中文摘要：

目的：初步探讨背侧抑制性轴突导向蛋白即draxin对鸡胚后脑23C10阳性神经元轴突投射过程中的调控作用。方法：对HH13-14发育阶段的正常鸡胚后脑内进行跨膜型和分泌型draxin质粒转染,通过免疫组织化学染色方法,观察HH25-26发育阶段鸡胚23C10阳性神经元轴突的投射情况;应用活组织离体培养方法,检测draxin对鸡胚后脑神经元轴突生长的影响。结果：跨膜型draxin过表达后,有较多23C10阳性神经元的轴突异常投射到同侧后脑背侧部;分泌型draxin过表达后,有少部分23C10阳性神经元的轴突异常投射到同侧后脑背侧部;正常鸡胚和空白质粒过表达对照组均未观察到异常投射的神经元轴突。鸡胚后脑活组织离体培养中,draxin显著抑制体外培养组织内树突的生长,而对照组可见体外培养的组织内有大量树突形成。结论：draxin对鸡胚后脑内23C10阳性神经元的轴突投射具有抑制性导向作用。

英文摘要：

Objective： To investigate the role of the repulsive axon guidance protein,draxin,in the development of23C10 positive neuronal axons in the chick hindbrain. Methods： Immunohistochemistry at HH25-26 chick hindbrain was used to observe the development of 23C10 positive neuronal axon followed by the trans-membrane and secreted draxin plasmid overexpression at the stage of HH13-14. The function of draxin on the chicken embryo hindbrain neuronal axon growth was detected by in vitro culture method. Results： After the overexpression of the trans-membrane form of draxin,23C10-positive axons were misprojected in the dorsal roof of the electroporated side of the hindbrain region. After the overexpression of secreted draxin,there were a few misprojected 23C10-positive axons in the dorsal roof of the electroporated side of the hindbrain region. There were no apparent 23C10-positive axons in the dorsal roof of the hindbrain region after the overexpression of the control vector and the normal group. Inhibition of neurite outgrowth was found in the explants cultured by draxin conditioned medium,compared with the explants cultured in control conditioned medium.Conclusion： Draxin has an inhibitory guiding effect on the projection of 23C10-positive neuronal axons in the chicken embryos hindbrain.