol. Renal Physiol.Home page
M. D. Okusa, L. Huang, A. Momose-Hotokezaka, L. P. Huynh, and A. J. Mangrum
Regulation of adenylyl cyclase in polarized renal epithelial cells by G protein-coupled receptors
Am J Physiol Renal Physiol, December 1, 1997; 273(6): F883 - F891.
[Abstract] [Full Text] [PDF]


HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
Visit Other APS Journals Online