HIGHER CEREBROSPINAL-FLUID ANGIOTENSIN-CONVERTING ENZYME LEVELS IN NEUROLEPTIC-TREATED THAN IN DRUG-FREE PATIENTS WITH SCHIZOPHRENIA

The aim of this study was to replicate our earlier finding of elevated angiotensin-converting enzyme (ACE) in cerebrospinal fluid (CSF) in s chizophrenia and to elucidate the role of neuroleptic treatment in thi s phenomenon. Drug-free and medicated patients with acute schizophreni c psychoses, as well as healthy controls were recruited, Levels of ACE were measured in CSF and serum from 7 drug-free patients, 36 neurolep tic-treated patients, and 19 healthy control subjects. Although ACE le vels in CSF did not differ between patients and controls, the drug-fre e patients showed significantly lower levels than the neuroleptic-trea ted patients. Serum ACE did not differ between groups. The elevation o f CSF ACE may be more prominent in patients with deficit symptoms than in those with mainly psychotic symptoms. The possible enhancement of CSF ACE production or solubility by neuroleptic treatment is discussed . Elevated ACE levels in CSF may, together with other possible factors , cause polydipsia, stimulate secretion of arginine vasopressin, and e ven affect neuron growth and differentiation in schizophrenic psychose s.