豚鼠耳蜗毛细胞丝状肌动蛋白表达

目的研究正常生理状态下丝状肌动蛋白(F-actin)的结构特征和分布规律。方法应用免疫细胞化学方法,采用单克隆抗体及免疫荧光标记技术,借助荧光显微镜和激光扫描共聚焦显微镜,逐层观察耳蜗毛细胞骨架蛋白-丝状肌动蛋白的分布特点。结果在连续的光学切片上,可以看到静纤毛、表皮板和外毛细胞(outerhaircells,OHCs)的周围环都有明亮的鬼笔环肽染色。除基底转外,其余各转皮板下网络(infracuticularnetwork,ICN)均有鬼笔环肽显色,外毛细胞侧壁着色亮度自基底转到顶转逐渐减弱。内、外柱细胞和Deiters细胞染色明亮,其中耳蜗各转外柱细胞头板的显色亮度都强于OHCs。结论豚鼠耳蜗OHCs中F-actin的结构和分布存在差异,内毛细胞(innerhaircells,IHCs)的结构和分布无差异,表明局部结构的梯度决定局部功能的差异。

Distribution of F-actin in the hair cells of the guinea pig cochlear as revealed by laser scanning confocal microscopyt

OBJECTIVE To investigate the distribution of F-actin along the organ of Corti. METHODS The paraform- aldehyde fixed guinea pig cochleae were stained with rhodamine-phalloidin to detect F-actin. The hair cells were studied in surface specimens of the organ of Corti with laser scanning confocal microscopy. RESULTS In the serial op- tical sections, phalloidin stained the stereocilia, cuticular plate, and a circumferential ring in the outer hair cells (OHCs). The infracuticular network of OHCs in the upper turns showed a strong reaction, but it did not appear in the basal turn. The lateral cortex of OHCs showed longitudinal gradients de- creasing in intensity from basal turn towards the apical turn. The Deiters cell, the headplates of the pillar cells and the inner pillar cells were also stained, moreover the staining intensity of the headplates of the pillar cells were stronger than OHCs in all turns. CONCLUSION The differences in the distribution and organization of F-actin among the hair cells and turns of cochlea probably reflect in their mecha- nisms of function.