Psychiatry Investig.  2013 Mar;10(1):75-80.

Is the GABA System Related to the Social Competence Improvement Effect of Aripiprazole? An 18F-Fluoroflumazenil PET Study

• Lee JS
• Lee JD
• Park HJ
• Oh MK
• Chun JW
• Kim SJ
• Kim E
• Kim JJ

Abstract

OBJECTIVE
Patients with schizophrenia who are treated with aripiprazole experience some benefits including an improvement of social competence, but the underlying mechanism of this improvement has not been investigated yet. This study aimed to provide preliminary evidence that the GABA system may be involved in the effect of aripiprazole on social competence.
METHODS
Seventeen outpatients with schizophrenia (9 taking aripiprazole and 8 taking risperidone) and 18 healthy controls underwent 18F-fluoroflumazenil PET, and GABAA receptor binding potential was compared between the three groups.
RESULTS
Voxelwise one-way ANOVA showed that GABAA receptor binding potentials in the right medial prefrontal cortex (p=0.04) and right dorsolateral prefrontal cortex (p=0.02) were significantly lower in the aripiprazole group than the risperidone group, and those in the left frontopolar cortex (p=0.03) and right premotor cortex (p=0.02) were significantly lower in the aripiprazole group than the risperidone and control groups.
CONCLUSION
Our results suggest that aripiprazole administration results in increased GABA transmission in the prefrontal regions, and that these increases may be a neural basis of aripiprazole's clinical benefits on an improvement of social competence.

Keyword

GABAA receptor; Flumazenil PET; Aripiprazole; Social competence; Prefrontal cortex

MeSH Terms

gamma-Aminobutyric Acid
Humans
Mental Competency
Outpatients
Piperazines
Prefrontal Cortex
Quinolones
Risperidone
Schizophrenia
Aripiprazole
Piperazines
Quinolones
Risperidone
gamma-Aminobutyric Acid