Le Roux P D, Reh T A
Department of Neurosurgery, University of Washington, Seattle 98195.
J Neurosci. 1994 Aug;14(8):4639-55. doi: 10.1523/JNEUROSCI.14-08-04639.1994.
To determine whether glia from different CNS regions differ in their ability to support axons or dendrites, embryonic (E18) mouse cortical neurons were cocultured with early postnatal (P4) rat astroglial derived from cortex, retina, olfactory bulb, mesencephalon, striatum, and spinal cord. After 5 d in vitro, axon and dendrite outgrowth from isolated neurons was quantified with double-labeling immunohistochemical techniques. Whereas axonal growth was similar on the various monolayers, total primary dendritic outgrowth was nearly threefold greater on glia derived from the cortex, retina, and olfactory bulb than on glia derived from mesencephalon, striatum, or spinal cord. This effect was principally on the number of primary dendrites rather than the elongation of individual dendrites. Similar morphological differences were observed when cortical neurons were grown on polylysine in a noncontact coculture system with glia continuously conditioning the media. This selective promotion of dendrite growth was independent of neuron survival. These results indicate that there are regional differences in the ability of CNS glia to support dendritic growth and that this effect is due, in part, to release of a diffusable factor.
为了确定来自中枢神经系统（CNS）不同区域的神经胶质细胞在支持轴突或树突方面的能力是否存在差异，将胚胎期（E18）小鼠皮质神经元与出生后早期（P4）源自皮质、视网膜、嗅球、中脑、纹状体和脊髓的大鼠星形胶质细胞进行共培养。体外培养5天后，使用双标记免疫组织化学技术对分离神经元的轴突和树突生长进行定量分析。虽然轴突在各种单层细胞上的生长相似，但源自皮质、视网膜和嗅球的神经胶质细胞上的初级树突总生长量几乎是源自中脑、纹状体或脊髓的神经胶质细胞上的三倍。这种效应主要体现在初级树突的数量上，而非单个树突的伸长。当皮质神经元在聚赖氨酸上生长，并与持续调节培养基的神经胶质细胞处于非接触共培养系统中时，也观察到了类似的形态学差异。这种对树突生长的选择性促进与神经元存活无关。这些结果表明，中枢神经系统神经胶质细胞在支持树突生长的能力上存在区域差异，且这种效应部分归因于一种可扩散因子的释放。
