Yonezawa S, Nodasaka Y, Kamada T, Fujita S C, Kato K, Yamada Y, Ogasawara N, Shoji R
Department of Embryology, Aichi Human Service Center, Kasugai, Japan.
Acta Otolaryngol. 1996 May;116(3):409-16. doi: 10.3109/00016489609137865.
The inner ear of mutant bustling mice, BUS/Idr, was examined histopathologically. LM examinations revealed an age-dependent degeneration of the auditory organ of Corti in BUS homozygotes, but not heterozygotes. Cochlear base-to-apex gradient in severity of the degeneration was noted. First signs of degeneration were found in the outer hair cells of the cochlear basal turn at about 3 weeks of age, followed by degeneration of the spiral ganglion cells which occurred slowly. As examined by SEM, stereociliary derangements of both the inner and outer hair cells were apparent in homozygotes as early as after 10 days. No normal arrays of stereocilia were found in homozygotes examined at 10 days through 6 months. The results of immunohistochemical examinations suggest that the sensory cells of the Corti's organ of homozygotes are structurally once normally innervated. No significant difference was found in the expression of protooncogene c-mos in the CNS between BUS homozygotes and control mice. We propose that BUS mice be categorized as a member of the so-called "waltzer-shaker" mutants group.
对突变型活泼小鼠（BUS/Idr）的内耳进行了组织病理学检查。光镜检查显示，BUS纯合子中柯蒂氏听觉器官存在年龄依赖性退变，而杂合子则未出现。观察到退变严重程度呈现耳蜗底至顶的梯度变化。大约在3周龄时，在耳蜗基部转弯处的外毛细胞中发现了退变的最初迹象，随后螺旋神经节细胞逐渐发生退变。扫描电镜检查显示，早在10天后，纯合子的内、外毛细胞均出现了静纤毛排列紊乱。在10天至6个月龄的纯合子中均未发现正常的静纤毛排列。免疫组化检查结果表明，纯合子柯蒂氏器官的感觉细胞在结构上曾有正常的神经支配。在中枢神经系统中，BUS纯合子与对照小鼠的原癌基因c-mos表达未发现显著差异。我们建议将BUS小鼠归类为所谓的“华尔兹-震颤”突变体组的成员。
