The effects of d-amphetamine on extrastriatal dopamine D2/D3 receptors: a randomized, double-blind, placebo-controlled PET study with [11C]FLB 457 in healthy subjects.
OBJECTIVE
The dopamine D(2)/D(3) receptor ligand [(11)C]FLB 457 and PET enable quantification of low-density extrastriatal D(2)/D(3) receptors, but it is uncertain whether [(11)C]FLB 457 can be used for measuring extrastriatal dopamine release.


METHODS
We studied the effects of d-amphetamine (0.3 mg/kg i.v.) on extrastriatal [(11)C]FLB 457 binding potential (BP(ND)) in a randomized, double-blind, placebo-controlled study including 24 healthy volunteers.


RESULTS
The effects of d-amphetamine on [(11)C]FLB 457 BP(ND) and distribution volume (V(T)) in the frontal cortex were not different from those of placebo. Small decreases in [(11)C]FLB 457 BP(ND) were observed only in the posterior cingulate and hippocampus. The regional changes in [(11)C]FLB 457 BP(ND) did not correlate with d-amphetamine-induced changes in subjective ratings of euphoria.


CONCLUSIONS
This placebo-controlled study showed that d-amphetamine does not induce marked changes in measures of extrastriatal dopamine D(2)/D(3) receptor binding. Our results indicate that [(11)C]FLB 457 PET is not a useful method for measuring extrastriatal dopamine release in humans.
Aalto
Sargo
S
Turku PET Centre, University of Turku, 20014 Turku, Finland.
Hirvonen
Jussi
J
Kaasinen
Valtteri
V
Hagelberg
Nora
N
Kajander
Jaana
J
Någren
Kjell
K
Seppälä
Timo
T
Rinne
Juha O
JO
Scheinin
Harry
H
Hietala
Jarmo
J
D000328:Adult; D001921:Brain / Q000000981:diagnostic imaging* / Q000187:drug effects* / Q000378:metabolism; D002250:Carbon Radioisotopes; D003913:Dextroamphetamine / Q000494:pharmacology*; D004298:Dopamine / Q000378:metabolism; D004311:Double-Blind Method; D005625:Frontal Lobe / Q000000981:diagnostic imaging / Q000187:drug effects / Q000378:metabolism; D006179:Gyrus Cinguli / Q000000981:diagnostic imaging / Q000187:drug effects / Q000378:metabolism; D006624:Hippocampus / Q000000981:diagnostic imaging / Q000187:drug effects / Q000378:metabolism; D006801:Humans; D008297:Male; D049268:Positron-Emission Tomography; D011759:Pyrrolidines; D019275:Radiopharmaceuticals; D017448:Receptors, Dopamine D2 / Q000378:metabolism*; D050637:Receptors, Dopamine D3 / Q000378:metabolism*; D012457:Salicylamides; D055815:Young Adult
D002250:Carbon Radioisotopes; D011759:Pyrrolidines; D019275:Radiopharmaceuticals; D017448:Receptors, Dopamine D2; D050637:Receptors, Dopamine D3; D012457:Salicylamides; C065065:FLB 457; D003913:Dextroamphetamine; D004298:Dopamine