Asmus Stephen E, Raghanti Mary Ann, Beyerle Eric R, Fleming-Beattie Julia C, Hawkins Sarah M, McKernan Courtney M, Rauh Nicholas A
Biochemistry and Molecular Biology and Biology Programs, Centre College, Danville, KY 40422, USA.
Department of Anthropology and School of Biomedical Sciences, Kent State University, Kent, OH 44242, USA.
J Chem Neuroanat. 2016 Dec;78:1-9. doi: 10.1016/j.jchemneu.2016.07.007. Epub 2016 Jul 20.
Interneurons of the cerebral cortex play a significant role in cortical information processing and are of clinical interest due to their involvement in neurological disorders. In the human neocortex, three subsets of interneurons can be identified based on the production of the calcium-binding proteins parvalbumin, calretinin or calbindin. A subset of interneurons in the mouse cortex expresses the serotonin 3A receptor (5-HTR). Previous work in humans has also demonstrated the presence of a subgroup of cortical neurons that produces the catecholaminergic enzyme tyrosine hydroxylase (TH). Many TH-producing cells in the rat cortex coexpress calretinin and are adjacent to blood vessels. However, little is known about the phenotype of these TH interneurons in humans. Here we immunohistochemically examined the coexpression of TH with parvalbumin, calretinin, calbindin or 5-HTR in human Brodmann's areas 10 and 24, cortical regions with high densities of TH-containing neurons. Colocalization of TH with these calcium-binding proteins and with 5-HTR was not detected in either area. Cortical TH cells were rarely apposed to blood vessels, denoted by immunolabeling for the gliovascular marker aquaporin-4. Our results suggest that the TH-immunoreactive cells in the human cortex do not overlap with any known neurochemically-defined subsets of interneurons and provide further evidence of differences in the phenotype of these cells across species.
大脑皮质的中间神经元在皮质信息处理中发挥着重要作用，并且由于它们与神经系统疾病有关而具有临床研究价值。在人类新皮质中，可以根据钙结合蛋白小白蛋白、钙视网膜蛋白或钙结合蛋白的产生来识别中间神经元的三个亚群。小鼠皮质中的一个中间神经元亚群表达5-羟色胺3A受体（5-HTR）。先前在人类中的研究也证明了存在一群产生儿茶酚胺能酶酪氨酸羟化酶（TH）的皮质神经元。大鼠皮质中许多产生TH的细胞共表达钙视网膜蛋白，并且与血管相邻。然而，对于人类中这些TH中间神经元的表型知之甚少。在这里，我们通过免疫组织化学方法检测了人类布罗德曼区10和24中TH与小白蛋白、钙视网膜蛋白、钙结合蛋白或5-HTR的共表达情况，这两个皮质区域含有高密度的含TH神经元。在这两个区域均未检测到TH与这些钙结合蛋白以及与5-HTR的共定位。通过对胶质血管标志物水通道蛋白-4进行免疫标记表明，皮质TH细胞很少与血管相邻。我们的结果表明，人类皮质中TH免疫反应性细胞与任何已知的神经化学定义的中间神经元亚群都不重叠，并为这些细胞在不同物种间表型的差异提供了进一步的证据。
