Leonova E V, Raphael Y
Kresge Hearing Research Institute, Department of Otolaryngology, University of Michigan, Ann Arbor 48109-0648, USA.
Hear Res. 1997 Nov;113(1-2):14-28. doi: 10.1016/s0378-5955(97)00130-5.
The reticular lamina creates an ion barrier, withstands mechanical stress in the organ of Corti and is able to maintain its integrity during and after severe hair cell loss. Tight junctions maintain the ionic gradient whereas adherens junctions and the cytoskeleton are responsible for the integrity and mechanical resistance of tissues. In this study we used immunofluorescence and electron microscopy to examine the distribution of proteins of tight junctions (cingulin), adherens junctions (E-cadherin, alpha- and beta-catenin) and the cytoskeleton (actin, cytokeratin and tubulin) in whole-mounts of the normal and ototoxically damaged organ of Corti. In normal ears the proteins of adherens junctions were found in all cell types of the reticular lamina. We now demonstrate that all cells forming the reticular lamina partially overlap each other organizing extensive cell contacts with a complex three-dimensional shape. During scar formation, the tight junctions as well as adherens junctions between hair and supporting cells appeared in two distinct focal planes, which could help to preserve the ionic barrier and tissue integrity during hair cell degeneration. During scar formation all cytoskeletal structures in the reticular lamina were reorganized in a specific spatio-temporal pattern. We present a three-dimensional model of cell contact organization in the reticular lamina of normal ears and during scar formation.
网状板形成离子屏障，承受柯蒂器中的机械应力，并能在严重毛细胞损失期间及之后保持其完整性。紧密连接维持离子梯度，而黏附连接和细胞骨架则负责组织的完整性和机械抗性。在本研究中，我们使用免疫荧光和电子显微镜来检查正常及耳毒性损伤的柯蒂器整装标本中紧密连接蛋白（cingulin）、黏附连接蛋白（E-钙黏蛋白、α-连环蛋白和β-连环蛋白）以及细胞骨架蛋白（肌动蛋白、细胞角蛋白和微管蛋白）的分布。在正常耳中，黏附连接蛋白存在于网状板的所有细胞类型中。我们现在证明，形成网状板的所有细胞彼此部分重叠，形成具有复杂三维形状的广泛细胞接触。在瘢痕形成过程中，毛细胞和支持细胞之间的紧密连接以及黏附连接出现在两个不同的焦平面上，这可能有助于在毛细胞变性期间维持离子屏障和组织完整性。在瘢痕形成过程中，网状板中的所有细胞骨架结构都以特定的时空模式重新组织。我们展示了正常耳及瘢痕形成过程中网状板细胞接触组织的三维模型。
