Abstract

The in vitro pharmacological properties of AR-A000002 (( R)- N-[5-methyl-8-(4-methylpiperazin-1-yl)-1,2,3,4-tetrahydro-2-naphthyl]-4-morpholinobenzamide), a novel 5-hydroxytryptamine (5-HT) 1B receptor antagonist, were studied. AR-A000002 bound with high affinity to guinea pig cortex and recombinant guinea pig 5-HT 1B receptors ( K i=0.24 and 0.47 nM) and with 10-fold lower affinity to 5-HT 1D receptors. The compound displayed weak or no affinity for 63 other binding sites tested. In [ 35S]GTPγS assays AR-A000002 showed 50% efficacy and inhibited 5-HT stimulation with 66% and a p A 2 value of 8.9. In slices of guinea pig cortex, AR-A000002 enhanced the outflow of [ 3H]5-HT upon electrical stimulation. The compound blocked sumatriptan-evoked contraction of rabbit saphenous veins without inducing any contraction itself. Thus, in these two systems AR-A000002 behaved as a 5-HT 1B receptor antagonist. It is concluded that AR-A000002 is a selective high affinity 5HT 1B receptor ligand that shows partial agonist activity in recombinant systems. In native tissues AR-A000002 behaves as a 5-HT 1B receptor antagonist.

Full Text
Paper version not known

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.