Trousse F, Giess M C, Soula C, Ghandour S, Duprat A M, Cochard P
Centre de Biologie du Développement, CNRS UMR 9925, affiliée à l'INSERM, Université Paul Sabatier, Toulouse, France.
J Neurosci Res. 1995 Jul 1;41(4):552-60. doi: 10.1002/jnr.490410415.
The regionalization of oligodendrocyte potentialities and the cellular interactions leading to the expression of the oligodendrocyte phenotype have been analyzed in the embryonic chick spinal cord. Dorsal and ventral regions of the spinal cord of 4-day-old embryos (E4) were cultivated separately. Oligodendrocyte differentiation was monitored at various times after explantation, using specific oligodendrocyte markers. After 2 weeks, several hundreds of differentiated oligodendrocytes were invariably observed in ventral cultures whereas significant numbers of oligodendrocytes failed to develop in dorsal spinal cord cultures. However, the E7 dorsal spinal cord was found to produce large numbers of oligodendrocytes, indicating that the ventral restriction of oligodendrocyte potentialities is transient. To test whether ventrally derived signals might influence oligodendrocyte differentiation, E4 dorsal spinal cord microexplants were cocultivated with notochord segments or with floor plate tissue. Numerous oligodendrocytes were found in dorsal explants associated with either tissue, notochord or floor plate, but not in dorsal explants cultivated alone, indicating that cells competent to be induced along the oligodendrocyte phenotype exist in the dorsal spinal cord. These results show that oligodendrocyte differentiation potentialities are initially restricted to the ventral spinal cord and suggest that ventrally derived signals from notochord and floor plate influence oligodendrocyte differentiation in the embryonic spinal cord.
在胚胎期鸡的脊髓中，已对少突胶质细胞潜能的区域化以及导致少突胶质细胞表型表达的细胞间相互作用进行了分析。将4日龄胚胎（E4）脊髓的背侧和腹侧区域分别进行培养。在接种后的不同时间，使用特异性少突胶质细胞标记物监测少突胶质细胞的分化情况。2周后，在腹侧培养物中总是能观察到数百个分化的少突胶质细胞，而在背侧脊髓培养物中，大量少突胶质细胞未能发育。然而，发现E7背侧脊髓能产生大量少突胶质细胞，这表明少突胶质细胞潜能的腹侧限制是短暂的。为了测试腹侧来源的信号是否可能影响少突胶质细胞的分化，将E4背侧脊髓微型外植体与脊索节段或底板组织共同培养。在与脊索或底板这两种组织相关的背侧外植体中发现了大量少突胶质细胞，但在单独培养的背侧外植体中未发现，这表明背侧脊髓中存在有能力被诱导形成少突胶质细胞表型的细胞。这些结果表明，少突胶质细胞的分化潜能最初局限于脊髓腹侧，并提示来自脊索和底板的腹侧来源信号影响胚胎脊髓中少突胶质细胞的分化。
