title: Dopamine D2 and D3 receptors inhibit dopamine release.
abstract: D2-like dopamine receptors are thought to control presynaptic dopamine synthesis and release. Because these receptors comprise a family which includes D2, D3 and D4 dopamine receptors, the question arises as to which subtype performs what role(s). To investigate the potential autoreceptor roles of these proteins, D2, D3 and D4 receptors were transfected into a mesencephalic clonal cell line which synthesizes and releases dopamine. Here we report that stimulation of transfected D2 and D3 receptors, but not D4 receptors, inhibits dopamine release from this dopaminergic cell line. This is the first report of a functional role for D3 receptors and establishes these cell lines as a convenient in vitro model system to study signal transduction mechanisms associated with autoreceptor function.
authors.affiliation: Department of Anatomy and Neurobiology, Washington University School of Medicine, St. Louis, Missouri.
authors.forename: L
authors.initials: L
authors.lastname: Tang
authors.forename: R D
authors.initials: RD
authors.lastname: Todd
authors.forename: K L
authors.initials: KL
authors.lastname: O'Malley
mesh_terms: D015761:4-Aminopyridine / Q000494:pharmacology; D000818:Animals; D002460:Cell Line; D004298:Dopamine / Q000378:metabolism*; D004873:Ergolines / Q000494:pharmacology; D006801:Humans; D008564:Membrane Potentials; D019257:Quinpirole; D051381:Rats; D011954:Receptors, Dopamine / Q000502:physiology*; D017448:Receptors, Dopamine D2 / Q000187:drug effects / Q000502:physiology*; D050637:Receptors, Dopamine D3; D050638:Receptors, Dopamine D4; D011994:Recombinant Proteins; D012457:Salicylamides / Q000494:pharmacology; D019789:Tetraethylammonium; D013757:Tetraethylammonium Compounds / Q000494:pharmacology
chemical_list: C493593:DRD3 protein, human; C493599:DRD4 protein, human; C493595:Drd3 protein, rat; C493601:Drd4 protein, rat; D004873:Ergolines; D011954:Receptors, Dopamine; D017448:Receptors, Dopamine D2; D050637:Receptors, Dopamine D3; D011994:Recombinant Proteins; D012457:Salicylamides; D013757:Tetraethylammonium Compounds; D050638:Receptors, Dopamine D4; D019257:Quinpirole; D019789:Tetraethylammonium; D015761:4-Aminopyridine; C045989:eticlopride; D004298:Dopamine