PET measures of amphetamine-induced dopamine release in ventral versus dorsal striatum.
Regional differences in dextroamphetamine (AMPH)-induced dopamine (DA) release in the baboon striatum were assessed using positron emission tomographic (PET) measures of [11C]raclopride specific binding to DA D2/D3 receptors acquired before and after AMPH administration. The magnitude of the reduction in [11C]raclopride binding, following AMPH administration, was two-fold greater in the anteroventral striatum (comprised of ventral caudate, anteroventral putamen, and nucleus accumbens) than the dorsal striatum (dorsal caudate). A simulation study demonstrated that any potential biases due to resolution (partial volume) and alignment effects were significantly smaller than the magnitude of the observed results. These regional differences in the sensitivity of AMPH are compatible with microdialysis evidence in rats indicating that the magnitude of DA release in response to AMPH concentrations in the range tested is greater in ventral than dorsal striatal regions. Post hoc tests involving measures in other striatal regions showed that the baseline DA D2/D3 binding was highest and the correlation between AMPH dose and change in [11C]raclopride binding most significant in the putamen.
Drevets
W C
WC
Department of Psychiatry, University of Pittsburgh School of Medicine, PA 15213, USA.
Price
J C
JC
Kupfer
D J
DJ
Kinahan
P E
PE
Lopresti
B
B
Holt
D
D
Mathis
C
C
D000661:Amphetamine / Q000494:pharmacology*; D000818:Animals; D002250:Carbon Radioisotopes / Q000493:pharmacokinetics; D002421:Caudate Nucleus / Q000378:metabolism; D003342:Corpus Striatum / Q000000981:diagnostic imaging / Q000187:drug effects / Q000378:metabolism*; D004298:Dopamine / Q000378:metabolism*; D005260:Female; D008279:Magnetic Resonance Imaging; D008297:Male; D009714:Nucleus Accumbens / Q000378:metabolism; D010215:Papio; D011699:Putamen / Q000378:metabolism; D020891:Raclopride / Q000493:pharmacokinetics*; D051381:Rats; D017447:Receptors, Dopamine D1 / Q000378:metabolism; D017448:Receptors, Dopamine D2 / Q000378:metabolism; D050637:Receptors, Dopamine D3; D014055:Tomography, Emission-Computed
D002250:Carbon Radioisotopes; C493595:Drd3 protein, rat; D017447:Receptors, Dopamine D1; D017448:Receptors, Dopamine D2; D050637:Receptors, Dopamine D3; D020891:Raclopride; D000661:Amphetamine; D004298:Dopamine