Smad5基因在小鼠耳蜗胚胎发育中的作用  

Role of Smad5 in the embryonic development of the mouse cochlea

作　　者：宇雅苹[1] 杨仕明[1] 胡吟燕[1] 郭维[1] 孙建和[1] 于宁[1] 韩东一[1] 杨伟炎[1] 

机构地区：[1]解放军耳鼻咽喉研究所解放军总医院耳鼻咽喉头颈外科,北京100853

出　　处：《中华耳科学杂志》2006年第3期186-189,共4页Chinese Journal of Otology

基　　金：国家自然科学基金(30571017;30000189);军队"十五"科研基金(01Q050);北京市自然科学基金(7042061)资助

摘　　要：目的检测Smad5基因在小鼠耳蜗胚胎发育中的作用。方法选用耳廓反应灵敏、健康的C57BL/6小鼠作为种鼠交配,用观察阴栓方法获得胚胎9天到20天的胎鼠,≤17天取胚胎头,≥18天在显微镜下取耳蜗,胚胎头水平冰冻切片,耳蜗平行于蜗轴冰冻切片,HE染色方法观察小鼠内耳发育形态演变过程,免疫组织化学方法检测Smad5蛋白在小鼠胚胎10～20天的表达情况。结果胚胎10天,听泡发育,胚胎12天听泡下部有蜗管始基形成并开始发育。胚胎18天,蜗管发育了2圈,形成了可以辨认的内、外毛细胞,血管纹开始分化。Smad5在小鼠内耳胚胎发育全程均有阳性表达,且表达比较广泛,尤其早期在整个听囊均有表达。在胚胎15～17天,主要集中在即将发育成基底膜听觉感受器的部分。在胚胎发育中后期在内外毛细胞、螺旋神经节细胞、支持细胞、血管纹、基底膜、前庭膜等也有表达。结论Smad5参与小鼠耳蜗胚胎发育全过程,它可能为听觉的发生所必需的基因。To explore the role of Smad5 in the development process of the embryonic mouse cochlea. Methods Embryos were isolated from timed-pregnant C57BL/6 mice （1 dpc=Vaginal plug）. Frozen sections from embryos were processed for HE staining to observe the morphological change of embryonic mouse cochlea and for immunohistochemistry to determine the expression of Smad5. Results At the tenth day of gestation the otocyst was a closed ovoid sac. The cochlear duct started to develop at the twelfth day of gestation as an extension of the ventral part of the otocyst. At the eighteenth day the inner and outer hair cells were identified. Smad5 gene was expressed extensively in the cochlea throughout the whole gestation. From the fifteenth to seventeenth day Smad5 expression was concentrated in the part to be going to develop into auditory receptor organ on the basal membrane. Later, Smad5 was expressed in the supporting cells, hair cells, spiral ganglion, Reissner＇s membrane and epithelium of stria vascularis. Conclusion The Smad5 exists in the mouse cochlea throughout the whole gastation and might play an important role in the development of mouse inner ear.

关 键 词：Smad5基因 内耳 发育 耳蜗 C57小鼠 免疫组化 

分 类 号：R394.11[医药卫生—医学遗传学] R321.59[医药卫生—基础医学]