CSF dopamine beta-hydroxylase in schizophrenia.

Dopamine beta-hydroxylase (DBH), the enzyme that converts dopamine to norepinephrine, was measured in the CSF of 30 schizophrenic patients and 27 normal controls. The CSF DBH activity in the patients was not significantly different from that in controls. Levels of CSF DBH activity in individual patients were highly constant over time and were not influenced by clinical state or neuroleptic treatment. Low levels of DBH in CSF did significantly relate to good social and sexual functioning, good prognosis, less symptoms between hospitalizations, and excellent clinical response to neuroleptic treatment. We speculate from these data that low brain DBH activity may produce a type of vulnerability to psychotic decompensation and thereby influence the clinical course, although it does not cause schizophrenia, in general. Low CSF DBH activity may delineate a "reactive" subgroup from the heterogenous population of patients with diagnoses of schizophrenia.