MolPharm xPharm- The Comprehensive Pharmacology Reference

Home Help [Feedback] [For Subscribers] [Archive] [Search] [Contents]
QUICK SEARCH:   [advanced]


     

This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Submit a response
Right arrow Alert me when this article is cited
Right arrow Alert me when eLetters are posted
Right arrow Alert me if a correction is posted
Services
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 Murphree, L. J.
Right arrow Articles by Linden, J.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Murphree, L. J.
Right arrow Articles by Linden, J.

Vol. 61, Issue 2, 455-462, February 2002

Human A2A Adenosine Receptors: High-Affinity Agonist Binding to Receptor-G Protein Complexes Containing Gbeta 4

Lauren J. Murphree, Melissa A. Marshall, Jayson M. Rieger, Timothy L. MacDonald, and Joel Linden

Departments of Pharmacology (L.J.M.), Medicine (M.A.M., J.L.), and Chemistry (J.M.R., T.L.M.), University of Virginia, Charlottesville, Virginia

Agonists bind with higher affinity to G protein-coupled heptahelical receptors than to uncoupled receptors. Recombinant A1 and A3 adenosine receptors couple well to Gi/o, but recombinant human A2A adenosine receptors (hA2AAR) couple poorly to Gs and bind agonists with Ki values in binding assays that are much higher than ED50 values for functional responses such as coronary dilation and inhibition of neutrophil oxidative burst. In this study, we produced hA2AAR-G protein complexes in membranes derived from Sf9 cells quadruply infected with receptors and heterotrimeric G protein subunits. The composition of Gbeta markedly influences coupling such that A2AAR-alpha sbeta 1gamma 2 are 8 ± 2% coupled whereas equivalently expressed A2AAR-alpha sbeta 4gamma 2 are 40 ± 2% coupled. Hence, we were able for the first time to accurately measure high-affinity agonist binding to hA2AAR. The agonist 2-[2-(4-amino-3-[125I]iodophenyl)ethylamino]adenosine binds to coupled and uncoupled hA2AAR with KD values of 0.46 nM and 26 nM, respectively, a difference in affinity of 57-fold. The addition of GTPgamma S converts all receptors to the low-affinity state. A2AAR coupling does not influence binding of antagonists including, 125I-4-(2-[7-amino-2-[2-furyl][1,2,4]triazolo[2,3-a][1,3,5]triazin-5-yl-amino]ethyl)phenol (125I-ZM241385), KD = 0.5 nM. Based on a comparison of high-affinity binding sites, N6-3-iodo-2-chlorobenzyladenosine-5'-N-methyluronamide is only 8-fold A3 selective (A2A Ki, H = 18.3 ± 3.2 nM; A3 Ki, H = 2.4 ± 0.3 nM) and 2-chloro-N6-cyclopentyladenosine is only 33-fold A1 selective (A2A Ki, H = 11.0 ± 1.9; A1 Ki, H = 0.3 ± 0.1). We conclude that recombinant hA2AAR can form a high-affinity receptor-G protein complex with alpha sbeta 4gamma 2 that is useful for determining receptor selectivity.

Copyright © 2002 by The American Society for Pharmacology and Experimental Therapeutics


This article has been cited by other articles:


Home page
 J. Leukoc. Biol.Home page
G. Hasko and P. Pacher
A2A receptors in inflammation and injury: lessons learned from transgenic animals
J. Leukoc. Biol., March 1, 2008; 83(3): 447 - 455.
[Abstract] [Full Text] [PDF]

Home page
 J. Pharmacol. Exp. Ther.Home page
T. C. Wan, Z.-D. Ge, A. Tampo, Y. Mio, M. W. Bienengraeber, W. R. Tracey, G. J. Gross, W.-M. Kwok, and J. A. Auchampach
The A3 Adenosine Receptor Agonist CP-532,903 [N6-(2,5-Dichlorobenzyl)-3'-aminoadenosine-5'-N-methylcarboxamide] Protects against Myocardial Ischemia/Reperfusion Injury via the Sarcolemmal ATP-Sensitive Potassium Channel
J. Pharmacol. Exp. Ther., January 1, 2008; 324(1): 234 - 243.
[Abstract] [Full Text] [PDF]

Home page
 J. Pharmacol. Exp. Ther.Home page
Z.-D. Ge, J. N. Peart, L. M. Kreckler, T. C. Wan, M. A. Jacobson, G. J. Gross, and J. A. Auchampach
Cl-IB-MECA [2-Chloro-N6-(3-iodobenzyl)adenosine-5'-N-methylcarboxamide] Reduces Ischemia/Reperfusion Injury in Mice by Activating the A Adenosine Receptor
J. Pharmacol. Exp. Ther., December 1, 2006; 319(3): 1200 - 1210.
[Abstract] [Full Text] [PDF]

Home page
 Cardiovasc ResHome page
L. Hove-Madsen, C. Prat-Vidal, A. Llach, F. Ciruela, V. Casado, C. Lluis, A. Bayes-Genis, J. Cinca, and R. Franco
Adenosine A2A receptors are expressed in human atrial myocytes and modulate spontaneous sarcoplasmic reticulum calcium release
Cardiovasc Res, November 1, 2006; 72(2): 292 - 302.
[Abstract] [Full Text] [PDF]

