title: Binding of pramipexole to extrastriatal dopamine D2/D3 receptors in the human brain: a positron emission tomography study using 11C-FLB 457.
abstract: The purpose of this study was to determine the binding sites of pramipexole in extrastriatal dopaminergic regions because its antidepressive effects have been speculated to occur by activating the dopamine D(2) receptor subfamily in extrastriatal areas. Dynamic positron emission tomography (PET) scanning using (11)C-FLB 457 for quantification of D(2)/D(3) receptor subtype was performed on 15 healthy volunteers. Each subject underwent two PET scans before and after receiving a single dose of pramipexole (0, 0.125, or 0.25 mg). The study demonstrated that pramipexole significantly binds to D(2)/D(3) receptors in the prefrontal cortex, amygdala, and medial and lateral thalamus at a dose of 0.25 mg. These regions have been indicated to have some relation to depression and may be part of the target sites where pramipexole exerts its antidepressive effects.
authors.affiliation: Positron Medical Center, Tokyo Metropolitan Institute of Gerontology, Tokyo, Japan. jkoprich@uhnres.utoronto.ca
authors.forename: Kenji
authors.initials: K
authors.lastname: Ishibashi
authors.forename: Kenji
authors.initials: K
authors.lastname: Ishii
authors.forename: Keiichi
authors.initials: K
authors.lastname: Oda
authors.forename: Hidehiro
authors.initials: H
authors.lastname: Mizusawa
authors.forename: Kiichi
authors.initials: K
authors.lastname: Ishiwata
mesh_terms: D000328:Adult; D000368:Aged; D052160:Benzothiazoles / Q000378:metabolism* / Q000493:pharmacokinetics; D002250:Carbon Radioisotopes; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D017072:Neostriatum / Q000000981:diagnostic imaging* / Q000378:metabolism; D049268:Positron-Emission Tomography; D000077487:Pramipexole; D011759:Pyrrolidines; D017448:Receptors, Dopamine D2 / Q000378:metabolism*; D050637:Receptors, Dopamine D3 / Q000378:metabolism*; D012457:Salicylamides; D013997:Time Factors
chemical_list: D052160:Benzothiazoles; D002250:Carbon Radioisotopes; D011759:Pyrrolidines; D017448:Receptors, Dopamine D2; D050637:Receptors, Dopamine D3; D012457:Salicylamides; C065065:FLB 457; D000077487:Pramipexole