The effect of olanzapine treatment on m-chlorophenylpiperazine-induced hormone release in schizophrenia.
J Clin Psychopharmacol
; 21(6): 575-82, 2001 Dec.
Article
in En
| MEDLINE
| ID: mdl-11763004
ABSTRACT
In addition to dopamine, serotonin (5-hydroxytryptamine, 5-HT) has been reported to play an important role in schizophrenia. Besides blocking dopamine, atypical antipsychotics also block 5-HT receptors. The clinical efficacy of the atypical antipsychotic clozapine is associated with the 5-HT antagonistic action of the drug and a high serotonergic tone before treatment. The atypical antipsychotic olanzapine has a receptor-binding profile similar to that of clozapine. The present study investigated whether treatment with olanzapine blocks hormone release induced by the 5-HT2c agonist m-chlorophenylpiperazine (m-CPP) and, if so, whether this 5-HT antagonistic effect is related to treatment response. Eighteen male schizophrenic patients participated in this study. All patients were challenged with m-CPP (0.5 mg/kg orally) in a double-blind, randomized, placebo-controlled design after a drug-free period of at least 2 weeks. Adrenocorticotropic hormone (ACTH), cortisol, and prolactin plasma levels were measured every 30 minutes up to 210 minutes after challenge. Patients were treated for 6 weeks with 10 mg olanzapine daily in an open design, after which the challenge tests were repeated. Olanzapine significantly blocked m-CPP-induced ACTH, cortisol, and prolactin release, suggesting that it is a potent 5-HT2c antagonist in vivo. This 5-HT antagonistic effect of olanzapine was not significantly correlated with treatment response. Also, no significant correlation was found between m-CPP-induced hormone release before treatment and clinical response after treatment with olanzapine. These findings suggest that olanzapine is a potent 5-HT2c antagonist in vivo but that this is unrelated to its clinical efficacy in this nonrefractory sample of schizophrenic patients.
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Collection:
01-internacional
Database:
MEDLINE
Main subject:
Piperazines
/
Schizophrenia
/
Pirenzepine
/
Selective Serotonin Reuptake Inhibitors
/
Serotonin Receptor Agonists
/
Hormones
Type of study:
Clinical_trials
/
Prognostic_studies
Limits:
Adult
/
Humans
/
Male
Language:
En
Journal:
J Clin Psychopharmacol
Year:
2001
Document type:
Article
Affiliation country:
Netherlands
Country of publication:
EEUU
/
ESTADOS UNIDOS
/
ESTADOS UNIDOS DA AMERICA
/
EUA
/
UNITED STATES
/
UNITED STATES OF AMERICA
/
US
/
USA