On the occurrence of homovanillic acid and 5- hydroxyindol- 3- ylacetic acid in the ven-tricular cerebro- spinal fluid of patients suffering from Parkinsonism

We have some evidence that the concentrations of HVA and 5 -H1AA in the C.S.F. of the lateral ventricles may reflect the brain metabolism of the parent cerebral amines, dopamine and 5- hydroxytryptamine. There appears to be a definite rblationship between the concentrations of HVA in the lateral ventricular C.S.F. and the caudate nucleus of dogs and man. (Guldberg, 1967). An approach based on this knowledge has been used in the analysis of ventricular C.S.F. samples of patients undergoing the ste re otaxic operation for the relief of Parkinsonism. The concentrations of HVA and 5 -H1AA were determined in the ventricular C.S.F. of Parkinsonian patients and a control group. There was a significant difference in the mean levels of both metabolites in the 2 groups of patients. The lower levels of the acid metabolites found in the group of Parkinsonian patients has been discussed in the light of our knowledge on the biochemistry of Parkinsonism. We have suggested that the biochemical findings could be explained on the basis of the neuropathological destructions occurring in the disease process and that they are not necessarily indicative of a primary.error of the amine metabolism. Within the group of Parkinsonian patients, lower acid levels were recorded in the group of patients with symptoms of more than 10 years and also in the small number of post -encephalitic patients. In Parkinsonism there was no clear evidence of any association between the mean levels of the metabolites and the following factors: age, sex, presence or absence of drug treatment and the degree of the clinical symptoms of tremor, rigidity or akinesia. The lack of correlation between clinical symptomatology and the acid levels is particularly interesting and we have discussed in some detail the most apparent reasons for this. It is hoped that further work might clarify some of the problems