Cerebrospinal fluid glutamate inversely correlates with positive symptom severity in unmedicated male schizophrenic/schizoaffective patients.
BACKGROUND
Recent hypotheses have suggested that diminished brain glutamate may be of importance in the neurochemical basis of schizophrenia.


METHODS
We assayed cerebrospinal fluid for glutamate and obtained clinical symptom ratings in 19 medication-free (except p.r.n. chloral hydrate) schizophrenic or schizoaffective (typically with significant schizophrenic qualities) male inpatients.


RESULTS
Ratings of positive symptoms were significantly inversely correlated (rs = -.457, p < .05, one-tailed test) with glutamate concentrations. Hallucinatory behavior was strongly correlated (rs = -.621, p < .01, one-tailed test) with glutamate. A subset of 11 patients consented to a second lumbar puncture (LP) after treatment with haloperidol (typically 15 or 20 mg/day) for 2-4 weeks. Haloperidol treatment did not alter glutamate concentrations. No correlations were noted between glutamate and symptoms in the medicated subsample. Though approximately half the patients received chloral hydrate during the 72 hours prior to the unmedicated LP, the correlations between positive symptoms and glutamate in the patients who received no chloral hydrate prior to the LP were quite similar to those found in the overall sample.


CONCLUSIONS
The results provide further support for the potential importance of glutamate in the neurochemical basis of schizophrenia.
Faustman
W O
WO
Veterans Affairs Health Care System, Psychology Service, VA Palo Alto Health Care System, CA 94304, USA.
Bardgett
M
M
Faull
K F
KF
Pfefferbaum
A
A
Csernansky
J G
JG
D000328:Adult; D014150:Antipsychotic Agents / Q000627:therapeutic use; D018698:Glutamic Acid / Q000134:cerebrospinal fluid*; D006220:Haloperidol / Q000627:therapeutic use; D006801:Humans; D008297:Male; D008875:Middle Aged; D011569:Psychiatric Status Rating Scales; D011618:Psychotic Disorders / Q000134:cerebrospinal fluid* / Q000523:psychology; D012559:Schizophrenia / Q000134:cerebrospinal fluid* / Q000188:drug therapy; D012565:Schizophrenic Psychology
D014150:Antipsychotic Agents; D018698:Glutamic Acid; D006220:Haloperidol