A longitudinal study of cerebrospinal fluid angiotensin-converting enzyme in neuroleptic-treated schizophrenia.

1. The aim of the study was to replicate our earlier finding of elevated cerebrospinal fluid (CSF) angiotensin-converting enzyme (ACE) in neuroleptic-treated schizophrenia and to elucidate the correlations between CSF ACE, neuroleptic treatment, and psychotic symptoms in a longitudinal study. 2. Levels of ACE were measured in CSF and serum from 9 acutely psychotic schizophrenic patients at two separate points of time; within a few days of admission and at follow-up after 3-4 weeks. CSF ACE was also determined from 9 healthy controls. 3. The schizophrenic patients showed non-significantly higher levels of CSF ACE than the controls. Although a significant clinical improvement was observed and the neuroleptic medication was reduced during the follow-up period, there were no significant differences in serum or CSF ACE between the two observation points in the schizophrenia group.