title: High-affinity antagonists of the locust neuronal octopamine receptor.
abstract: The pharmacological antagonistic properties of the invertebrate specific octopamine receptor were investigated using a conventional radio-receptor assay with [3H]octopamine as the radioligand. Among the antagonists with highest affinity of the locust (Locusta migratoria L.) neuronal octopamine receptor were tetracyclic substances like mianserin (K1 = 1.2 nM), some of its derivatives (8-hydroxymianserin; K1 = 1.68 nM), and maroxepine, which is the antagonist with the highest affinity ever reported (K1 = 1.02 nM) to this octopamine receptor class. Among the other antagonists tested only phentolamine (K1 = 19 nM) and promethazine (K1 = 31.2 nM) had high-affinity properties.
authors.affiliation: Universität Hamburg, Zoologisches Institut, F.R.G.
authors.forename: T
authors.initials: T
authors.lastname: Roeder
mesh_terms: D000818:Animals; D003984:Dibenzazepines / Q000378:metabolism*; D005260:Female; D005724:Ganglia / Q000378:metabolism; D006110:Grasshoppers; D008297:Male; D008803:Mianserin / Q000031:analogs & derivatives* / Q000378:metabolism*; D009417:Nerve Tissue / Q000378:metabolism; D011869:Radioligand Assay; D011941:Receptors, Adrenergic / Q000378:metabolism*; D017982:Receptors, Biogenic Amine
chemical_list: D003984:Dibenzazepines; D011941:Receptors, Adrenergic; D017982:Receptors, Biogenic Amine; C027604:norsynephrine receptor; D008803:Mianserin; C029337:8-hydroxymianserin; C068397:maroxepin