Jakary Angela, Vinogradov Sophia, Feiwell Robert, Deicken Raymond F
Psychiatry Service, 116-N, Veterans Affairs Medical Center, 4150 Clement Street, San Francisco, CA 94121, USA.
Schizophr Res. 2005 Jul 15;76(2-3):173-85. doi: 10.1016/j.schres.2005.02.012. Epub 2005 Apr 15.
Deficits in the mediodorsal and anterior nuclei of the thalamus may contribute to the psychopathological symptoms of schizophrenia. These thalamic nuclei have been found to be abnormal in schizophrenia and have close connections with other brain structures implicated in the disorder. We therefore examined schizophrenia-related alterations in brain metabolite levels specifically in the mediodorsal and anterior thalamic subregions.
We used in vivo proton magnetic resonance spectroscopic imaging ((1)H MRSI) to measure N-acetylaspartate (NAA), choline-containing compounds (Cho), and creatine+phosphocreatine (Cr) in the mediodorsal and anterior thalamus in 22 male patients with schizophrenia and 22 male controls. Magnetic resonance imaging (MRI) tissue segmentation and thalamic volume mask techniques were performed to distinguish the thalamus, extrathalamic gray and white matter, and CSF within the spectroscopic voxels.
Compared to healthy subjects, patients with schizophrenia had significantly lower NAA in the mediodorsal and anterior thalamus bilaterally. No significant differences in Cho or Cr levels were seen. NAA was significantly higher in the left thalamus relative to the right in both groups. We found a strong negative correlation between left thalamic NAA and duration of illness, even after partialling out the effect of age. Tissue segmentation and thalamic volume mask techniques detected no group or lateralized differences in tissue type or CSF percentages, demonstrating that the metabolite reductions were not an artifact of spectroscopic voxel heterogeneity.
These findings suggest diminished function and/or structure in the mediodorsal and anterior thalamus in male patients with schizophrenia and support earlier research demonstrating schizophrenia-related abnormalities in the thalamus and its circuitry.
丘脑内侧背核和前核的功能缺陷可能导致精神分裂症的精神病理症状。已发现这些丘脑核在精神分裂症中存在异常，且与该疾病中涉及的其他脑结构有密切联系。因此，我们专门研究了精神分裂症相关的脑代谢物水平变化，特别是在丘脑内侧背核和前核亚区域。
我们使用活体质子磁共振波谱成像（(1)H MRSI）来测量22名男性精神分裂症患者和22名男性对照者丘脑内侧背核和前核中的N-乙酰天门冬氨酸（NAA）、含胆碱化合物（Cho）以及肌酸+磷酸肌酸（Cr）。采用磁共振成像（MRI）组织分割和丘脑体积掩膜技术，以区分波谱体素内的丘脑、丘脑外灰质和白质以及脑脊液。
与健康受试者相比，精神分裂症患者双侧丘脑内侧背核和前核中的NAA显著降低。Cho或Cr水平未见显著差异。两组中左侧丘脑的NAA均显著高于右侧。我们发现即使排除年龄影响后，左侧丘脑NAA与病程之间仍存在强烈的负相关。组织分割和丘脑体积掩膜技术未检测到组织类型或脑脊液百分比的组间或侧化差异，表明代谢物减少并非波谱体素异质性的假象。
这些发现提示男性精神分裂症患者丘脑内侧背核和前核的功能和/或结构受损，并支持早期研究表明丘脑及其神经回路存在与精神分裂症相关的异常。
