Striatal dopamine D2 receptors, metabolism, and volume in preclinical Huntington disease

Department of Neurology, Groningen University Medical Center, Groningen, The Netherlands.
Neurology (Impact Factor: 8.3). 09/2005; 65(6):941-3. DOI: 10.1212/
Source: PubMed

ABSTRACT Among 27 preclinical carriers of the Huntington disease mutation (PMC), the authors found normal striatal values for MRI volumetry in 88% and for fluorodesoxyglucose PET metabolic index in 67%. Raclopride PET binding potential (RAC-BP) was decreased in 50% and correlated with increases in the product of age and CAG repeat length (p < 0.0005). Dopamine D2 receptor availability measured by RAC-BP seems the most sensitive indicator of early neuronal impairment in PMC.

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