Department of Biophysics, Molecular Biology and Bioinformatics, University of Calcutta, Kolkata, India.
Int J Dev Biol. 2020;64(4-5-6):353-366. doi: 10.1387/ijdb.190130sg.
The zebrafish (Danio rerio), among all amniotes is emerging as a powerful model to study vertebrate organogenesis and regeneration. In contrast to mammals, the adult zebrafish is capable of regenerating damaged axonal tracts; it can replace neurons and glia lost after spinal cord injury (SCI) and functionally recover. In the present paper, we report ultrastructural and cell biological analyses of regeneration processes after SCI. We have focused on event specific analyses of spinal cord regeneration involving different neuronal and glial cell progenitors, such as radial glia, oligodendrocyte progenitors (OPC), and Schwann cells. While comparing the different events, we frequently refer to previous ultrastructural analyses of central nervous system (CNS) injury in higher vertebrates. Our data show (a) the cellular events following injury, such as cell death and proliferation; (b) demyelination and remyelination followed by target innervation and regeneration of synaptic junctions and c) the existence of different progenitors and their roles during regeneration. The present ultrastructural analysis corroborates the cellular basis of regeneration in the zebrafish spinal cord and confirms the presence of both neuronal and different glial progenitors.
斑马鱼（Danio rerio）作为一种强有力的脊椎动物器官发生和再生模型，在所有羊膜动物中逐渐兴起。与哺乳动物不同，成年斑马鱼能够再生受损的轴突束；它可以在脊髓损伤（SCI）后替代丢失的神经元和神经胶质细胞，并恢复功能。在本文中，我们报告了 SCI 后再生过程的超微结构和细胞生物学分析。我们专注于涉及不同神经元和神经胶质细胞祖细胞（如放射状胶质细胞、少突胶质细胞前体细胞（OPC）和施万细胞）的特定于事件的脊髓再生分析。在比较不同事件时，我们经常参考先前对高等脊椎动物中枢神经系统（CNS）损伤的超微结构分析。我们的数据表明：（a）损伤后的细胞事件，如细胞死亡和增殖；（b）脱髓鞘和再髓鞘，随后是靶神经支配和突触连接的再生；以及（c）不同祖细胞的存在及其在再生过程中的作用。目前的超微结构分析证实了斑马鱼脊髓再生的细胞基础，并确认了神经元和不同神经胶质祖细胞的存在。
