Imaging of serotonin and dopamine transporters in the living human brain.
Alterations in brain serotonin (5-HT) and dopamine (DA) activity are associated with several neuropsychiatric disorders, but until now it has not been possible to simultaneously visualize or quantify the 5-HT and the DA transporter density in the living human brain. In this paper we report on the imaging of 5-HT and DA transporters in 28 healthy controls with single-photon emission tomography using iodine-123 labelled 2 beta-carbomethoxy-3 beta-(4-iodophenyl)tropane ([123I] beta-CIT) as the tracer. The [123I] beta-CIT distribution showed the most prominent 5-HT activity in the medial frontal cortex, hypothalamus, midbrain and occipital cortex and the greatest DA activity in the basal ganglia. The specific binding of the 5-HT transporters in the medial frontal cortex was 0.377 +/- 0.031 and that of the DA transporters in the basal ganglia, 0.916 +/- 0.007. Gjedde-Patlak plots indicated two separate components: the first was assumed to represent 5-HT transporters with a slope of 1.29 +/- 0.27 h-1 and the second, DA transporters with a slope of 0.30 +/- 0.04 h-1. This distinct kinetic pattern and the fact that 5-HT and DA transporters are situated in different parts of the brain provides an opportunity to study in vivo patients suffering from various neuropsychiatric disorders.
Kuikka
J T
JT
Department of Clinical Physiology, Kuopio University Hospital, Finland.
Tiihonen
J
J
Bergström
K A
KA
Karhu
J
J
Hartikainen
P
P
Viinamäki
H
H
Länsimies
E
E
Lehtonen
J
J
Hakola
P
P
D000328:Adult; D001921:Brain / Q000000981:diagnostic imaging*; D001923:Brain Chemistry; D002352:Carrier Proteins / Q000032:analysis*; D003042:Cocaine / Q000031:analogs & derivatives*; D003866:Depressive Disorder / Q000000981:diagnostic imaging; D004298:Dopamine / Q000032:analysis*; D050483:Dopamine Plasma Membrane Transport Proteins; D005260:Female; D006801:Humans; D007457:Iodine Radioisotopes; D008297:Male; D008562:Membrane Glycoproteins / Q000032:analysis*; D026901:Membrane Transport Proteins; D008875:Middle Aged; D009419:Nerve Tissue Proteins; D016584:Panic Disorder / Q000000981:diagnostic imaging; D010300:Parkinson Disease / Q000000981:diagnostic imaging; D012559:Schizophrenia / Q000000981:diagnostic imaging; D012701:Serotonin / Q000032:analysis*; D050486:Serotonin Plasma Membrane Transport Proteins; D015899:Tomography, Emission-Computed, Single-Photon
D002352:Carrier Proteins; D050483:Dopamine Plasma Membrane Transport Proteins; D007457:Iodine Radioisotopes; D008562:Membrane Glycoproteins; D026901:Membrane Transport Proteins; D009419:Nerve Tissue Proteins; C493230:SLC6A4 protein, human; D050486:Serotonin Plasma Membrane Transport Proteins; D012701:Serotonin; C069723:2beta-carbomethoxy-3beta-(4-iodophenyl)tropane; D003042:Cocaine; D004298:Dopamine