Romand R, Zine A E, Hafidi A
Laboratoire de Neurobiologie, Université Blaise Pascal-Clermont II, Aubière, France.
Cell Motil Cytoskeleton. 1993;25(3):213-22. doi: 10.1002/cm.970250302.
This report describes the ontogenesis of cochlear stereocilia using scanning electron microscopy for analysis of cilia appearance, and fluorescence microscopy of phalloidin, a label for F-actin, to determine the maturation of the cilia framework. Surface and frozen-sectioned preparations of the otic capsule were obtained from several stages of rat pup development beginning at the 16th gestational day and at various stages until adulthood. In the earliest stage investigated, strong fluorescence labeling was visible on the apical part of Kölliker's organ, revealing a reticular outline of cell junctions. Hair cells started to differentiate at the 18th day of gestation from cells within the primordial receptor area. Phalloidin labeling revealed a sequential appearance of F-actin as the hair cells differentiated from the cells with the Kölliker's organ. The differentiation of receptor cells occurred first with the appearance of a junctional complex between the hair cell and the surrounding cells. Then a cuticular plate appeared followed by the progressive emergence of stereocilia. The F-actin labeling also revealed a progressive differentiation of receptor cells from the cochlear base to its apex. There was also an inner to outer hair cell developmental gradient of label. Inner hair cells developed stereocilia before outer hair cells. The third row of outer hair cells was the last to acquire stereocilia. The adult pattern of stereocilia was reached around the 6th postnatal day. We conclude that the appearance of actin filaments in developing receptor cells and the emergence of stereocilia can be regraded as markers for correlating function and other structural differentiation.
本报告描述了使用扫描电子显微镜分析纤毛外观以及用鬼笔环肽（一种F-肌动蛋白标记物）进行荧光显微镜观察以确定纤毛框架成熟度的情况下，耳蜗静纤毛的个体发生过程。从妊娠第16天开始直至成年的不同阶段，获取了大鼠幼崽发育几个阶段的耳囊表面和冰冻切片标本。在最早研究的阶段，在柯蒂器的顶端可见强烈的荧光标记，显示出细胞连接的网状轮廓。毛细胞在妊娠第18天从原始感受器区域内的细胞开始分化。鬼笔环肽标记显示，随着毛细胞从柯蒂器的细胞中分化出来，F-肌动蛋白依次出现。感受器细胞的分化首先表现为毛细胞与周围细胞之间出现连接复合体。然后出现角质板，随后静纤毛逐渐出现。F-肌动蛋白标记还显示感受器细胞从耳蜗底部到顶部逐渐分化。标记物也存在从内毛细胞到外毛细胞的发育梯度。内毛细胞比外毛细胞先发育出静纤毛。第三排外毛细胞是最后获得静纤毛的。出生后第6天左右达到静纤毛的成年模式。我们得出结论，发育中的感受器细胞中肌动蛋白丝的出现和静纤毛的出现可被视为将功能与其他结构分化相关联的标志物。
