John Nora, Krügel Hans, Frischknecht Renato, Smalla Karl-Heinz, Schultz Christian, Kreutz Michael R, Gundelfinger Eckart D, Seidenbecher Constanze I
Department for Neurochemistry and Molecular Biology, Leibniz Institute for Neurobiology Magdeburg, Germany.
Mol Cell Neurosci. 2006 Apr;31(4):774-84. doi: 10.1016/j.mcn.2006.01.011. Epub 2006 Feb 28.
Perineuronal nets (PNN) are specialized extracellular matrix structures enwrapping CNS neurons, which are important regulators for neuronal and synaptic functions. Brevican, a chondroitin sulfate proteoglycan, is an integral component of PNN. Here, we have investigated the appearance of these structures in hippocampal primary cultures. The expression profile of brevican in mixed cultures resembles the in vivo pattern with a strong upregulation of all isoforms during the second and 3rd weeks in culture. Brevican is primarily synthesized by co-cultured glial fibrillary acidic protein (GFAP-)-positive astrocytes and co-assembles with its interaction partners in PNN-like structures on neuronal somata and neurites as identified by counterstaining with the PNN marker Vicia villosa lectin. Both excitatory and inhibitory synapses are embedded into PNN. Furthermore, axon initial segments are strongly covered by a dense brevican coat. Altogether, we show that mature primary cultures can form PNN, and that basic features of these extracellular matrix structures may be studied in vitro.
神经周网（PNN）是包裹中枢神经系统神经元的特殊细胞外基质结构，是神经元和突触功能的重要调节因子。短蛋白聚糖是一种硫酸软骨素蛋白聚糖，是神经周网的一个组成部分。在此，我们研究了这些结构在海马原代培养物中的出现情况。短蛋白聚糖在混合培养物中的表达谱类似于体内模式，在培养的第二和第三周所有异构体均有强烈上调。短蛋白聚糖主要由共培养的胶质纤维酸性蛋白（GFAP）阳性星形胶质细胞合成，并与其相互作用伙伴在神经元胞体和神经突上的类神经周网结构中共同组装，这通过用神经周网标记物野豌豆凝集素进行复染得以鉴定。兴奋性和抑制性突触均嵌入神经周网。此外，轴突起始段被致密的短蛋白聚糖包被强烈覆盖。总之，我们表明成熟的原代培养物可以形成神经周网，并且这些细胞外基质结构的基本特征可以在体外进行研究。
