Nigral Tau pathology and striatal amyloid-β deposition does not correlate with striatal dopamine deficit in Alzheimer's disease

Extrapyramidal symptoms may appear in Alzheimer's disease (AD). In the present study, using morphometric immunohistochemistry in 34 cases with AD-related pathology, we evaluated whether nigral burden of tau pathology or striatal burden of amyloid-beta deposition correlates with dopamine transporter (DAT) expression in the striatum. Our observations show a lack of correlation between these variables and support the notion that lower striatal DAT expression in AD patients suggests concomitant nigral alpha-synuclein pathology. Extrapyramidal symptoms may have a complex background in AD.