title: Dopamine receptors in human platelets.
abstract: The expression of dopamine receptors by human platelets was investigated by Western blot analysis and immunocytochemical techniques using antibodies raised against dopamine D1-D5 receptor protein. The influence of dopamine D1-like and D2-like receptor agonists on adrenaline-induced platelet aggregation was also investigated. Western blot analysis revealed that platelet membranes bind anti-dopamine D3 or D5 receptor protein antibodies, but not anti-D1, D2 or D4 receptor protein antibodies. Cytospin centrifuged human platelets exposed to anti-dopamine D3 or D5 receptor protein antibodies developed a specific immune staining, whereas no positive staining was noticeable in platelets exposed to other antibodies tested. Both the D1-like receptor agonist 1-phenyl2,3,4,5-tetrahydro-(1H)-3-benzazepine-7,8-diol hydrochloride (SKF 38393) and the D2-like receptor agonist 7-hydroxy-N,N-di-n-propyl-2-aminotetralin (7-OH-DPAT) dose-dependently inhibited adrenaline-induced platelet aggregation. These effects were decreased respectively by the D-like and D2-like receptor antagonists R(+)-2,3,4,5-tetrahydro-3-methyl-5-phenyl-1H-3-benzazepin-7-ol hydrochloride (SCH 23390) and (-)sulpiride. The above findings indicate that human platelets express dopamine D3 and D5 receptors probably involved in the regulation of platelet function.
authors.affiliation: Dipartimento di Scienze Cardiovascolari e Respiratorie, Università La Sapienza, Rome, Italy.
authors.forename: A
authors.initials: A
authors.lastname: Ricci
authors.forename: E
authors.initials: E
authors.lastname: Bronzetti
authors.forename: F
authors.initials: F
authors.lastname: Mannino
authors.forename: F
authors.initials: F
authors.lastname: Mignini
authors.forename: C
authors.initials: C
authors.lastname: Morosetti
authors.forename: S K
authors.initials: SK
authors.lastname: Tayebati
authors.forename: F
authors.initials: F
authors.lastname: Amenta
mesh_terms: D000328:Adult; D015153:Blotting, Western; D002462:Cell Membrane / Q000187:drug effects; D018491:Dopamine Agonists / Q000494:pharmacology*; D018492:Dopamine Antagonists / Q000494:pharmacology*; D006801:Humans; D010974:Platelet Aggregation / Q000187:drug effects; D011954:Receptors, Dopamine / Q000097:blood / Q000187:drug effects* / Q000276:immunology* / Q000378:metabolism
chemical_list: D018491:Dopamine Agonists; D018492:Dopamine Antagonists; D011954:Receptors, Dopamine