Department of Neurobiology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA.
Laboratory of Systems Neuroscience, NIMH, Bethesda, MD, USA.
Nat Commun. 2018 Sep 3;9(1):3549. doi: 10.1038/s41467-018-05780-7.
The striatum shows general topographic organization and regional differences in behavioral functions. How corticostriatal topography differs across cortical areas and cell types to support these distinct functions is unclear. This study contrasted corticostriatal projections from two layer 5 cell types, intratelencephalic (IT-type) and pyramidal tract (PT-type) neurons, using viral vectors expressing fluorescent reporters in Cre-driver mice. Corticostriatal projections from sensory and motor cortex are somatotopic, with a decreasing topographic specificity as injection sites move from sensory to motor and frontal areas. Topographic organization differs between IT-type and PT-type neurons, including injections in the same site, with IT-type neurons having higher topographic stereotypy than PT-type neurons. Furthermore, IT-type projections from interconnected cortical areas have stronger correlations in corticostriatal targeting than PT-type projections do. As predicted by a longstanding model, corticostriatal projections of interconnected cortical areas form parallel circuits in the basal ganglia.
纹状体显示出一般的地形组织和行为功能的区域差异。皮质纹状体地形如何因皮质区域和细胞类型而异，以支持这些不同的功能尚不清楚。本研究使用在 Cre 驱动小鼠中表达荧光报告基因的病毒载体，对比了来自两个 5 层细胞类型（内脑（IT 型）和锥体束（PT 型）神经元的皮质纹状体投射。来自感觉和运动皮层的皮质纹状体投射具有躯体定位，随着注射部位从感觉区到运动区和额叶区移动，地形特异性逐渐降低。IT 型和 PT 型神经元之间的地形组织不同，包括在同一部位的注射，IT 型神经元的地形刻板性高于 PT 型神经元。此外，来自相互连接的皮层区域的 IT 型投射在皮质纹状体靶向方面的相关性比 PT 型投射更强。正如一个长期存在的模型所预测的那样，相互连接的皮层区域的皮质纹状体投射在基底神经节中形成平行回路。
