LUMBAR CSF 5- HYDROXYINDOLEACETIC ACID AND HOMOVANILLIC ACID IN AFFECTIVE SYNDROMES

There seems to be a increase in the absolute level of baseline or probenecid-induced concentrations of these metabolites in older subjects which may be due to an increase in monoamine oxidasc activity with age.

Abstract

Lumbar cercbrospinal fluid (CSF) 5-hydroxyindoleacetic acid (5-HIAA) and homovanillic acid (HVA) have been measured following probenccid administration in psychiatric patients. Values obtained probably reflect composite rates of formation of these acid monoamine metabolites at various sites within the central nervous system. Both absolute values for 5-HIAA and HVA and the 5-HIAA to HVA ratio are helpful in the interpretation of results. There seems to be an increase in the absolute level of baseline or probenecid-induced concentrations of these metabolites in older subjects which may be due to an increase in monoamine oxidasc activity with age.In a group of unipolar depressives (no history of mania) prctreatment values for CSF 5-HIAA were not different from controls while CSF HVA was increased leading to a somewhat decreased 5-HIAA to HVA ratio.Treatment with amitryptyline led to significant reductions in 5-HIAA and the 5-HIAA to HVA ratio.In a group of bipolar patients (history of mania) pretrcatment values for both metabolites were decreased compared to controls. The values for the 5-HIAA to HVA ratio were somewhat elevated.In a group of atypical depressives treated with phenclzinc, CSF 5-HIAA and HVA values were consistent with the presence of central monoamine oxidase inhibition.