Presynaptic and postsynaptic striatal dopaminergic function in neuroacanthocytosis: a positron emission tomographic study.
Using [18F]dopa, [11C]raclopride, C15O2, and positron emission tomography, we have assessed striatal dopamine storage capacity, dopamine D2-receptor integrity, and regional cerebral blood flow, respectively, of 6 patients with neuroacanthocytosis. The patients with neurocanthocytosis all had chorea and variable combinations of seizures, dementia, axonal neuropathy, and orolingual self-multiation. [18F]dopa positron emmission tomographic findings were compared with 30 normal controls and 16 patients with sporadic, L-dopa-responsive, Parkinson's disease. Caudate and anterior putamen [18F]dopa uptake were normal in patients with neuroacanthocytosis, but mean posterior putamen [18F]dopa uptake was reduced to 42% of normal, similar to that in patients with Parkinson's disease. In patients with neuroacanthocytosis, mean equilibrium caudate: cerebellum and putamen: cerebellum [11C]raclopride uptake ratios were reduced to 54% and 62% of normal, compatible with a 65% and 53% loss of caudate and putamen D2-receptor-binding sites, respectively. Striatal and frontal blood flow was also depressed. The severe loss of D2-receptor-bearing striatal neuron, with concomitant loss of dopaminergic projections from the nigra to the posterior putamen, is consistent with both chorea and extrapyramidal rigidity being features of patients with neuroacanthocytosis.
Brooks
D J
DJ
MRC Cyclotron Unit, Hammersmith Hospital, London, England.
Ibanez
V
V
Playford
E D
ED
Sawle
G V
GV
Leigh
P N
PN
Kocen
R S
RS
Harding
A E
AE
Marsden
C D
CD
D000050:Acanthocytes; D000328:Adult; D000368:Aged; D001927:Brain Diseases / Q000000981:diagnostic imaging* / Q000503:physiopathology; D002421:Caudate Nucleus / Q000098:blood supply / Q000000981:diagnostic imaging; D002531:Cerebellum / Q000000981:diagnostic imaging; D002560:Cerebrovascular Circulation; D003342:Corpus Striatum / Q000000981:diagnostic imaging* / Q000503:physiopathology; D005260:Female; D006801:Humans; D007980:Levodopa / Q000493:pharmacokinetics*; D008297:Male; D008875:Middle Aged; D011699:Putamen / Q000000981:diagnostic imaging; D011954:Receptors, Dopamine / Q000032:analysis; D012016:Reference Values; D014055:Tomography, Emission-Computed
D011954:Receptors, Dopamine; D007980:Levodopa