CEREBROSPINAL-FLUID HOMOVANILLIC-ACID IS REDUCED IN UNTREATED HUNTINGTONS-DISEASE

We measured homovanillic acid (HVA), 5-hydroxy indole acetic acid (5-H 1AA), and tryptophan (TP) in cerebrospinal fluid (CSF) of 20 neurolept ic-free patients with Huntington's disease (HD), and compared mean val ues with those from four control groups including 15 normal individual s, 38 patients with dystonia, 23 untreated patients with Parkinson's d isease, and 61 patients with other neurological diseases (ONDs). The m ean levels of HVA in the CSF of patients with HD were reduced compared with those from normal controls (p < 0.001), dystonic patients (p < 0 .005), individuals with ONDs (p < 0.0001), and even from untreated par kinsonian patients (p < 0.05). 5-HIAA and TP levels in the CSF of pati ents with HD were not significantly different from those in the CSF of control patients. Our data suggest a reduced dopamine neurotransmissi on in HD and may account for the bradykinesia observed in our patients .