AXONAL TRAJECTORIES AND DISTRIBUTION OF GABAERGIC SPINAL NEURONS IN WILDTYPE AND MUTANT ZEBRAFISH LACKING FLOOR PLATE CELLS
AXONAL TRAJECTORIES AND DISTRIBUTION OF GABAERGIC SPINAL NEURONS IN WILDTYPE AND MUTANT ZEBRAFISH LACKING FLOOR PLATE CELLS
复制标题
DOI：
10.1002/cne.903260208
复制
发表时间：
1992-12-08
影响因子：
2.5
通讯作者：
KUWADA, JY
中科院分区：
文献类型：
--
作者：
BERNHARDT, RR;PATEL, CK;KUWADA, JY
通过比较野生型斑马鱼胚胎和cyc-1突变胚胎中假定的GABA能神经元，研究了中线底板细胞在脊髓神经元分化中的作用。突变产生一个多效性隐性致死表型，是严重的吻侧脑区，但其直接影响在尾侧后脑和脊髓显然是有限的中线底板细胞的耗尽。在野生型胚胎中，针对神经递质GABA的抗体标记了三类先前鉴定的神经元的细胞体、轴突和生长锥;背纵神经元（DoLA）。连合次级上行神经元（CoSA）和腹侧纵行神经元（VeLD）。一种新的腹侧细胞类型，Kolmer-Agduhr（KA）神经元，也被标记。在cyc-1突变体中，观察到GABA反应性CoSA、VeLD和KA轴突的一些（但不是全部）异常，而DoLA神经元的轴突轨迹不受影响。此外，KA细胞的数量在突变体中减少，而其他GABA反应性细胞的数量未受干扰。这些观察结果证实了我们先前的假设，即底板细胞是脊髓腹侧中线附近轴突生长的几个指导线索之一。他们还表明底板细胞可能在斑马鱼胚胎脊髓的细胞分化中起作用。
The role of the midline floor plate cells in the neuronal differentiation of the spinal cord was examined by comparing putative GABAergic neurons in wildtype zebrafish embryos with those in cyc-1 mutant embryos. The mutation produces a pleiotropic recessive lethal phenotype and is severe in rostral brain regions, but its direct effect in the caudal hindbrain and the spinal cord is apparently restricted to the depletion of the midline floor plate cells. In wildtype embryos, an antibody against the neurotransmitter GABA labeled the cell bodies, axons, and growth cones of three classes of previously identified neurons; dorsal longitudinal neurons (DoLA). commissural secondary ascending neurons (CoSA), and ventral longitudinal neurons (VeLD). A novel ventral cell type, Kolmer-Agduhr (KA) neurons, was also labeled. In the cyc-1 mutant, abnormalities were observed in some, but not all, of the GABAreactive CoSA, VeLD, and KA axons, while the axonal trajectories of DoLA neurons were not affected. Furthermore, the number of KA cells was reduced in the mutant while the numbers of the other GABAreactive cells were unperturbed. These observations corroborate our earlier hypothesis that the floor plate cells are one of several guidance cues that direct axonal outgrowth near the ventral midline of the spinal cord. They also suggest that the floor plate cells may play a role in the cellular differentiation of the spinal cord of zebrafish embryos.