title: Attention deficit/hyperactivity disorder: is there a correlation between dopamine transporter density and cerebral blood flow?
abstract: Attention deficit/hyperactivity disorder (ADHD) is one of the most frequent behavioral problems in school-age children. Although the etiology remains unclear, the involvement of the dopaminergic system has been suggested by genetic studies that report an overexpression of the dopamine transporter (DAT) gene. In spite of these abnormalities being directly related to the decrease of dopamine (DA) in the striatum (STR), abnormalities in brain perfusion have also been observed in cortical-subcortical structures. Functional neuroimaging studies have suggested that the DA concentration may cause changes in the cerebral blood flow (CBF). The objective of our study was to evaluate the relationship between DAT density in STR and cortical-subcortical impairment in CBF. Based on the hypothesis that there is a correlation between DA availability and brain perfusion, we postulated that individuals with ADHD, with a higher DAT density in the basal ganglia, will have lower perfusion in the fronto-striatal-cerebellar networks. We used Tc-99m TRODAT-1 SPECT to measure DAT density and Tc-99m ECD SPECT to assess brain perfusion. Ten adolescents diagnosed with ADHD by Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition criteria were investigated. Analysis with Statistical Parametric Mapping 5 corrected for multiple comparisons, using small volume correction, showed a significant negative correlation between the DAT density in the STR and CBF in the cingulate gyrus, frontal lobe, temporal lobe, and cerebellum (pFDR <0.01). Our findings suggest that higher DAT density in the STR was associated with a decrease in the regional CBF in the cortical and subcortical attention network.
authors.affiliation: Laboratório de Medicina Nuclear do Complexo Hospitalar Santa Casa (LAMENU), Porto Alegre, Brazil. neivojr@gmail.com
authors.forename: Neivo
authors.initials: N
authors.lastname: da Silva
authors.forename: Claudia M
authors.initials: CM
authors.lastname: Szobot
authors.forename: Carlos E
authors.initials: CE
authors.lastname: Anselmi
authors.forename: Andrea P
authors.initials: AP
authors.lastname: Jackowski
authors.forename: Shih M
authors.initials: SM
authors.lastname: Chi
authors.forename: Marcelo Q
authors.initials: MQ
authors.lastname: Hoexter
authors.forename: Osvaldo E
authors.initials: OE
authors.lastname: Anselmi
authors.forename: Flavio
authors.initials: F
authors.lastname: Pechansky
authors.forename: Rodrigo A
authors.initials: RA
authors.lastname: Bressan
authors.forename: Luis A
authors.initials: LA
authors.lastname: Rohde
mesh_terms: D000293:Adolescent; D001289:Attention Deficit Disorder with Hyperactivity / Q000000981:diagnostic imaging / Q000378:metabolism* / Q000503:physiopathology*; D001479:Basal Ganglia / Q000098:blood supply / Q000000981:diagnostic imaging / Q000378:metabolism; D002560:Cerebrovascular Circulation; D003545:Cysteine / Q000031:analogs & derivatives; D004298:Dopamine / Q000378:metabolism; D050483:Dopamine Plasma Membrane Transport Proteins / Q000378:metabolism*; D006801:Humans; D008297:Male; D017072:Neostriatum / Q000098:blood supply / Q000000981:diagnostic imaging / Q000378:metabolism; D015609:Organotechnetium Compounds; D015899:Tomography, Emission-Computed, Single-Photon; D014326:Tropanes; D055815:Young Adult
chemical_list: D050483:Dopamine Plasma Membrane Transport Proteins; D015609:Organotechnetium Compounds; D014326:Tropanes; C104196:technetium Tc 99m TRODAT-1; C059659:technetium Tc 99m bicisate; D003545:Cysteine; D004298:Dopamine