Department of Neuroscience and Physiology, State University of New York Upstate Medical University, Syracuse, NY 13210, USA.
Neuroscience. 2012 Aug 30;218:367-84. doi: 10.1016/j.neuroscience.2012.05.055. Epub 2012 May 29.
Perineuronal nets (PNNs) are lattice-like substructures of the neural extracellular matrix that enwrap particular populations of neurons throughout the central nervous system. Previous work suggests that this structure plays a major role in modulating developmental neural plasticity and brain maturation. Understanding the precise role of these structures has been hampered by incomplete comprehension of their molecular composition and cellular contributions to their formation, which is studied herein using primary cortical cell cultures. By defining culture conditions to reduce (cytosine-β-d-arabinofuranoside/AraC addition) or virtually eliminate (elevated potassium chloride (KCl) and AraC application) glia, PNN components impacted by this cell type were identified. Effects of depolarizing KCl concentrations alone were also assessed. Our work identified aggrecan as the primary neuronal component of the PNN and its expression was dramatically up-regulated by both depolarization and glial cell inhibition and additionally, the development of aggrecan-positive PNNs was accelerated. Surprisingly, most of the other PNN components tested were made in a glial-dependent manner in our culture system. Interestingly, in the absence of these glial-derived components, an aggrecan- and hyaluronan-reactive PNN developed, demonstrating that these two components are sufficient for base PNN assembly. Other components were expressed in a glial-dependent manner. Overall, this work provides deeper insight into the complex interplay between neurons and glia in the formation of the PNN and improves our understanding of the molecular composition of these structures.
周围神经毡（PNNs）是神经细胞外基质的晶格状亚结构，包裹着中枢神经系统中特定的神经元群体。先前的工作表明，这种结构在调节发育中的神经可塑性和大脑成熟方面起着重要作用。由于对其分子组成和细胞对其形成的贡献不完全理解，因此理解这些结构的确切作用受到了阻碍，本文使用原代皮质细胞培养物对此进行了研究。通过定义培养条件来减少（胞嘧啶-β-d-阿拉伯呋喃糖苷/AraC 添加）或几乎消除（升高的氯化钾 (KCl) 和 AraC 应用）神经胶质细胞，鉴定了受这种细胞类型影响的 PNN 成分。还评估了单独去极化 KCl 浓度的影响。我们的工作确定聚集蛋白聚糖是 PNN 的主要神经元成分，其表达被去极化和神经胶质细胞抑制显著上调，此外，聚集蛋白聚糖阳性 PNN 的发育也得到了加速。令人惊讶的是，在我们的培养系统中，大多数其他测试的 PNN 成分都是以依赖胶质细胞的方式产生的。有趣的是，在没有这些胶质细胞衍生成分的情况下，形成了聚集蛋白聚糖和透明质酸反应性的 PNN，表明这两种成分足以进行基本的 PNN 组装。其他成分以依赖胶质细胞的方式表达。总体而言，这项工作深入了解了神经元和神经胶质细胞在 PNN 形成中的复杂相互作用，并提高了我们对这些结构的分子组成的理解。
