Hackney C M, Fettiplace R, Furness D N
Department of Communication and Neuroscience, Keele University, Staffordshire, UK.
Hear Res. 1993 Sep;69(1-2):163-75. doi: 10.1016/0378-5955(93)90104-9.
The stereociliary bundles of hair cells from the basilar papilla of the red-eared turtle were examined with transmission and high resolution scanning electron microscopy to provide a description of their morphology, orientation and inter-ciliary connections for comparison with physiological observations. Bundles on hair cells in the basilar membrane region are of a uniform shape and orientation, but bundles on the apical and basal limbus are distinct in having elongated kinocilia more than twice the length of the tallest stereocilia. Bundles in the basilar membrane region show a roughly two-fold increase in height from 5 to 9 microns from base to apex. Electrical recordings from isolated hair cells indicate that the bundle height is inversely proportional to the cell's characteristic frequency. It is argued that the change in dimensions is insufficient to contribute significantly to the cochlea's frequency selectivity. The cytoplasm adjacent to the kinocilium is filled with microtubules and large vesicles, and there are coated pits in the apical membrane which, it is suggested, may be indicative of rapid turnover of the membrane in this region.
利用透射电子显微镜和高分辨率扫描电子显微镜对红耳龟基底乳头毛细胞的静纤毛束进行了检查，以描述其形态、方向和纤毛间连接，以便与生理学观察结果进行比较。基底膜区域毛细胞上的静纤毛束形状和方向一致，但顶缘和基缘上的静纤毛束不同，其动纤毛细长，长度超过最高静纤毛的两倍。基底膜区域的静纤毛束高度从基部到顶端从5微米到9微米大致增加了两倍。对分离的毛细胞进行的电记录表明，静纤毛束高度与细胞的特征频率成反比。有人认为，尺寸变化不足以对耳蜗的频率选择性做出显著贡献。靠近动纤毛的细胞质充满微管和大囊泡，顶端膜上有被膜小窝，有人认为这可能表明该区域膜的快速更新。
