Excessive dopamine neuron loss in progressive supranuclear palsy.

ABSTRACT

Progressive supranuclear palsy (PSP) and Parkinson's disease (PD) differ in their response to dopaminergic replacement therapies, despite having a similar degree of neuronal degeneration in the dopaminergic substantia nigra. We observed more widespread dopamine neuron loss in the extranigral A10 midbrain cell groups in PSP compared with PD. These cell groups innervate subcortical and cortical regions and may be required for adequate response to levodopa therapy.