Regeneration of the radial nerve cord in a holothurian: A promising new model system for studying post-traumatic recovery in the adult nervous system
Regeneration of the radial nerve cord in a holothurian: A promising new model system for studying post-traumatic recovery in the adult nervous system
复制标题
DOI：
10.1016/j.tice.2008.03.004
复制
发表时间：
2008-10-01
期刊：
影响因子：
2.6
通讯作者：
Heinzeller, Thomas
中科院分区：
文献类型：
--
作者：
Mashanov, Vladimir S.;Zueva, Olga R.;Heinzeller, Thomas
完全横断后，成年海参 Eupentacta Frauatatrix 的桡神经索 (RNC) 会迅速重新生长并重新连接。伴随这种再生的主要细胞事件的描述来自光学和透射电子显微镜。损伤后不久，发生广泛的神经纤维变性和神经元凋亡。横断产生的绳索间隙首先被结缔组织迅速弥合，随后通过再生神经组织弥合。在伤口的两侧，受损 RNC 的神经外膜和神经下层成分形成独立的管状雏形，其上皮壁主要由去分化的神经胶质细胞组成，能够有丝分裂，但也包含一些神经纤维和偶尔的神经元周核。研究表明，神经胶质细胞在再生中发挥着至关重要的作用，不仅为神经纤维的再生提供支持引导支架，而且还通过产生新的神经元。创伤后神经发生的其他机制可能涉及现有核周体的增殖和/或迁移。前部和后部再生朝彼此生长并最终融合以恢复 RNC 的解剖连续性。神经胶质细胞的再分化和神经细胞在神经组织新形成区域的积累使得完全再生的 RNC 的组织学组织与完整脊髓的组织学组织无法区分。作者认为海参 RNC 提供了一个有价值的实验模型，为探索后口动物神经系统再生的基本机制开辟了新的可能性。 (C) 2008 Elsevier Ltd. 保留所有权利。
After a complete transection, the radial nerve cord (RNC) of the adult sea cucumber Eupentacta fraudatrix quickly regrows and reconnects. The description of the major cellular events that accompany this regeneration is derived from light and transmission electron microscopy. Shortly after lesioning, the extensive nerve fiber degeneration and neuronal apoptosis occur. The gap in the cord created by the transection is rapidly bridged, at first by connective tissue and subsequently by regenerating nerve tissue. On either side of the wound, the ectoneural and hyponeural components of the injured RNC form separate tubular rudiments, whose epithelial walls are composed mostly of dedifferentiated glial cells, capable of mitotic division, but also contain some nerve fibers and occasional neuronal perikarya. It is suggested that the glial cells play a crucial role in regeneration not only by providing the supporting guiding scaffold for regrowing nerve fibers, but also by producing new neurons. Other mechanisms of post-traumatic neurogenesis may involve proliferation and/or migration of existing perikarya. The anterior and posterior regenerates grow towards one another and eventually fuse to restore the anatomical continuity of the RNC. Redifferentiation of gliocytes and accumulation of nerve cells in the newly formed regions of the nervous tissue make histological organization of the fully regenerated RNC indistinguishable from that of the intact cord. The authors suggest that the holothurian RNC provides a valuable experimental model, which opens new possibilities for exploring the fundamental mechanisms underlying regeneration of the nervous system in deuterostomes. (C) 2008 Elsevier Ltd. All rights reserved.