ELKH-DE Neuroscience Research Group, Department of Anatomy, Histology and Embryology, University of Debrecen, Debrecen, Hungary.
Department of Neuroanatomy and Molecular Brain Research, Faculty of Medicine, Ruhr-Universitat Bochum, Bochum, Germany.
Sci Rep. 2022 Sep 14;12(1):15428. doi: 10.1038/s41598-022-19746-9.
Here we report the morpho-functional features of a novel type of deep-layer neuron. The neuron was selected from a large pool of intracellularly labelled cells based on the large cell body, numerous spine-free dendrites with an overall interneuron morphology. However, the axon gave off long-range axons up to 2.8 mm from the parent soma in layers 5/6 before entering the white matter. The boutons were uniformly distributed along the axon without forming distinct clusters. Dendritic length, surface area and volume values were at least 3 times larger than any known cortical neuron types with the exception of giant pyramidal cells of layer 5. Electron microscopy of the boutons revealed that they targeted dendritic spines (78%) and less frequently dendritic shafts (22%). Nearly half of the postsynaptic dendrites were immunopositive to GABA. Superimposing the axonal field on the orientation map obtained with optical imaging showed a preponderance of boutons to cross-orientations (38%) and an equal representation of iso- and oblique orientations (31%). The results suggest an integrating role for the layer 6 stellate neuron which projects to a functionally broad range of neurons in the deep cortical layers and to other cortical and/or subcortical regions.
我们在此报告一种新型深层神经元的形态功能特征。该神经元是从大量细胞内标记细胞中选择出来的，其具有大细胞体、大量无棘突的树突，整体形态为中间神经元。然而，其轴突在进入白质之前在第 5/6 层远离母体胞体的地方发出长达 2.8 毫米的长程轴突。轴突上的末梢均匀分布，没有形成明显的簇。树突长度、表面积和体积值至少是除第 5 层大锥体神经元以外的任何已知皮层神经元类型的 3 倍。末梢的电子显微镜显示它们靶向树突棘（78%），较少靶向树突干（22%）。近一半的 postsynaptic 树突对 GABA 呈免疫阳性。将轴突场叠加在光学成像获得的方位图上显示，末梢优先跨越方位（38%），等方位和斜方位的代表数量相等（31%）。结果表明，6 层星状神经元具有整合作用，其投射到深层皮层的广泛功能神经元以及其他皮层和/或皮层下区域。
