Department of Psychology, Vanderbilt University, 325 Wilson Hall, 111 21st Ave. South, Nashville, TN 37212, USA.
Neuroimage. 2010 May 15;51(1):53-62. doi: 10.1016/j.neuroimage.2010.02.006. Epub 2010 Feb 10.
Individual differences in dopamine D2-like receptor availability arise across all brain regions expressing D2-like receptors. However, the interrelationships in receptor availability across brain regions are poorly understood. To address this issue, we examined the relationship between D2-like binding potential (BPND) across striatal and extrastriatal regions in a sample of healthy participants. PET imaging was performed with the high affinity D2/D3 ligand [18F]fallypride in 45 participants. BPND images were submitted to voxel-wise principal component analysis to determine the pattern of associations across brain regions. Individual differences in D2-like BPND were explained by three distinguishable components. A single component explained almost all of the variance within the striatum, indicating that individual differences in receptor availability vary in a homogenous manner across the caudate, putamen, and ventral striatum. Cortical BPND was only modestly related to striatal BPND and mostly loaded on a distinct component. After controlling for the general level of cortical D2-like BPND, an inverse relationship emerged between receptor availability in the striatum and the ventral temporal and ventromedial frontal cortices, suggesting possible cross-regulation of D2-like receptors in these regions. The analysis additionally revealed evidence of: (1) a distinct component involving the midbrain and limbic areas; (2) a dissociation between BPND in the medial and lateral temporal regions; and (3) a dissociation between BPND in the medial/midline and lateral thalamus. In summary, individual differences in D2-like receptor availability reflect several distinct patterns. This conclusion has significant implications for neuropsychiatric models that posit global or regionally specific relationships between dopaminergic tone and behavior.
个体多巴胺 D2 样受体可用性的差异存在于所有表达 D2 样受体的脑区。然而，脑区之间受体可用性的相互关系尚不清楚。为了解决这个问题，我们在一组健康参与者中研究了纹状体和纹状体外区域 D2 样结合潜能（BPND）之间的关系。在 45 名参与者中进行了高亲和力 D2/D3 配体[18F]氟丙嗪的 PET 成像。BPND 图像被提交给体素-wise 主成分分析，以确定脑区之间的关联模式。D2 样 BPND 的个体差异由三个可区分的成分解释。一个单一的成分解释了几乎所有纹状体内部的方差，表明受体可用性的个体差异在尾状核、壳核和腹侧纹状体中以同质的方式变化。皮质 BPND 与纹状体 BPND 的相关性仅适中，且主要加载在一个独特的成分上。在控制皮质 D2 样 BPND 的一般水平后，纹状体中的受体可用性与腹侧颞叶和腹内侧额叶皮质之间出现了相反的关系，表明这些区域中 D2 样受体可能存在交叉调节。该分析还表明：（1）涉及中脑和边缘区域的独特成分；（2）内侧和外侧颞叶 BPND 的分离；（3）内侧/中线和外侧丘脑 BPND 的分离。总之，D2 样受体可用性的个体差异反映了几种不同的模式。这一结论对神经精神模型具有重要意义，这些模型认为多巴胺能张力和行为之间存在全局或区域性的特定关系。
