Cortical dopamine dysfunction in symptomatic and premanifest Huntington's disease gene carriers.
We used (11)C-raclopride PET, a marker of D(2) dopamine receptor binding, and statistical parametric mapping (SPM) to localise cortical D(2) receptor dysfunction in individual Huntington's disease (HD) gene carriers (16 symptomatic and 11 premanifest subjects) and assess its clinical significance. 62.5% of symptomatic HD patients and 54.5% of premanifest carriers showed cortical reductions in D(2) binding. The most frequent decreases in cortical binding in individual HD subjects were seen in temporal and frontal areas. Symptomatic HD subjects with decreased cortical D(2) binding had worse scores on neuropsychological tests assessing attention and executive functions than subjects without cortical dopamine dysfunction, notwithstanding comparable reduction in striatal D(2) binding and motor disability. Our results indicate that cortical dopaminergic dysfunction is common in both symptomatic and premanifest HD gene carriers. It is an early event in HD pathophysiology and could contribute to the impairment in neuropsychological performance in these patients.
MRC Clinical Sciences Centre and Division of Neuroscience, Faculty of Medicine, Imperial College, Hammersmith Hospital, London, UK. nicola.pavese@csc.mrc.ac.uk
Nicola
N
Pavese
Marios
M
Politis
Yen F
YF
Tai
Roger A
RA
Barker
Sarah J
SJ
Tabrizi
Sarah L
SL
Mason
David J
DJ
Brooks
Paola
P
Piccini
D000328:Adult; D001667:Binding, Competitive / Q000235:genetics; D002250:Carbon Radioisotopes; D002540:Cerebral Cortex / Q000000981:diagnostic imaging / Q000378:metabolism* / Q000503:physiopathology; D004298:Dopamine / Q000378:metabolism*; D018492:Dopamine Antagonists / Q000378:metabolism; D005260:Female; D005625:Frontal Lobe / Q000000981:diagnostic imaging / Q000378:metabolism / Q000503:physiopathology; D005819:Genetic Markers / Q000235:genetics; D006579:Heterozygote; D006801:Humans; D006816:Huntington Disease / Q000235:genetics* / Q000378:metabolism* / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D049268:Positron-Emission Tomography; D011237:Predictive Value of Tests; D011379:Prognosis; D020891:Raclopride / Q000378:metabolism; D017448:Receptors, Dopamine D2 / Q000235:genetics* / Q000378:metabolism*; D013702:Temporal Lobe / Q000000981:diagnostic imaging / Q000378:metabolism / Q000503:physiopathology
D002250:Carbon Radioisotopes; D018492:Dopamine Antagonists; D005819:Genetic Markers; D017448:Receptors, Dopamine D2; D020891:Raclopride; D004298:Dopamine