FUNCTION OF THE MACULA LAGENA

黄斑的功能

• 批准号: 2128010
• 负责人: SHERRI M JONES
• 金额: $ 3.2万
• 依托单位: UNIVERSITY OF MISSOURI-COLUMBIA
• 依托单位国家: 美国
• 财政年份: 1995
• 资助国家: 美国
• 起止时间: 1995-01-01 至 1996-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/2128010
• 关键词: Aves; afferent nerve; auditory stimulus; electrophysiology; gravity; growth /development; histology; microelectrodes; neuroanatomy; neurons; otocyst /otolith; sensory receptors; single cell analysis; species difference; vibration

The avian macula lagena is a markedly curved otolithic organ located at the distal tip of the cochlear duct. It is physically distinct from the auditory organ, the basilar papilla. Anatomical descriptions of the sensory organ and its neural projections to the brainstem suggest that the macula lagena may be a gravity receptor similar to the other otolithic organs of the vestibular system. It has been shown that the avian macula lagena does not likely contribute to auditory function, and lagena afferents predominately exhibit a regular spontaneous activity pattern. However, the natural or adequate stimulus for lagenar afferents has not been determined. The purpose of the present research is to test the hypothesis that the avian macula lagena is a gravity receptor. The following questions will be addressed: 1) Are primary afferents of the avian macula lagena responsive to gravity and/or vibration? If so, what are the effects of changing the direction of the gravity vector and/or the amplitude of vibration?; and 2) To what position within the avian macula lagena do characterized neurons project: To do this we will record single unit activity from primary afferents of the lagenar macula in one- to two-week old chickens (Gallus domesticus) and characterize the firing patterns of these neurons to static tilts and vibration. The characterized neurons will then be injected with biocytin to determine the neural projections to the lagena. These data will be compared and contrasted with data available for otolithic receptors of lower and higher vertebrate species. New insights will be gained concerning the avian macula lagena specifically. This in turn will provide the basis for a better understanding of how different gravity receptors might work. A more complete understanding of the functional types of neurons present in the lagena will contribute significantly to our understanding of scalp recorded short latency vestibular evoked potentials. These data will also be used in formulating questions and strategies for future research which will focus on detailed analyses of lagenar physiological responses to gravitational and vibratory stimuli. Future research efforts will be directed towards identifying and comparing physiological roles of the maculae lagena, utriculi, and sacculi, as input sensors to the avian motor control system. In addition, we will seek to understand embryonic development of these organs and factors that influence their ontogeny.

鸟类的lagena斑是一个明显弯曲的耳石器官，位于 耳蜗管的末端 它在物理上不同于 听觉器官，基底乳头。 解剖学描述 感觉器官及其对脑干的神经投射表明， 黄斑可以是与另一个类似的重力感受器 前庭系统的耳石器官。 已显示 鸟类lagena斑不太可能有助于听觉功能， 壶腹传入神经主要表现出有规律的自发活动 格局 然而，对lagenar传入神经的自然或适当刺激 尚未确定。 本研究的目的是检验假设， 鸟类的lagena斑是重力感受器。 以下问题将 1）是鸟类lagena斑的主要传入神经 对重力和/或振动有反应吗 如果是， 改变重力矢量的方向和/或 振动？（2）在鸟类的壶腹斑中， 特征神经元项目：要做到这一点，我们将记录单个单位 lagenar macula的初级传入神经在一到两周内的活动 老鸡（原鸡）和特征的射击模式， 这些神经元对静态倾斜和振动的反应。 特征神经元 将被注射生物胞素以确定神经投射 去拉热纳。 这些数据将与下列数据进行比较和对比： 低等和高等脊椎动物物种的耳石受体。 新的见解 将获得关于禽斑lagena具体。 这 反过来将提供基础，更好地了解如何不同的 重力感应器可能会起作用 更完整地理解 存在于壶腹中的神经元的功能类型将有助于 对我们理解头皮记录的短潜伏期有重要意义 前庭诱发电位 这些数据也将用于 为未来的研究提出问题和战略， 详细分析了拉格纳对重力的生理反应， 和振动刺激。 未来的研究工作将致力于 鉴定和比较黄斑的生理作用， 椭圆囊和球囊作为鸟类运动控制的输入传感器 系统 此外，我们将寻求了解胚胎发育 这些器官和影响它们个体发育的因素。