![[Feedback]](/icons/banner/feedbackACT.gif){kind=icon}
![[For Subscribers]](/icons/banner/subscriberACT.gif){kind=icon}
![[Archive]](/icons/banner/archiveACT.gif){kind=icon}
![[Search]](/icons/banner/searchACT.gif){kind=icon}
![[Contents]](/icons/banner/tocACT.gif){kind=icon}
|
|
|
|
|
||
TM Palmer, SM Poucher, KA Jacobson and GL Stiles
Department of Medicine, Duke University Medical Center, Durham, North Carolina 27710, USA.
The A2a adenosine receptor (AR) mediates several important physiological effects of adenosine, including vasodilation and inhibition of platelet aggregation. Until recently, no antagonist radioligand of sufficient selectivity or affinity was available. We describe the synthesis and characterization by radioligand binding of 125I-4-(2-[7-amino-2-2-furyl1,2,4triazolo2,3-a- 1,3,5triazin-5-yl- amino]ethyl)phenol (125I-ZM241385) in membranes from two cell types that express A2a ARs. Membranes from Chinese hamster ovary (CHO) cells expressing a recombinant canine A2a AR bound 125I-ZM241385 with high affinity, and agonist competition experiments with 2-(p-carboxyethyl)- phenylamino-5'-N-carboxamidoadenosine, 5'-N-ethylcarboxamidoadenosine, and (-)-N6[(R)-phenylisopropyl]adenosine revealed a potency order characteristic of an A2a AR binding site. Membranes from bovine striatum, which contain a native A2a AR, also bound 125I-ZM214385 with similarly high affinity and also displayed a pharmacological profile for displacement of radioligand binding that was consistent with that of an A2a AR. Also, under conditions in which 125I-ZM241385 bound with high affinity to a recombinant rat A2a AR expressed in CHO cells, no specific binding was detectable in membranes from CHO cells expressing functional rat A1, A2b, or A3 ARs, indicating that over the range of concentrations used in radioligand binding assays, 125I-ZM214385 is a highly selective antagonist radioligand for study of A2a ARs within a given species.
This article has been cited by other articles:
|
|
 |
|
  D. van der Hoeven, T. C. Wan, and J. A. Auchampach Activation of the A3 Adenosine Receptor Suppresses Superoxide Production and Chemotaxis of Mouse Bone Marrow Neutrophils Mol. Pharmacol., September 1, 2008; 74(3): 685 - 696. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 G. Montandon, R. Kinkead, and A. Bairam Disruption of adenosinergic modulation of ventilation at rest and during hypercapnia by neonatal caffeine in young rats: role of adenosine A1 and A2A receptors Am J Physiol Regulatory Integrative Comp Physiol, April 1, 2007; 292(4): R1621 - R1631. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 R. D. Lasley, G. Kristo, B. J. Keith, and R. M. Mentzer Jr. The A2a/A2b receptor antagonist ZM-241385 blocks the cardioprotective effect of adenosine agonist pretreatment in in vivo rat myocardium Am J Physiol Heart Circ Physiol, January 1, 2007; 292(1): H426 - H431. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 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]
|
|
|
|
|
|
H. Ohata, S. Cao, and R. C. Koehler Contribution of adenosine A2A and A2B receptors and heme oxygenase to AMPA-induced dilation of pial arterioles in rats Am J Physiol Regulatory Integrative Comp Physiol, September 1, 2006; 291(3): R728 - R735. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 W. Hleihel, A. Lafoux, N. Ouaini, A. Divet, and C. Huchet-Cadiou Adenosine affects the release of Ca2+ from the sarcoplasmic reticulum via A2A receptors in ferret skinned cardiac fibres Exp Physiol, July 1, 2006; 91(4): 681 - 691. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
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]
|
|
|
|
|
|
T. Milojevic, V. Reiterer, E. Stefan, V. M. Korkhov, M. M. Dorostkar, E. Ducza, E. Ogris, S. Boehm, M. Freissmuth, and C. Nanoff The Ubiquitin-Specific Protease Usp4 Regulates the Cell Surface Level of the A2a Receptor Mol. Pharmacol., April 1, 2006; 69(4): 1083 - 1094. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
W. A. Sands, A. F. Martin, E. W. Strong, and T. M. Palmer Specific Inhibition of Nuclear Factor-{kappa}B-Dependent Inflammatory Responses by Cell Type-Specific Mechanisms upon A2A Adenosine Receptor Gene Transfer Mol. Pharmacol., November 1, 2004; 66(5): 1147 - 1159. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 P. Puntambekar, J. Van Buren, M. Raisinghani, L. S. Premkumar, and V. Ramkumar Direct Interaction of Adenosine with the TRPV1 Channel Protein J. Neurosci., April 7, 2004; 24(14): 3663 - 3671. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
H. K. Shin, Y. W. Shin, and K. W. Hong Role of adenosine A2B receptors in vasodilation of rat pial artery and cerebral blood flow autoregulation Am J Physiol Heart Circ Physiol, February 1, 2000; 278(2): H339 - H344. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 L. Tang, M. Parker, Q. Fei, and R. Loutzenhiser Afferent arteriolar adenosine A2a receptors are coupled to KATP in in vitro perfused hydronephrotic rat kidney Am J Physiol Renal Physiol, December 1, 1999; 277(6): F926 - F933. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
Z. Nie, Y. Mei, R. L. Malek, A. Marcuzzi, N. H. Lee, and V. Ramkumar A Role of p75 in NGF-Mediated Down-Regulation of the A2A Adenosine Receptors in PC12 Cells Mol. Pharmacol., November 1, 1999; 56(5): 947 - 954. [Abstract] [Full Text]
|
|
|
|
 |
|
 M. E. Olah and M. E. Olah Identification of A2a Adenosine Receptor Domains Involved in Selective Coupling to GS. ANALYSIS OF CHIMERIC A1/A2a ADENOSINE RECEPTORS J. Biol. Chem., January 3, 1997; 272(1): 337 - 344. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 L. Belardinelli, J. C. Shryock, J. Ruble, A. Monopoli, S. Dionisotti, E. Ongini, D. M. Dennis, and S. P. Baker Binding of the Novel Nonxanthine A2A Adenosine Receptor Antagonist [3H]SCH58261 to Coronary Artery Membranes Circ. Res., December 1, 1996; 79(6): 1153 - 1160. [Abstract] [Full Text]
|
|
 |
 |
 |
|
 |
 |
 |
