Department of Otolaryngology-Head and Neck Surgery, Shanghai Ninth People's Hospital, Shanghai, China.
Ear Institute, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
J Comp Neurol. 2021 Aug 1;529(11):2958-2969. doi: 10.1002/cne.25137. Epub 2021 Mar 18.
In mammalian cochlea, sound-induced vibration is amplified by a three-row lattice of Y-shaped microstructures consisting of electromotile outer hair cell and supporting Deiters cell. This highly organized structure is thought to be essential for hearing of low-level sounds. Prior studies reported differences in geometry and synaptic innervation of the outer hair cells between rows, but how these fine features are achieved at subcellular level still remains unclear. Using serial block-face electron microscopy, we acquired few-hundred-micron-sized cytoarchitecture of mouse organ of Corti at nanometer resolution. Structural quantifications were performed on the Y-shapes as well as afferent and efferent projections to outer hair cells (OHCs). Several new features, which support the previously observed inter-row heterogeneity, are described. Our result provides structural bases for the gradient of mechanical properties and diverse centrifugal regulation of OHC rows.
在哺乳动物耳蜗中，Y 形的微结构三排晶格通过动感的外毛细胞和支持的 Deiters 细胞放大声音引起的振动。这种高度组织化的结构被认为是对低水平声音听觉至关重要的。先前的研究报道了外毛细胞在排之间的几何形状和突触神经支配的差异，但这些精细特征如何在亚细胞水平上实现仍不清楚。使用连续块面电子显微镜，我们以纳米分辨率获得了小鼠耳蜗的数百微米大小的细胞结构。对 Y 形以及外毛细胞（OHC）的传入和传出投射进行了结构定量。描述了几个新的特征，这些特征支持先前观察到的排间异质性。我们的结果为 OHC 排机械性能的梯度和离心调节的多样性提供了结构基础。
