Phenylethylamine and monoamine metabolites in CSF of schizophrenics: effects of neuroleptic treatment.

Phenylethylamine (PEA) and the monoamine metabolites 3-methoxy-4-hydroxyphenylglycol (MHPG), homovanillic acid (HVA) and 5-hydroxyindoleacetic acid (5-HIAA) have been measured in the cerebrospinal fluid (CSF) of nine paranoid schizophrenics before and after three weeks of neuroleptic treatment. Patients were classified according to the Research Diagnostic Criteria and rated by means of the Brief Psychiatric Rating Scale. A significant increase was seen in HVA CSF concentrations during neuroleptic treatment (p less than 0.01). No influence was found on levels of PEA, 5-HIAA, and MHPG. Concentrations of both MHPG and 5-HIAA correlated positively with those of HVA. These results in combination with previous findings do not support the contention that PEA and NA metabolisms are grossly disturbed in paranoid schizophrenics whereas involvement of other neurotransmitters i.e. dopamine, seems more probable.