Glutamate transporter 1-expressing glia in the rat substantia nigra-Morphometric analysis and relationships to synapses.,Glia

当前位置： X-MOL 学术 › Glia › 论文详情

Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)

Glutamate transporter 1-expressing glia in the rat substantia nigra-Morphometric analysis and relationships to synapses.
Glia ( IF 5.4 ) Pub Date : 2020-03-14 , DOI: 10.1002/glia.23823
Jean-Pierre Kessler ₁ , Pascal Salin ₁ , Lydia Kerkerian-Le Goff

Affiliation

Glial cells have a major role in protecting neurons against various forms of stress. Especially, astrocytes mediate the bulk of glutamate clearance in the brain via specific membrane transporters (GLAST and GLT1), thereby preventing the occurrence of excitotoxic events. Although glutamate‐mediated mechanisms are thought to contribute to nigral dopaminergic neuron degeneration in Parkinson's disease, detailed information on the organization of glia in the substantia nigra is still lacking. The present study was performed to provide quantitative information on the organization of astroglia and on the relationships between astrocytes and excitatory synapses in the rat substantia nigra. Using immunolabeling of GLT1 and confocal imaging, we found that the substantia nigra was filled with a dense meshwork of immunoreactive astrocyte processes. Stereological analysis performed on electron microscope images revealed that the density of immunoreactive astrocyte plasma membranes was substantial, close to 1 μm²/μm³, in the substantia nigra neuropil, both in the pars compacta and the pars reticulata. Excitatory synapses had on average two thirds of their perimeters free from glia, a disposition that may favor transmitter spillover. The density of glutamatergic synapses, as quantified on confocal images by the simultaneous detection of bassoon and of vesicular glutamate transporter 1 or 2, was very low (0.01 and 0.025 per μm³ in the reticulata and compacta subdivisions, respectively). Thus the ratio of GLT1‐expressing glial membrane surface to glutamatergic synapses was very high (40–100 μm²), suggesting an efficient regulation of extracellular glutamate concentrations.

中文翻译：

大鼠黑质中表达谷氨酸转运蛋白 1 的神经胶质-形态分析和与突触的关系。

神经胶质细胞在保护神经元免受各种形式的压力方面发挥着重要作用。特别是，星形胶质细胞通过特定的膜转运蛋白（GLAST 和 GLT1）介导大脑中大部分谷氨酸清除，从而防止兴奋性毒性事件的发生。尽管谷氨酸介导的机制被认为是导致帕金森病黑质多巴胺能神经元变性的原因，但仍缺乏有关黑质中神经胶质组织的详细信息。本研究旨在提供有关星形胶质细胞组织以及星形胶质细胞与大鼠黑质兴奋性突触之间关系的定量信息。使用 GLT1 的免疫标记和共聚焦成像，我们发现黑质充满了免疫反应性星形胶质细胞过程的密集网状结构。² /μm ³，在黑质神经纤维网中，在致密部和网状部中。兴奋性突触平均有三分之二的周长没有神经胶质，这种倾向可能有利于发射器溢出。通过同时检测巴松管和囊泡谷氨酸转运蛋白 1 或 2 在共聚焦图像上量化的谷氨酸能突触的密度非常低（网状和致密细分中分别为0.01 和 0.025/μm ³）。因此，表达 GLT1 的神经胶质膜表面与谷氨酸能突触的比率非常高（40-100 μm ²），表明细胞外谷氨酸浓度的有效调节。

更新日期：2020-03-14

点击分享查看原文

点击收藏

阅读更多本刊最新论文本刊介绍/投稿指南11