Serotonergic mechanism in Parkinsonism

Cerebrospinal fluid 5-hydroxyindole acetic acid (CSF 5-HIAA), platelet serotonin (5-hydroxytryptamine, 5-HT) uptake and basal platelet 5-HT were evaluated in patients of Parkinson's disease (PD). Platelet 5-HT uptake and content and CSF 5-HIAA were reduced, which suggests a deficient central serotonergic activity in PD. Reduced platelet 5-HT uptake and content may also indicate deficient peripheral serotonergic activity.