Bhattacharyya A, Oppenheim R W, Prevette D, Moore B W, Brackenbury R, Ratner N
Department of Anatomy and Cell Biology, University of Cincinnati School of Medicine, Ohio 45267-0521.
J Neurobiol. 1992 Jun;23(4):451-66. doi: 10.1002/neu.480230410.
We used polyclonal antisera recognizing S100, a small acidic protein highly enriched in nervous tissue, to stain sections of embryonic chicken lumbosacral spinal cord and hindlimb. S100 immunoreactivity was detected in developing sensory neurons of the dorsal root ganglia (DRG) and motor neurons of the ventral spinal cord as early as embryonic day (E) 5, and staining persisted through hatching. In contrast, expression of S100 first became apparent in Schwann cells at E13, just before myelination, and was not detected in developing skin or muscle. Since S100 beta was present in motor and sensory neurons and is known to promote neuronal survival and neurite extension in vitro (Winningham-Major, Staecker, Barger, Coats, and Van Eldik, 1989), we tested the ability of S100 to promote neuron survival in an in ovo survival assay. Addition of S100 to chick embryos in ovo during the period of naturally occurring motor neuron cell death resulted in a significant increase in motor neuron survival, but had no effect on the in vivo survival of sensory neurons in the DRG. The findings that S100 is present in spinal motor neurons and that the addition of S100 enhances the survival of these cells in vivo are consistent with the possibility that S100 may act as a naturally occurring neuron survival factor during development.
我们使用识别S100的多克隆抗血清来对鸡胚腰骶部脊髓和后肢切片进行染色，S100是一种在神经组织中高度富集的小酸性蛋白。早在胚胎第5天（E5），就在背根神经节（DRG）的发育中的感觉神经元和脊髓腹侧的运动神经元中检测到了S100免疫反应性，并且这种染色一直持续到孵化。相比之下，S100的表达在E13时才在施万细胞中首次明显出现，就在髓鞘形成之前，并且在发育中的皮肤或肌肉中未检测到。由于S100β存在于运动和感觉神经元中，并且已知在体外可促进神经元存活和神经突延伸（Winningham-Major、Staecker、Barger、Coats和Van Eldik，1989年），我们在一项鸡胚存活试验中测试了S100促进神经元存活的能力。在自然发生运动神经元细胞死亡的时期，向鸡胚卵内添加S100导致运动神经元存活率显著增加，但对DRG中感觉神经元的体内存活率没有影响。S100存在于脊髓运动神经元中以及添加S100可提高这些细胞在体内的存活率这一发现，与S100在发育过程中可能作为一种天然存在的神经元存活因子的可能性是一致的。
