Dopamine transporter change in drug-naive schizophrenia: an imaging study with 99mTc-TRODAT-1.
The aim of this study was to use a specific dopamine transporter (DAT) ligand, 99mTc-TRODAT-1 with single photon emission computed tomography (SPECT) to investigate the densities of DAT in the striatal dopaminergic system in patients with schizophrenia. Striatal DAT uptakes were measured in 12 drug-nai;ve schizophrenic patients and 12 age- and sex-matched healthy volunteers. The psychometric tools included the Standardized Clinical Assessment for Neuropsychiatry (SCAN) and the Positive and Negative Syndrome Scale (PANSS). Semiquantitative analyses using the ratio of uptake in caudate, putamen, and striatum to occipital lobe, and left-right asymmetry were performed. Decreased TRODAT uptake in the right striatum and increased uptake in the left striatum were found in the schizophrenics. However, there is no overall difference in the average striatum uptake. The right-left asymmetry of the caudate and putamen DAT binding seen in the healthy control group disappeared in the schizophrenia group. The decreased right uptake and increased left uptake in the striatum might lead to the lack of right-left asymmetry in neuroleptic-nai;ve schizophrenia patients, confirming that the disorder could be due to a disruption in brain lateralization. This is the first report on the use TRODAT to evaluate the DAT density in schizophrenia patients and shows lack of asymmetry in striatal uptake of TRODAT in schizophrenics. The findings also suggest that TRODAT SPECT may be a useful technique to measure dopamine transmission in the human brain and for understanding the pathophysiology of neuropsychiatric disorders.
Hsiao
Mei-Chun
MC
Department of Psychiatry, Chang Gung Memorial Hospital, Chang Gung University, School of Medicine, Taiwan, ROC.
Lin
Kun-Ju
KJ
Liu
Chia-Yih
CY
Tzen
Kai-Yuan
KY
Yen
Tzu-Chen
TC
D000293:Adolescent; D000328:Adult; D002421:Caudate Nucleus / Q000000981:diagnostic imaging / Q000503:physiopathology; D003342:Corpus Striatum / Q000000981:diagnostic imaging* / Q000503:physiopathology; D004292:Dominance, Cerebral / Q000502:physiology; D050483:Dopamine Plasma Membrane Transport Proteins; D005260:Female; D006801:Humans; D008297:Male; D008562:Membrane Glycoproteins; D026901:Membrane Transport Proteins / Q000378:metabolism*; D008875:Middle Aged; D009419:Nerve Tissue Proteins; D009778:Occipital Lobe / Q000000981:diagnostic imaging / Q000503:physiopathology; D015609:Organotechnetium Compounds; D011699:Putamen / Q000000981:diagnostic imaging / Q000503:physiopathology; D012016:Reference Values; D012559:Schizophrenia / Q000000981:diagnostic imaging* / Q000503:physiopathology; D009435:Synaptic Transmission / Q000502:physiology; D015899:Tomography, Emission-Computed, Single-Photon; D014326:Tropanes
D050483:Dopamine Plasma Membrane Transport Proteins; D008562:Membrane Glycoproteins; D026901:Membrane Transport Proteins; D009419:Nerve Tissue Proteins; D015609:Organotechnetium Compounds; C493214:SLC6A3 protein, human; D014326:Tropanes; C104196:technetium Tc 99m TRODAT-1