Summary
A grease-gap extracellular recording technique was used to detect 5-HT1A receptor-mediated hyper-polarizing responses to 5-hydroxytryptamine (5-HT) in the rat isolated superior cervical ganglion. In the presence of the novel 5-HT1A receptor antagonist, WAY 100135 [N-tert-butyl-3-(4-(2-methoxyphenyl)piperazin-1-yl)-2-phenylpropanamide], the responses to 5-HT were antagonised in a competitive manner with a pA2 value of 7.2 (6.9–8.5) and Schild plot slope of 1.0 (0.4–1.6), n = 20. The antagonist activity was greater in the (+) than the (−)enantiomer of WAY-100135. The pA2 value of the (+)enantiomer was 7.5 (7.2–8.0), Schild plot slope 1.2 (0.8–1.6), n = 17. In contrast the (−)enantiomer had weak antagonist activity (pA2 6.3±0.25, n = 3). No agonist activity of WAY-100135 or its enantiomers were observed in this study.
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Correspondence to K. F. Rhodes at the above address
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Rhodes, K.F., Dover, G. & Lattimer, N. The antagonist actions of WAY 100135 and its enantiomers on 5-HT1A receptor-mediated hyperpolarization of the rat isolated superior cervical ganglion. Naunyn-Schmiedeberg's Arch Pharmacol 348, 225–227 (1993). https://doi.org/10.1007/BF00169148
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DOI: https://doi.org/10.1007/BF00169148