OPERATIONAL MECHANISMS OF AIRWAY RECEPTORS

为了完成我们之前对传入活动的研究 发源于喉部并与呼吸事件有关的我们将 喉返神经单个传入单位的记录 喉上神经的外支。这两条神经是 一般认为向声门下区供应传入神经 喉的各部分，而上喉的内侧支 喉神经(我们先前记录过的)供应 声门上结构。与跨壁相关的传入信息 喉部的压力和气流已被发现对 在维持上呼吸道通畅和调节呼吸方面的作用 图案。 冷空气、高碳酸血症混合物和喉部注水有 已发现对支气管运动活动有重要影响 呼吸模式。我们建议研究这些挑战的影响 (和低氧)对激活的喉感受器活性的影响 空气流量、跨壁压与喉内膜收缩 肌肉。我们能识别出水受体和二氧化碳受体吗？ 与我们发现的呼吸道类型中的任何一种有关吗？ 伸展受体的活性不仅取决于气道跨壁的变化 压力，还会对平滑肌活动产生影响。我们建议研究 牵张感受器活动与平滑肌的关系 一种制剂(离体胸外气管)的收缩 哪种跨壁压力保持恒定，而平滑肌活动 种类繁多(窒息、缺氧、高碳酸血症、辣椒素)。伸展感受器 记录放电时不会影响气管的马达供应 当狗自发呼吸时，肌肉。 我们将探讨经肺压力与肺功能的关系。 不同类型伸展受体对呼吸道慢适应活动的影响 气管支气管树的位置：最远端的受体 呼吸道可能与发生的跨壁压力变化“隔离” 沿航道的其他地方。在这种情况下，他们可以贡献一个 肺顺应性内稳态的额外反射机制。

In order to complete our previous studies on the afferent activity originating from the larynx and related to respiratory events we will record from single afferent units in the recurrent laryngeal nerve and the external branch of the superior laryngeal nerve. These 2 nerves are generally thought to supply the afferent innervation to infraglottic portions of the larynx, whereas the internal branch of the superior laryngeal nerve (from which we have previously recorded) supplies supraglottic structures. Afferent information related to transmural pressure and airflow in the larynx has been found to exert a significant role in the maintenance of upper airway patency and in regulating breathing pattern. Cold air, hypercapnic mixtures and instillation of water in the larynx have been found to have important influences on bronchomotor activity and breathing pattern. We propose to study the effects of these challenges (and that of hypoxia) on the activity of laryngeal receptors activated by air flow, transmural pressure and the contraction of intrinsic laryngeal muscles. Can we identify the water receptors and carbon dioxide receptors with any of the respiratory types we have found? Stretch receptors activity depends not only on changes of airway transmural pressure, but also on smooth muscle activity. We propose to study the relationship between stretch receptor activity and smooth muscle contraction in a preparation (isolated "in vivo" extrathoracic trachea) in which transmural pressure is kept constant and smooth muscle activity is varied (asphyxia, hypoxia, hypercapnia, capsaicin). Stretch receptor discharge is recorded without impairing the motor supply to the trachealis muscle while the dog breathes spontaneously. We will explore the relationship between transpulmonary pressure and activity of airway slowly adapting stretch receptors having different locations along the tracheobronchial tree: receptors in the most distal airways may become "isolated" from transmural pressure changes occurring elsewhere along the airways. They could, in this condition, contribute an additional reflex mechanism to lung compliance homeostasis.