Visualizing vesicular dopamine dynamics in Parkinson's disease

Abstract

It has been suggested that dopamine derived from exogenous levodopa may not follow vesicular dynamics in Parkinson's disease (PD). Using a novel PET method based on the sensitivity of [(11)C]-dihydrotetrabenazine (DTBZ) binding to changes in vesicular dopamine levels, we show here that striatal [(11)C]-DTBZ binding decreases after levodopa administration in advanced PD, likely reflecting an increase in vesicular dopamine levels. Endogenous dopamine and exogenously derived dopamine seem to follow the same vesicular dynamics.