Dopamine transporter immunoreactivity in peripheral blood lymphocytes in multiple system atrophy.

Previous studies showed the reduction of dopamine transporter immunoreactivity (DAT-IR) in peripheral blood lymphocytes (PBL) in Parkinson's disease. Here we report the reduction of DAT-IR in PBL in the extrapyramidal variant of multiple system atrophy. These results suggest the reduction of DAT-IR in PBL in a variety of neurodegenerative disorders, provided the presence of damage of the central dopaminergic systems. The reduction of DAT-IR in PBL in these disorders may represent a compensatory phenomenon aimed at reducing intracellular dopamine influx and, consequently, dopamine-mediated aggravation of oxidative stress in these cells.