Department of Otolaryngology-HNS, Wayne State University School of Medicine , Detroit, MI , USA.
Department of Otolaryngology-HNS, Wayne State University School of Medicine , Detroit, MI , USA ; Department of Otolaryngology, Jinshan Hospital, Fudan University , Shanghai , China.
Front Pediatr. 2013 Dec 17;1:43. doi: 10.3389/fped.2013.00043. eCollection 2013.
In the nerve roots of vertebrates, the peripheral nervous system (PNS) and central nervous system (CNS) interface at the PNS-CNS transitional zone (PCTZ), which consists of cell boundaries with various myelin components. We have recently shown that the mouse cochlear nerve presents an exceptionally long segment of the CNS tissue extending into the PNS using light microscopy. However, it is unclear how oligodendrocytes and Schwann cells contribute to the formation of myelin components of the PCTZ. It is undetermined how myelination is initiated along the cochlear nerve, and when it adopts a mature pattern. In this study, immunofluorescence using antibodies specific to oligodendrocyte marker myelin oligodendrocyte glycoprotein (MOG) and Schwann cell marker myelin protein zero (MPZ) were used to detail the expression of myelin components along the postnatal mouse cochlear nerve. We found that the expression of MPZ was initially observed in the soma of bipolar spiral ganglion neurons at postnatal day 0 (P0) and progressed to the central and peripheral processes after P8-P10. Myelination of the CNS tissue was initiated in close proximity to the PCTZ from P7 to P8 and then extended centrally. Myelination of the PCTZ reached a mature style at P14, when the interface of the expression of MOG and MPZ was clearly identified along the cochlear nerve. This knowledge of PCTZ formation of the cochlear nerve will be essential to future myelination research, and it will also gain clinical interest because of its relevance to the degeneration and regeneration of the auditory pathway in hearing impairment.
在脊椎动物的神经根中，外周神经系统 (PNS) 和中枢神经系统 (CNS) 在周围神经系统-中枢神经系统过渡区 (PCTZ) 相互连接，该区域由具有各种髓鞘成分的细胞边界组成。我们最近发现，使用光学显微镜，小鼠耳蜗神经呈现出一段特别长的 CNS 组织延伸到 PNS 的区域。然而，尚不清楚少突胶质细胞和施万细胞如何有助于形成 PCTZ 的髓鞘成分。尚不清楚髓鞘是如何沿着耳蜗神经起始的，以及它何时采用成熟模式。在这项研究中，使用针对少突胶质细胞标志物髓鞘少突胶质细胞糖蛋白 (MOG) 和施万细胞标志物髓鞘蛋白零 (MPZ) 的抗体进行免疫荧光，以详细描述出生后小鼠耳蜗神经上髓鞘成分的表达。我们发现，MPZ 的表达最初在出生后第 0 天 (P0) 的双极螺旋神经节神经元体中观察到，并在 P8-P10 后进展到中央和外周过程。CNS 组织的髓鞘化从 P7 到 P8 开始在 PCTZ 附近启动，然后向中央延伸。P14 时，PCTZ 的髓鞘化达到成熟形式，此时在耳蜗神经上可以清楚地识别 MOG 和 MPZ 表达的界面。对耳蜗神经 PCTZ 形成的这种了解对于未来的髓鞘化研究至关重要，并且由于其与听力障碍中听觉通路的退化和再生的相关性，它也将引起临床关注。
