In vivo detection of microglial activation in frontotemporal dementia

MRC Cyclotron Unit, MRC Clinical Sciences Centre, Imperial College London, Hammersmith Hospital Campus, London, United Kingdom.
Annals of Neurology (Impact Factor: 11.91). 12/2004; 56(6):894-7. DOI: 10.1002/ana.20332
Source: PubMed

ABSTRACT Using positron emission tomography and [(11)C](R)-PK11195, a marker of "peripheral benzodiazepine sites" that is upregulated on activated microglia during progressive tissue pathology, we show increased binding of [(11)C](R)-PK11195 in frontotemporal lobar degeneration in the typically affected frontotemporal brain regions. This implies the presence of an active glial response reflecting progressive neuronal degeneration. It also suggests that increased [(11)C](R)-PK11195 binding, previously demonstrated for Alzheimer's disease, may occur independently from increased amyloid plaque formation, given that it is not a characteristic feature of frontotemporal lobar degeneration.

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Mar 23, 2015