title: (+)-Laburnamine, a natural selective ligand and partial agonist for the α4β2 nicotinic receptor subtype.
abstract: (+)-Laburnamine (1), a rare alkaloid extracted from Laburnum anagyroides seeds (∼4 mg from 1 kg), was shown to bind with high affinity (Ki, 293 nM) to the α4β2 nicotinic receptor subtype, which is, respectively, 126 and 136 times higher than to the α3β4 (Ki 37 μM) and α7 subtypes (Ki 40 μM). When its ability to release [(3)H]-dopamine from striatal slices was tested in a functional assay, compound 1 behaved as a partial agonist with an EC50 of 5.8 μM and an Emax that was 43% that of nicotine. When incubated with nicotine in the same assay, 1 prevented a maximal effect from being reached.
authors: Dipartimento di Farmacia, Università degli Studi di Genova, Viale Benedetto XV, 3, I-16132 Genova, Italy. bruno.tasso@unige.it
authors: Bruno
authors: B
authors: Tasso
authors: Federica
authors: F
authors: Novelli
authors: Fabio
authors: F
authors: Sparatore
authors: Francesca
authors: F
authors: Fasoli
authors: Cecilia
authors: C
authors: Gotti
mesh_terms: D000470:Alkaloids / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D000818:Animals; D001667:Binding, Competitive; D003342:Corpus Striatum / Q000378:metabolism; D004298:Dopamine / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D006801:Humans; D007558:Italy; D008024:Ligands; D017072:Neostriatum / Q000378:metabolism; D009538:Nicotine / Q000378:metabolism; D011725:Pyridines / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D011978:Receptors, Nicotinic / Q000187:drug effects*; D012639:Seeds / Q000737:chemistry; D013237:Stereoisomerism
chemical_list: D000470:Alkaloids; D008024:Ligands; D011725:Pyridines; D011978:Receptors, Nicotinic; C582695:laburnamine; C403531:nicotinic receptor alpha4beta2; D009538:Nicotine; D004298:Dopamine