[Striatal dopamine D2 receptor in Parkinson disease and its related disorders assessed by C-11 NMSP and PET].

Dopamine D2 receptor binding potential (BP) was measured by C-11 N-methylspiperone (NMSP) and PET in normal healthy volunteers and patients with various neurodegenerative diseases including Parkinson disease (PD), multiple system atrophy (MSA), progressive supranuclear palsy (PSP), corticobasal degeneration (CBD), Huntington disease (HD) and so on. In normal aging process, striatal BP was decreased according to the age. In never-medicated Parkinson disease, BP was slightly elevated, which may reflect denervation hypersensitivity in postsynaptic site. In contrast, BP was reduced in MSA (SND type) and HD. C-11 NMSP and PET is useful in better understanding of pathophysiology and differential diagnosis of Parkinson disease and its related disorders.