COCHLEAR NERVE DEVELOPMENT

耳蜗神经发育

• 批准号: 3461577
• 负责人: STEPHEN M ECHTELER
• 金额: $ 8.95万
• 依托单位: NORTHWESTERN UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 1990
• 资助国家: 美国
• 起止时间: 1990-03-01 至 1995-02-28
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3461577
• 关键词: auditory stimulus; cochlear nerve; developmental neurobiology; electron microscopy; electrophysiology; ganglions; gerbil /jird; hearing; histology; innervation; neurons; newborn animals; organ culture; organ of Corti; sound frequency; stimulus /response; synapses

This study will examine the postnatal changes in structure and function of mammalian cochlear neurons which underlie the maturation of hearing. The development of cochlear innervation patterns will be charted in an age- graded series of neonatal gerbils using standard in vivo and newly devised in vitro Horseradish peroxidase tract-tracing methods applied to intact and acutely-excised cochleae. Parallel in vitro studies of the development of cochlear neuron arbors in long-term organotypic cultures of the gerbil organ of Corti will examine the potential role of neuronal competition between developing cochlear afferents and efferents in sculpting a mature pattern of cochlear hair cell innervation. The ultrastructural events which guide the formation and pruning of cochlear neuron arbors with their target hair cells will be studied in both intact and cultured cochleae by serial reconstruction of selected HRP- labeled afferent terminals using high voltage electron microscopy (HVEM). Postnatal changes in the response properties of cochlear neurons to sound will be explored at specific sites within the cochlear spiral using a new spiral ganglion cell recording approach in neonatal gerbils. Over a quarter of a million children in this country are hearing impaired due to some form of congenital sensorineural hearing loss. The proposed studies should provide crucial normative data which are required for understanding the mechanisms by which disease alters the development of structure and function in the auditory periphery.

本研究将检查产后结构和功能的变化 哺乳动物耳蜗神经元是听力成熟的基础。 这 耳蜗神经支配模式的发展将在一个年龄阶段被绘制出来 使用体内标准和新设计的新生儿沙鼠分级系列 体外辣根过氧化物酶路径追踪方法应用于完整和 急性切除的耳蜗。 耳蜗神经元乔木发育的平行体外研究 沙鼠柯蒂器官的长期器官型培养将检查 发育中的耳蜗之间神经元竞争的潜在作用 传入和传出神经塑造耳蜗毛细胞的成熟模式 神经支配。 指导形成和修剪的超微结构事件 耳蜗神经元轴及其目标毛细胞将在两个方面进行研究 通过选定的 HRP- 的连续重建来完整和培养的耳蜗 使用高压电子显微镜（HVEM）标记传入终端。 耳蜗神经元对声音的反应特性的出生后变化 将使用新的方法在耳蜗螺旋内的特定部位进行探索 新生儿沙鼠螺旋神经节细胞记录方法。 这个国家有超过 25 万儿童有听力障碍 由于某种形式的先天性感音神经性听力损失。 拟议的 研究应提供必要的关键规范数据 了解疾病改变发展的机制 听觉外围的结构和功能。