Qian J A, Bull M S, Levitt P
Department of Anatomy and Neurobiology, Medical College of Pennsylvania, Philadelphia 19129.
Dev Biol. 1992 Feb;149(2):278-94. doi: 10.1016/0012-1606(92)90284-n.
The potential neuroanatomical specificity of astrocyte influence on neurite outgrowth was studied using an in vitro coculture system in which neurons from embryonic rat spinal cord or hippocampus were grown for 4 days in the presence of, but not in direct contact with, astrocytes derived either from the same region (homotopic coculture) or from different regions (heterotopic coculture) of the rat central nervous system. The results showed that axonal outgrowth was greatly enhanced in heterotopic cocultures in which spinal cord or hippocampal neurons were grown with astrocytes derived from their appropriate CNS target regions. This effect was remarkably specific, because the astroglia harvested from spinal or hippocampal target regions were not effective in promoting axon growth of nonafferent neuronal populations. Dendritic outgrowth was similar under all coculture conditions. These data suggest that diffusible signals, produced by astrocytes, can regulate neurite extension in vitro in a neuroanatomically specific manner and that axons are more sensitive than dendrites to the regional astrocyte environment.
利用体外共培养系统研究了星形胶质细胞对神经突生长影响的潜在神经解剖学特异性。在该系统中，来自胚胎大鼠脊髓或海马体的神经元在存在但不直接接触源自大鼠中枢神经系统相同区域（同位共培养）或不同区域（异位共培养）的星形胶质细胞的情况下生长4天。结果表明，在异位共培养中，脊髓或海马神经元与源自其相应中枢神经系统靶区域的星形胶质细胞一起生长时，轴突生长大大增强。这种效应非常具有特异性，因为从脊髓或海马靶区域收获的星形胶质细胞对促进非传入神经元群体的轴突生长无效。在所有共培养条件下，树突生长相似。这些数据表明，星形胶质细胞产生的可扩散信号可以在体外以神经解剖学特异性方式调节神经突延伸，并且轴突比树突对区域星形胶质细胞环境更敏感。
