In vitro pharmacological characterization of a novel unbiased NOP receptor-selective nonpeptide agonist AT-403.pdf (2.5 MB)
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In vitro pharmacological characterization of a novel unbiased NOP receptor-selective nonpeptide agonist AT-403.

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journal contribution
posted on 25.04.2018, 11:32 by F. Ferrari, D. Malfacini, B. V. Journigan, Mark F. Bird, C. Trapella, R. Guerrini, David G. Lambert, G. Calo', N. T. Zaveri
Nociceptin/orphanin FQ (N/OFQ) regulates several biological functions via selective activation of the N/OFQ receptor (NOP), a member of the opioid receptor family. We recently identified a new high affinity and highly selective NOP agonist AT-403. In this study, we characterized the functional profile of AT-403 and compared it to other known nonpeptide NOP agonists Ro 65-6570, Ro 2q, SCH-221510, MCOPPB, AT-202 and SCH-486757, using the following assays: GTPγ[35S] stimulated binding, calcium mobilization assay in cells-expressing human NOP or classical opioid receptors and chimeric G proteins, bioluminescence resonance energy transfer (BRET) based assay for studying NOP receptor interaction with G protein and arrestin, and the electrically stimulated mouse vas deferens bioassay. All compounds behaved as NOP full agonists consistently showing the following rank order of potency MCOPPB > AT-403 > Ro 65-6570 = Ro 2q > SCH-221510 >  AT-202 > SCH-486757. AT-403 and MCOPPB displayed the highest NOP selectivity both at human and murine receptors. Interestingly, while all the other nonpeptide NOP agonists displayed bias toward G protein-mediated signaling in the BRET assay, AT-403, similar to the natural ligand N/OFQ, behaved as an unbiased agonist, activating G-protein-mediated function as well as arrestin recruitment. AT-403 may be a useful nonpeptide tool compound to study the pharmacology of NOP activation in disease states.



Pharmacology Research and Perspectives, 2017, 5 (4), e00333

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/Organisation/COLLEGE OF LIFE SCIENCES/School of Medicine/Department of Cardiovascular Sciences


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