RESPIRATORY RELATED MOTOR OUTPUT TO UPPER AIRWAY MUSCLES

这项拟议的研究是基于喉咙的一般假设 而表现出呼气时相活动的咽肌具有 呼吸在生理和生理环境中的重要调节作用 病理生理状态。以前的动物和人类研究从这个和 其他实验室表明，喉内收肌的作用很大。 刹车呼气调节肺活量和呼气时间。在……里面 与喉内收肌相比，人们对喉内收肌的了解相对较少。 控制咽肌呼气时相活动的因素 如咽缩肌(PC)及其在 呼吸。据推测，PC肌收缩呼吸道 据推测，它们促进了上呼吸道的关闭 睡吧。相反，我们假设在咽部条件下 呼吸道变窄，PC肌肉实际上扩张并使呼吸道僵硬。 它们的扩张和硬化作用会降低呼吸道关闭压力。 帮助维持呼吸道通畅。 我们实验室之前的研究已经确定了呼吸系统- 受试者喉部内收肌的相关活动。建议数 在去大脑的猫身上设计的方案是为了测试以下几点 喉内收肌控制机制的假说 激活：1)不同的喉内收肌对 肺容量减少，2)时相和紧张性容量反馈调节肺 通过反射性地调节喉部运动输出来调节呼气时的音量 内收肌，以及3)与喉内收肌活动相关的增加 呼气末肺活量的减少主要是通过 无髓鞘胸迷走神经传入。 我们的动物模型也将被用来检验以下假设 关于PC肌肉：1)PC表现出与呼吸相关的活动 并对各种呼吸刺激做出反应，以及2)PC激活 扩张并使狭窄的咽部呼吸道变硬。前者 该假说也将在清醒状态下的正常人身上进行测试。 然后睡觉。来验证我们的假设，即PC肌肉的激活 保护而不是惩罚性的作用在维护上 睡眠期间呼吸道通畅，夜间记录PC活动 阻塞性睡眠呼吸暂停和高位睡眠患者的多导睡眠图 呼吸道阻力综合征。 拟议方案的初步结果表明，呼吸道 刺激对喉内收肌的激活有不同的影响 PC肌肉支持我们的假设，两组上呼吸道 呼气肌在控制呼吸方面有不同的作用。 然而，给定的上呼吸道肌肉的结果在以下方面非常相似 去除猫和人类受试者的大脑。在回应中的这种密切关联 将允许在动物实验中探索可能的机制 在人类身上进行的潜在观察。

The proposed research is based on the general hypothesis that laryngeal and pharyngeal muscles that exhibit phasic expiratory activity have an important role in the regulation of respiration in physiologic and pathophysiologic states. Previous animal and human studies from this and other laboratories indicate that laryngeal adductor muscles help actively brake exhalation regulating lung volume and the time of expiration. In contrast to the laryngeal adductors, relatively little is known about the factors controlling pharyngeal muscles with phasic expiratory activity such as the pharyngeal constrictor (PC) muscles and their role in respiration. It has been assumed that the PC muscles constrict the airway and it has been speculated that they promote upper airway closure during sleep. In contrast, we hypothesize that under conditions of pharyngeal airway narrowing, PC muscles actually dilate and stiffen the airway. Their dilating and stiffening action would lower airway closing pressure helping to maintain airway patency. Previous studies from our laboratory have determined the respiratory- related activity of laryngeal adductors in human subjects. The proposed protocols in decerebrate cats are designed to test the following hypotheses regarding the mechanisms controlling laryngeal adductor muscle activation: 1) different laryngeal adductors have similar responses to decreased lung volume, 2) phasic and tonic volume feedback regulate lung volume during expiration by reflexly modulating motor output to laryngeal adductors, and 3) the increase in laryngeal adductor activity associated with a decrease in end-expiratory lung volume is primarily mediated by unmyelinated thoracic vagal afferents. Our animal model will also be used to test the following hypotheses regarding the PC muscles: 1) the PCs exhibit respiratory-related activity and respond to a variety of respiratory stimuli, and 2) PC activation dilates and stiffens the narrowed pharyngeal airway. The former hypothesis will also be tested in normal human subjects during wakefulness and sleep. To test our hypothesis that activation of the PC muscles has a protective rather than a punitive role in the maintenance of upper airway patency during sleep, PC activity will be recorded during nighttime polysomnograms in patients with obstructive sleep apnea and high upper airway resistance syndrome. Preliminary results of the proposed protocols indicate that respiratory stimuli have different effects on the activation of laryngeal adductor and PC muscles supporting our hypothesis that the two sets of upper airway expiratory muscles have different roles in the control of respiration. Nevertheless, results for a given upper airway muscle are very similar in decerebrate cats and human subjects. This close correlation in responses will allow an exploration in animal experiments of the possible mechanisms underlying observations made in humans.