The effect of risperidone on metabolite measures in the frontal lobe, temporal lobe, and thalamus in schizophrenic patients. A proton magnetic resonance spectroscopy (1H MRS).

Department of Psychiatry, Medical University in Bialystok, Bialystok, Poland.
Pharmacopsychiatry (Impact Factor: 2.17). 10/2005; 38(5):214-9. DOI: 10.1055/s-2005-873156
Source: PubMed

ABSTRACT The aim of the study was the evaluation of risperidone effect on metabolite measures in the frontal lobe, temporal lobe and thalamus in schizophrenic patients on the basis of proton magnetic resonance spectroscopy ( (1)H MRS).
A group of 14 patients with the diagnosis of schizophrenia, according to DSM-IV, were examined in the study. The patients were examined twice, once after a period of at least 7 days without neuroleptics and for the second time at least 4 weeks after stable risperidone doses.
The significant differences in the metabolite levels before and after the treatment were observed only in thalamus: an increase in myoinositol (mI) and N-acetylaspartate (NAA) levels. Positive symptoms before the treatment correlated positively with NAA level in the frontal lobes and negatively in the temporal lobes. Negative symptoms before the treatment correlated positively with Glx (a common signal for GABA, glutamine and glutamate) level in the temporal lobes.
Our results seem to confirm the influence of risperidone on the brain metabolism, specifically in the region of thalamus.

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