Brain Catecholamines and Their Metabolites in Parkinsonian Patients

Abstract
Analyses of autopsy samples of parkinsonian patients showed significantly decreased concentrations of dopamine and homovanillic acid (HVA) in extrapyramidal brain regions. Twelve patients treated with levodopa alone or combined with a decarboxylase inhibitor showed concentrations of dopamine and HVA which ranged from values corresponding to nontreated parkinsonian patients to levels above those in controls. Increase of concentration of HVA was relatively more marked than that of dopamine. There were no significant changes in the concentration of noradrenaline. Histological examination of brain samples showed no changes related to the treatment.