title: Adenosine A2 receptors interact negatively with dopamine D1 and D2 receptors in unilaterally 6-hydroxydopamine-lesioned rats.
abstract: In rats bearing a unilateral 6-hydroxydopamine lesion of the dopaminergic nigro-striatal pathway, stimulation of adenosine A2 receptors by CGS 21680 reduced the contralateral turning behavior induced by L-3,4-dihydroxyphenylalanine (L-DOPA). Administration of CGS 21680 completely blocked the contralateral turning induced by the dopamine D1 receptor agonist, SKF 38393, and reduced the turning induced by the dopamine D2 receptor agonist, LY 171555. Quinolinic acid lesion of the striatum or 6-hydroxydopamine lesion of the dopaminergic nigro-striatal neurons demonstrated that [3H]CGS 21680 binding sites are associated to striatal intrinsic neurons. This study provides evidence for a negative postsynaptic interaction of both dopamine D1 and D2 receptors with adenosine A2 receptors.
authors.affiliation: Department of Toxicology, University of Cagliari, Italy.
authors.forename: M
authors.initials: M
authors.lastname: Morelli
authors.forename: S
authors.initials: S
authors.lastname: Fenu
authors.forename: A
authors.initials: A
authors.lastname: Pinna
authors.forename: G
authors.initials: G
authors.lastname: Di Chiara
mesh_terms: D015647:2,3,4,5-Tetrahydro-7,8-dihydroxy-1-phenyl-1H-3-benzazepine / Q000494:pharmacology; D000241:Adenosine / Q000031:analogs & derivatives / Q000378:metabolism; D000818:Animals; D000959:Antihypertensive Agents / Q000378:metabolism; D001345:Autoradiography; D001479:Basal Ganglia / Q000187:drug effects / Q000378:metabolism; D001545:Benserazide / Q000494:pharmacology; D001665:Binding Sites / Q000187:drug effects; D015259:Dopamine Agents / Q000494:pharmacology; D004873:Ergolines / Q000494:pharmacology; D007980:Levodopa / Q000494:pharmacology; D008297:Male; D009434:Neural Pathways / Q000187:drug effects; D009474:Neurons / Q000187:drug effects / Q000378:metabolism; D016627:Oxidopamine / Q000494:pharmacology*; D010627:Phenethylamines / Q000378:metabolism; D017378:Quinolinic Acid / Q000494:pharmacology; D019257:Quinpirole; D051381:Rats; D017207:Rats, Sprague-Dawley; D017447:Receptors, Dopamine D1 / Q000187:drug effects*; D017448:Receptors, Dopamine D2 / Q000187:drug effects*; D018047:Receptors, Purinergic P1 / Q000187:drug effects*; D013239:Stereotyped Behavior / Q000187:drug effects
chemical_list: D000959:Antihypertensive Agents; D015259:Dopamine Agents; D004873:Ergolines; D010627:Phenethylamines; D017447:Receptors, Dopamine D1; D017448:Receptors, Dopamine D2; D018047:Receptors, Purinergic P1; C061282:2-(4-(2-carboxyethyl)phenethylamino)-5'-N-ethylcarboxamidoadenosine; D019257:Quinpirole; D007980:Levodopa; D015647:2,3,4,5-Tetrahydro-7,8-dihydroxy-1-phenyl-1H-3-benzazepine; D001545:Benserazide; D016627:Oxidopamine; D017378:Quinolinic Acid; D000241:Adenosine