VESTIBULOSYMPATHETIC REFLEXES IN HUMANS

人类的前庭交感反射

• 批准号: 2901313
• 负责人: CHESTER A RAY
• 金额: $ 10.28万
• 依托单位: PENNSYLVANIA STATE UNIV HERSHEY MED CTR
• 依托单位国家: 美国
• 财政年份: 1998
• 资助国家: 美国
• 起止时间: 1998-04-01 至 2002-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/2901313
• 关键词: baroreflex; behavioral /social science research tag; clinical research; head movements; human subject; postural hypotension; sympathetic nervous system

DESCRIPTION (Adapted from the applicant's abstract): The long-term objectives of the Principal Investigator are to evaluate reflex mechanisms that regulate the cardiovascular system in humans. The investigator has recently demonstrated that head-down neck flexion (HDNF) increases muscle sympathetic nerve activity (MSNA). This finding suggested a role of the vestibular system in regulating MSNA. The overall hypothesis to be evaluated in this project is that the vestibular system plays an important role in the regulation of the sympathetic nervous system in humans. This hypothesis will be evaluated by recording MSNA in humans during activation of the vestibular system by different head movements. In this proposal the following hypotheses will be tested: 1. Increases in MSNA during HDNF are due to vestibular activation. 2. Otolith organs but not semicircular canals elicit increases in MSNA. 3. Activation of the vestibulosympathetic reflex modulates MSNA elicited by other cardiovascular reflexes. To test these hypotheses, studies with the following specific aims are proposed: 1. To determine MSNA responses to HDNF during different levels and durations of neck flexion, and performed in different body positions. 2. To determine MSNA responses during dynamic head movements which activate both the otolith organs and semicircular canals. 3. To determine the interaction of HDNF (vestibulosympathetic reflex) with other cardiovascular reflexes (e.g., arterial baroreflex) on MSNA in humans. The design of these studies will provide new knowledge regarding vestibular regulation of sympathetic activity in humans. These findings may have important implications in understanding the cause of orthostatic intolerance in otherwise healthy subjects and why orthostatic intolerance is more prevalent in the elderly and in individuals following prolonged exposure to microgravity.

描述（改编自申请人的摘要）：长期 首席研究员的目标是评估反射机制 调节人类心血管系统。 调查员有 最近证明，低头颈部屈曲（HDNF）可以增加肌肉 交感神经活动（MSNA）。 这一发现表明了 前庭系统调节 MSNA。 总体假设为 该项目评估的是前庭系统起着重要的作用 在人类交感神经系统的调节中发挥作用。 这 假设将通过在激活过程中记录人类 MSNA 来评估 通过不同的头部运动来调节前庭系统。 在此提案中 将测试以下假设： 1. HDNF 期间 MSNA 的增加是 由于前庭激活。 2. 耳石器官但不是半圆形 根管引起 MSNA 增加。 3. 前庭交感神经的激活 反射调节由其他心血管反射引起的 MSNA。 测试 根据这些假设，提出了具有以下具体目标的研究： 1. 确定 MSNA 在不同水平和持续时间内对 HDNF 的反应 颈部弯曲，并以不同的身体姿势进行。 2. 确定 MSNA 在动态头部运动期间做出反应，激活耳石 器官和半规管。 3. 确定HDNF的相互作用 （前庭交感神经反射）与其他心血管反射（例如， 动脉压力反射）对人类 MSNA 的影响。 这些研究的设计将 提供有关交感神经前庭调节的新知识 在人类中的活动。 这些发现可能具有重要意义 了解健康人体位不耐受的原因 受试者以及为什么直立不耐受在老年人中更为普遍 以及长期暴露于微重力的个体。