AB-MECA is an adenosine A3 receptor agonist (Ki = 430.5 nM for the human receptor expressed in CHO cells).1 It inhibits LPS-induced TNF-α production in primary cultured human lung macrophages (pD2 = 6.9).2 AB-MECA increases contraction of isolated guinea pig trachea ex vivo when used at a concentration of 0.1 μM and increases bronchoconstriction in vivo when administered at a dose of 3 μg/kg in a guinea pig model of ovalbumin-sensitized asthma.3 A radiolabeled form of AB-MECA has been used for radioligand binding assays and binds to rat adenosine A1 and A3 receptors (Kds = 3.42 and 1.48 nM in COS-7 and CHO cells, respectively) and canine adenosine A2a receptors (Kd = 25.1 nM in COS-7 cells).4
1.Yates, L., Clark, J.H., Martin, T.J., et al.Radioligand binding and functional responses of ligands for human recombinant adenosine A3 receptorsAuton. Autacoid Pharmacol.26(2)191-200(2006) 2.Buenestado, A., Grassin Delyle, S., Arnould, I., et al.The role of adenosine receptors in regulating production of tumour necrosis factor-α and chemokines by human lung macrophagesBr. J. Pharmacol.159(6)1304-1311(2010) 3.Mikus, E.G., Szeredi, J., Boer, K., et al.Evaluation of SSR161421, a novel orally active adenosine A3 receptor antagonist on pharmacology modelsEur. J. Pharmacol.699(1-3)172-179(2013) 4.Olah, M.E., Gallo-Rodriguez, C., Jacobson, K.A., et al.125I-4-aminobenzyl-5'-N-methylcarboxamidoadenosine, a high affinity radioligand for the rat A3 adenosine receptorMol. Pharmacol.45(5)978-982(1994)