Home page
 Circ. Res.Home page
I. Ernens, D. Rouy, E. Velot, Y. Devaux, and D. R. Wagner
Adenosine Inhibits Matrix Metalloproteinase-9 Secretion By Neutrophils: Implication of A2a Receptor and cAMP/PKA/Ca2+ Pathway
Circ. Res., September 15, 2006; 99(6): 590 - 597.
[Abstract] [Full Text] [PDF]

Home page
 J. Pharmacol. Exp. Ther.Home page
L. M. Kreckler, T. C. Wan, Z.-D. Ge, and J. A. Auchampach
Adenosine Inhibits Tumor Necrosis Factor-{alpha} Release from Mouse Peritoneal Macrophages via A2A and A2B but Not the A3 Adenosine Receptor
J. Pharmacol. Exp. Ther., April 1, 2006; 317(1): 172 - 180.
[Abstract] [Full Text] [PDF]

Home page
 J. Immunol.Home page
Y.-J. Day, Y. Li, J. M. Rieger, S. I. Ramos, M. D. Okusa, and J. Linden
A2A Adenosine Receptors on Bone Marrow-Derived Cells Protect Liver from Ischemia-Reperfusion Injury
J. Immunol., April 15, 2005; 174(8): 5040 - 5046.
[Abstract] [Full Text] [PDF]

Home page
 Infect. Immun.Home page
A. Thiele, R. Kronstein, A. Wetzel, A. Gerth, K. Nieber, and S. Hauschildt
Regulation of Adenosine Receptor Subtypes during Cultivation of Human Monocytes: Role of Receptors in Preventing Lipopolysaccharide-Triggered Respiratory Burst
Infect. Immun., March 1, 2004; 72(3): 1349 - 1357.
[Abstract] [Full Text] [PDF]

Home page
 Mol. Pharmacol.Home page
S. Gessi, K. Varani, S. Merighi, E. Cattabriga, A. Avitabile, R. Gavioli, C. Fortini, E. Leung, S. M. Lennan, and P. A. Borea
Expression of A3 Adenosine Receptors in Human Lymphocytes: Up-Regulation in T Cell Activation
Mol. Pharmacol., March 1, 2004; 65(3): 711 - 719.
[Abstract] [Full Text] [PDF]

Home page
 Am. J. Physiol. Gastrointest. Liver Physiol.Home page
Y.-J. Day, M. A. Marshall, L. Huang, M. J. McDuffie, M. D. Okusa, and J. Linden
Protection from ischemic liver injury by activation of A2A adenosine receptors during reperfusion: inhibition of chemokine induction
Am J Physiol Gastrointest Liver Physiol, February 1, 2004; 286(2): G285 - G293.
[Abstract] [Full Text] [PDF]

Home page
 J. Leukoc. Biol.Home page
G. W. Sullivan, D. D. Lee, W. G. Ross, J. A. DiVietro, C. M. Lappas, M. B. Lawrence, and J. Linden
Activation of A2A adenosine receptors inhibits expression of {alpha}4/{beta}1 integrin (very late antigen-4) on stimulated human neutrophils
J. Leukoc. Biol., January 1, 2004; 75(1): 127 - 134.
[Abstract] [Full Text] [PDF]

Home page
 J. Immunol.Home page
N. D. Khoa, M. C. Montesinos, A. J. Williams, M. Kelly, and B. N. Cronstein
Th1 Cytokines Regulate Adenosine Receptors and Their Downstream Signaling Elements in Human Microvascular Endothelial Cells
J. Immunol., October 15, 2003; 171(8): 3991 - 3998.
[Abstract] [Full Text] [PDF]

Home page
 Am. J. Physiol. Heart Circ. Physiol.Home page
J. A. Auchampach, Z.-D. Ge, T. C. Wan, J. Moore, and G. J. Gross
A3 adenosine receptor agonist IB-MECA reduces myocardial ischemia-reperfusion injury in dogs
Am J Physiol Heart Circ Physiol, July 11, 2003; 285(2): H607 - H613.
[Abstract] [Full Text] [PDF]

Home page
 J. Biol. Chem.Home page
S. L. Chinault and K. J. Blumer
The C-terminal Tail Preceding the CAAX Box of a Yeast G Protein {gamma} Subunit Is Dispensable for Receptor-mediated G Protein Activation in Vivo
J. Biol. Chem., May 30, 2003; 278(23): 20638 - 20644.
[Abstract] [Full Text] [PDF]

Home page
 Mol. Pharmacol.Home page
J. Fossetta, J. Jackson, G. Deno, X. Fan, X. K. Du, L. Bober, A. Soude-Bermejo, O. de Bouteiller, C. Caux, C. Lunn, et al.
Pharmacological Analysis of Calcium Responses Mediated by the Human A3 Adenosine Receptor in Monocyte-Derived Dendritic Cells and Recombinant Cells
Mol. Pharmacol., February 1, 2003; 63(2): 342 - 350.
[Abstract] [Full Text] [PDF]


Home Help [Feedback] [For Subscribers] [Archive] [Search] [Contents]
All ASPET Journals Molecular Pharmacology Pharmacological Reviews
Molecular Interventions Drug Metabolism and Disposition

Copyright © 2002 by the American Society for Pharmacology and Experimental Therapeutics