NEURAL CONTROL RESPIRATORY MUSCLES DURING EXPIRATION

呼气期间神经控制呼吸肌

• 批准号: 3355040
• 负责人: ERIK VAN LUNTEREN
• 金额: $ 10.73万
• 依托单位: CASE WESTERN RESERVE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 1987
• 资助国家: 美国
• 起止时间: 1987-07-01 至 1992-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3355040
• 关键词: anesthesia; bronchospasm; cats; chemoreceptors; diaphragm; dogs; electromyography; electrophysiology; mechanoreceptors; motor neurons; muscle contraction; neural information processing; neurophysiology; posture; pulmonary respiration; respiration regulatory center; respiratory airway pressure; respiratory gas transport; respiratory hypoxia; respiratory muscles; respiratory pharmacology; respiratory reflex; single cell analysis

Active control of expiratory airflow by the respiratory muscles influences gas exchange, the degree of emptying of the lungs, and the work of breathing; may help optimize inspiratory muscle function; and is important during coughing and speech. Alterations in expiratory timing and velocity of flow occur in response to hypoxia, hypercapnia and exercise, and in diseases such as asthma, chronic obstructive pulmonary disease and sleep apnea. Recent studies of medullary and pontine respiratory centers suggest that neurophysiologically expiration may consist of tow distinct phases. In the proposed studies we will focus on the peripheral mechanisms by which abdominal, thoracic and upper airway muscles actively modulate expiration during these two phases. Specifically, in anesthetized dogs and cats we will 1) examine the manner in which multiple abdominal and thoracic expiratory muscles act in a coordinated fashion during resting and stimulated breathing; 2) study the relationship between the late expiratory activity of the above muscles and the early expiratory activity of the thoracic inspiratory muscles; 3) assess the extent to which upper airway dilators and constrictors are reciprocally active during the two phases of expiration, and how this os modified by respiratory stimuli; 4) record activity from single motor units of selected respiratory muscles, and examine how different motor unit subpopulations fire during expiration; and 5) assess the relationship between expiratory electrical activity of the above muscles and the mechanical consequences of muscle contraction, including respiratory changes in muscle length, expiratory flow rates and respiratory pressures. Studies will be performed during eupnea, when breathing is stimulated by hypercapnia and hypoxia, and following bronchoconstriction; in addition we will assess the roles that different chemoreceptors and mechanoreceptors play in mediating the responses to these stimuli. Finally, in chronically instrumented awake cats we will analyze expiratory activity recorded from several abdominal, thoracic and upper airway muscles to 1) ensure that conclusions derived from studies in anesthetized animals are not unduly influenced by the effects of anesthesia, and 2) assess the effects of spontaneous changes in posture on respiratory muscle activity during expiration.

呼吸肌对呼气气流的主动控制 影响气体交换，肺排空的程度，以及 呼吸的功；可能有助于优化吸气肌 功能；在咳嗽和说话时很重要。 呼气时间和流速的改变发生在 对缺氧、高碳酸血症和运动的反应，以及在疾病中的反应 如哮喘、慢性阻塞性肺疾病和睡眠 呼吸暂停。延髓和桥脑呼吸系统的研究近况 研究中心认为，神经生理学呼气可能包括 两个截然不同的阶段。在拟议的研究中，我们将重点放在 腹壁、胸壁和胸壁的外周机制 在这些过程中，上呼吸道肌肉积极调节呼气 分两个阶段。具体地说，在麻醉的狗和猫身上，我们将1) 检查多个腹部和胸部的方式 呼气肌在休息和休息时协调动作。 刺激性呼吸；2)研究晚期精神分裂症患者 上述肌肉的呼气活动和呼气早期 胸腔吸气肌的活动；3)评估程度 上呼吸道扩张器和缩窄器是相互作用的 在到期的两个阶段中处于活动状态，以及这是如何操作的 通过呼吸刺激进行修改；4)记录单次 所选呼吸肌的运动单位，并检查如何 不同的运动单位亚群在到期时触发；以及5) 评估呼气性电活动与脑电活动的关系 上述肌肉和肌肉的力学后果 收缩，包括肌肉长度的呼吸变化， 呼气流速和呼吸压力。研究将会是 在真呼吸暂停期间进行，当呼吸受到刺激时 高碳酸血症和低氧，以及随后的支气管收缩； 此外，我们还将评估不同的化学感受器 机械感受器在调节对这些反应的反应中发挥作用 刺激物。最后，在长期使用仪器的清醒猫科动物中，我们将 分析从几个腹部记录的呼气活动， 胸部和上呼吸道肌肉以1)确保结论 从麻醉动物的研究中得出的结论并不过分 受麻醉效果的影响，以及2)评估效果 体位自发变化对呼吸肌活动的影响 在有效期内。