[Glutamate increase in the associative striatum in schizophrenia: a longitudinal magnetic resonance spectroscopy preliminary study].
OBJECTIVE
To compare glutamate levels (Glu) found in the dorsal-caudate nucleus (a dopamine rich region) and in the cerebellum (a low dopamine region) among: 1) schizophrenia patients undergoing an acute psychotic episode, 2) after receiving antidopaminergic treatment (Risperidone), and 3) healthy controls.


METHODS
Fourteen drug-free patients with schizophrenia and fourteen healthy controls were included. Patients underwent two proton magnetic resonance spectroscopy (1H-MRS) studies, one prior to treatment and the second after 6-weeks of daily Risperidone treatment. Controls underwent one 1H-MRS study. Glutamate levels were normalized according to the relative concentration of Creatine (Cr).


RESULTS
The dorsal-caudate nucleus among schizophrenia patients showed higher levels of Glu/Cr during the drug-free condition (t = -2.16, p = 0.03) and after antipsychotic treatment (t = 2.12, p = 0.04) compared with controls. No difference was observed in the cerebellum between the drug-free, post-treatment and controls conditions.


CONCLUSIONS
Our results suggest that the Glu increase observed in the dorsal-caudate in schizophrenia is illness-mediated and does not change after 6-weeks of antipsychotic treatment. Moreover, the lack of change detected in the cerebellum suggests that the Glu increase in schizophrenia is not ubiquitous within the brain and that may be associated with dopamine target regions.
de la Fuente-Sandoval
Camilo
C
Laboratorio de Psiquiatría Experimental, Instituto Nacional de Neurología y Neurocirugía Manuel Velasco Suárez, México D.F., México.
Favila
Rafael
R
Alvarado
Patricia
P
León-Ortiz
Pablo
P
Díaz-Galvis
Leonardo
L
Amezcua
Carmen
C
García-Muñoz
Erik
E
Graff-Guerrero
Ariel
A
D000328:Adult; D002421:Caudate Nucleus / Q000737:chemistry*; D002531:Cerebellum / Q000737:chemistry*; D005260:Female; D018698:Glutamic Acid / Q000032:analysis*; D006801:Humans; D008137:Longitudinal Studies; D009682:Magnetic Resonance Spectroscopy; D008297:Male; D012559:Schizophrenia / Q000378:metabolism*; D055815:Young Adult
D018698:Glutamic Acid