정신분열증 환자의 전두엽에서 양성자 자기공명 분광법에 의한 치료전 • 후의 대사물질 변화

Alteration of Proton Metabolites of the Frontal Lobe Before and After Treatment in Schizophrenics by Proton Magnetic Resonance Spectroscopy

Objects : It has been reported that some schizophrenics have structural abnormalities of the prefrontal lobe by magnetic resonance imaging. Magnetic resonance spectroscopy(MRS) provides noninvasive in vivo assessment of brain tissue composition and metabolic processes. Thus, using localized, water suppressed in vivo rH MRS it has become ]possible to monitor a number of proton metabolites including putative neurotransmitter amino acids that may be implicated in the pathogenesis of schizophrenia. In this study we used MRS to investigate the proton metabolites differences o f the both prefrontal cortex between schizophrenics and normal controls, and to examine if there would be a difference of proton metabolites before and after treatment in schizophrenics. Methods : The subjects consisted of 24 hospitalized patients who fulfilled criteria for chronic schizophrenia by DSM-IV. All subjects were further interviewed to rate the severity of clinical symptoms on Brief Psychiatric Rating Scale(BPRS), and Positive and Negative Syndrome Scale (PANSS). The follow-up evaluations were performed eight to twelve weeks after treatment for 19 patients whose BPRS scores moderately decreased. All were examined with localized in vivo lH M R spectroscopy in both prefronal lobes to measure proton metabolites and their change possibly associated with treatment. Results ： The results were as follows ； 1) The spcctral features of some distinct proton metabolites such as N-acetyl aspartate(NAA), inositol, creatine / phosphocreatine(Cr)，choline-containing compounds, glutamate(Glu), gamma aminobutyric acid(GABA) were clearly identified in both schizophrenics and healthy controls. 2) The schizophrenics had significantly higher ratios of(GABA+ Glu)/ C r compared to contxols( ANOVAR, F=18.63, P=0.0001). However, a significant decrease in N A A /C r ratio was found in schizophrenics(ANOVAR, F=9.05, P=0.005). 3) There were no significant differences in proton metabolites between the right and the left in the schizophrenic group and control group. 4) The comparsion of ratios before and after treatment showed that(GABA+Glu)/ Cr ratio was significantly decreased after treatment(ANOVAR, F=10.34, P=0.027). However, there were no significant differences in ratios of other proton metabolites. 5) Norelationships were noted between proton metabolites and psychopathology on either BPRS and PANSS Concusions ： In light of our results, it seems likely that the decrease of NAA / Cr ratio which would be closely associated with neuronal damage supports the hypofrontality hypothesis, and clinical symptoms would be related to the change of GABA or glutamate.