Elevated cerebrospinal fluid SNAP-25 in schizophrenia.
BACKGROUND
Research suggests an association between abnormal exocytosis and schizophrenia. We previously demonstrated increased synaptosomal associated protein, 25 kDa (SNAP-25), a member of the exocytotic mechanism, in the cerebrospinal fluid (CSF) of schizophrenia subjects. In this study, we explored SNAP-25 level and clinical variables in a new group of subjects.


METHODS
Twenty-five haloperidol-treated subjects with chronic schizophrenia and twenty-five healthy control subjects participated in the study. Subjects received haloperidol treatment for at least 3 months and then had a lumbar puncture (n = 19). Medication was replaced by placebo, and the lumbar puncture was repeated (n = 25) after 6 weeks or sooner if limited psychotic symptoms occurred. We measured the level of SNAP-25 in the CSF and symptoms with the Brief Psychiatric Rating Scale (BPRS).


RESULTS
In both haloperidol (p =.001) and placebo (p =.001) treatment conditions, SNAP-25 was elevated. There was no significant difference in SNAP-25 level between conditions. We identified significant positive correlations among SNAP-25 and the BPRS total score and psychosis and thinking disturbance subscales in subjects on haloperidol.


CONCLUSIONS
These observations confirm our previous report of elevated CSF SNAP-25 and suggest that synaptic pathology may be linked with the pathophysiology of schizophrenia.
Thompson
Peter M
PM
Department of Psychiatry, University of Texas Health Science Center at San Antonio, San Antonio, Texas 78229, USA.
Kelley
Mary
M
Yao
Jeffrey
J
Tsai
Guochuan
G
van Kammen
Daniel P
DP
D000328:Adult; D014150:Antipsychotic Agents / Q000008:administration & dosage; D015415:Biomarkers / Q000134:cerebrospinal fluid; D016022:Case-Control Studies; D018492:Dopamine Antagonists / Q000008:administration & dosage; D005089:Exocytosis; D006220:Haloperidol / Q000008:administration & dosage; D006801:Humans; D008565:Membrane Proteins / Q000134:cerebrospinal fluid*; D008875:Middle Aged; D009419:Nerve Tissue Proteins / Q000134:cerebrospinal fluid*; D011569:Psychiatric Status Rating Scales; D012559:Schizophrenia / Q000134:cerebrospinal fluid* / Q000188:drug therapy / Q000503:physiopathology; D013129:Spinal Puncture; D009435:Synaptic Transmission; D050825:Synaptosomal-Associated Protein 25
D014150:Antipsychotic Agents; D015415:Biomarkers; D018492:Dopamine Antagonists; D008565:Membrane Proteins; D009419:Nerve Tissue Proteins; C494208:SNAP25 protein, human; D050825:Synaptosomal-Associated Protein 25; D006220:Haloperidol