HEARING LOSS AND AGING IN THE AUDITORY SYSTEM

本研究将调查进行性听力损失和相关的 随着年龄的增长，听觉通路中的细胞变化。 这项工作将 补充一个正在进行的，资助的NIH计划项目的基础上， 首席研究员部门。 该项目致力于 在一个定义明确的模型中， 猕猴（Macaca mulatta）。 当前 拟议的研究计划将利用计划项目动物携带 输出相关的功能（诱发电位）和结构（fight和 电子显微镜）研究老化的猴子听觉系统。 所有 可用的人类听觉随年龄下降（老年性聋）的动物模型， 恒河猴提供了最合适的模型，由于它的寿命， 与人类听觉系统的功能和结构相似， 它的听觉老化。 现在有机会研究听觉 这群猴子的老龄化是前所未有的， 在可预见的未来再次可用。 将在每只动物中研究音调诱发的脑干听觉电位， 在计划项目牺牲之前，为了评估 听力状态 处死后，详细的形态学研究将 在上级橄榄内的细胞群上进行 复杂，下丘，和听觉皮层;此外，损失 耳蜗和螺旋神经节细胞的受体细胞的数量将 评估。 利用光镜和电镜免疫细胞化学， 以及传统的细胞形态学技术，研究将旨在摆脱 通过分析外周和中央细胞损失， 细胞变性的发生和随后的克里思和严重程度，以及 免疫原性随年龄下降（使用，例如，钙结合蛋白， 细胞骨架和GABA抗体）。 几乎所有的分析都将 代表了第一个这样的研究老年急性变化，在这一重要的 动物模型

This study will investigate progressive hearing loss and the correlated cellular changes in the auditory pathway with advancing age. The work will be complementary to an ongoing, funded NIH Program Project based in the Principal Investigator's department. This Program Project is devoted to the analysis of a variety of neural changes with age in a well-defined population of aging rhesus monkeys (Macaca mulatta). The presently proposed research program will utilize the Program Project animals to carry out correlated functional (evoked potential) and structural (fight and electron microscopic) studies of the aging monkey auditory system. Of all available animal models of human auditory decline with age (presbyacusis), the rhesus monkey provides the most apt model, by virtue of its lifespan, functional and structural similarity to the human auditory system, and what is known of its auditory aging. The present opportunity to study auditory aging in this monkey population is an unparalleled one, and is not likely to be available again in the foreseeable future. Tone-evoked brainstem auditory potentials will be studied in each animal, immediately prior to sacrifice by the Program Project, in order to assess hearing status. Following sacrifice, detailed morphological studies will be carried out on the cell population's within the superior olivary complex, inferior colliculus, and auditory cortex; in addition, the losses of receptor cells of the cochlea and spiral ganglion cells will be evaluated. Using light and electron microscopic immunocytochemistry, as well as conventional cytomorphological techniques, studies will aim to shed light on human presbyacusis by analyzing peripheral and central cell loss, the genesis and subsequent tempo and severity of cellular degeneration, and declines with age in immunogenicity (using, e.g., calcium binding protein, cytoskeletal, and GABA antibodies). Almost all of the analyses will represent the first such studies of presbyacutic changes in this important animal model.