FUNCTION OF THE EFFERENT VESTIBULAR SYSTEM

传出前庭系统的功能

• 批准号: 6626877
• 负责人: JAY M GOLDBERG
• 金额: $ 30.5万
• 依托单位: UNIVERSITY OF CHICAGO
• 依托单位国家: 美国
• 财政年份: 1999
• 资助国家: 美国
• 起止时间: 1999-01-01 至 2003-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6626877
• 关键词: Saimiri; afferent nerve; barbiturates; brain stem; chinchilla; denervation; ear hair cell; efferent nerve; electrophysiology; electrostimulus; head movements; immunocytochemistry; neural transmission; proprioception /kinesthesia; vestibular pathway

Vestibular organs are provided with a rich efferent innervation, originating in the brain stem. The long-term objective of this study is to understand the function of the efferent vestibular system (EVS) in the processing of vestibular information. There are three specific aims: 1) To determine the effects of electrical activation of different efferent contingents on the several afferent groups in the barbiturate- anesthetized chinchilla. The problem was originally investigated almost 20 years ago. There is a need to update results by taking into account recent findings on the organization on afferent and efferent pathways, as a recent suggestions that EVS stimulation may have more heterogeneous influence on afferent gain than had been suspected. This study provides essential background information concerning the function of the EVS. 2) To study potential long-term or trophic efferent influences by comparing the acute and chronic effects on afferent discharge on eliminating the efferent innervation or the contralateral labyrinth. The presence of neuroactive peptides and metabotrophic receptors, as well as certain features of the response to electrical stimulation suggests that the EVS exerts such an influence, yet the problem has not been previously addressed. 3) To determine the conditions leading to the discharge of efferent neurons and to efferent-mediated changes in afferent transmission. Recordings will be made from vestibular-nerve afferents and from efferent neurons within the brain stem in alert squirrel monkeys free to move their heads in a horizontal plane. For both groups of neurons, responses to active and passive head movements will be compared. The possibility that efferents get inputs from the neck, from other proprioceptors or from several vestibular organs will be explored. Some information on vestibular inputs to the EVS are best obtained in acute preparations; these experiments will be done in decerebrate chinchillas.

前庭器官具有丰富的传出神经支配，起源于脑干。这项研究的长期目的是了解前庭系统（EV）在前庭信息处理中的功能。有三个特定的目的：1）确定不同传出偶然的电动激活对巴比妥酸盐麻醉龙骨中几个传入基团的电动激活的影响。这个问题最初是在大约20年前进行的。有必要考虑到有关该组织关于传入和传染性途径的最新发现，因此有必要更新结果，因为最近提出的关于电动汽车刺激的建议可能对传入增益产生的影响比所怀疑的更多。这项研究提供了有关电动汽车功能的基本背景信息。 2）通过比较消除传入的神经支配或对侧迷宫的急性和慢性影响，研究潜在的长期或营养传播影响。神经活性肽和代谢性受体的存在以及对电刺激反应的某些特征表明，电动汽车会施加这种影响，但该问题尚未得到解决。 3）确定导致传出神经元排出的条件以及传入传播的传出变化。记录将由前庭障碍传入和大脑茎中的传出神经元进行，以在警觉的松鼠猴子中自由地在水平面上移动头部。对于两组神经元，将比较对主动和被动头部运动的反应。传出者会从颈部，其他原始受体或几个前庭器官中获得输入的可能性。关于电动汽车的前庭输入的一些信息最好在急性制备中获得；这些实验将在杂交龙猫中进行。