增强声环境中嗅球神经前体细胞在耳蜗核的迁移

Migration of neural precursor cells derived from olfactory bulb in cochlear nucleus exposed to an augmented acoustic environment

目的观察增强声环境中移植到大鼠耳蜗核的嗅球神经前体细胞的迁移特点,是否产生部位特异性的修复过程。方法培养嗅球神经前体细胞取自孕14-16d胚胎大鼠,荧光染色Hoechst33342标记后移植到成年大鼠的耳蜗核内侧缘。移植大鼠分为A、B两组,A组置于增强声环境,B组在正常环境中饲养。14d取材观察移植细胞的迁移和分化。结果A组移植细胞有沿听觉神经通路移动的趋势。免疫荧光技术观察到Hoechst33342和神经元核蛋白(NeuN)、谷氨酸阳性三重标记的移植细胞。结论嗅球神经前体细胞移植耳蜗核短期存活良好,增强声刺激可能促进前体细胞在听觉系统的迁移。

Objective Acoustic signals may induce a site-specific cell replacement in the auditory system. This hypothesis was tested with grafted implantation of neural precursor cells （NPCs） along the cochlear nucleus in the adult rat followed by an augmented acoustic stimulation. Methods NPCs were obtained from the olfactory bulbs at embryonic day 14-16 and were transplanted into the inside border of cochlear nucleus. The host rats were divided into A and B group. After implantation, group A was raised in an augmented acoustic environment and group B in a normal condition. Migration and differentiation of the transplanted cells were observed on 14 day. Results Directional migration along auditory tracts from the graft core clearly occurred in some animals exposed to the augmented acoustic environment. Hoechst 33342, NeuN and Glutamate tri-labeled cells were found in the cochlear nuclei with immunofluorescent technic. Conclusion This observation demonstrates the survival and migration of NPCs from the olfactory bulb along the adult auditory nerve in an augmented acoustic environment following implantation.