Influence of intralaryngeal CO2 on the response of laryngeal afferents to upper airway negative pressure.
Influence of intralaryngeal CO2 on the response of laryngeal afferents to upper airway negative pressure.
复制标题
喉内CO2 对喉传入上气道负压反应的影响。
DOI：
10.1152/jappl.1994.76.6.2720
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发表时间：
1994
期刊：
影响因子：
--
通讯作者：
Mathew,OP
中科院分区：
文献类型：
--
作者：
Ghosh,TK;Mathew,OP
研究了20只麻醉自主呼吸的成年猫咽内CO2对喉上传入神经对负压反应的影响。记录喉上神经外周切端单纤维动作电位。当动物对着闭塞的上呼吸道呼吸时，吸气时喉部暴露在负压下。在99个被评估的受体中，54个是呼吸调节性的，45个是非调节性的。通过将喉部暴露于二氧化碳或空气中1分钟，然后立即阻塞上呼吸道，确定了咽内二氧化碳对39个受体对负压反应的影响。受负压抑制的22条纤维在空气试验中的平均放电频率为32.4 +/- 2.6 Hz，而在CO2试验中为29.9 +/- 2.6 Hz （P < 0.005）。在热湿空气试验后上呼吸道闭塞期间，这些末端的放电频率降至24.2 +/- 2.3 Hz，而CO2试验后为17.5 +/- 2.2 Hz （P < 0.001）。在空气和二氧化碳试验中，17根纤维在负压刺激下的平均放电频率分别为3.7 +/- 2.6 Hz和4.4 +/- 1.8 Hz。上呼吸道闭塞时平均频率分别为14.7 +/- 3.5 Hz（空气）和18.6 +/- 4.0 Hz (CO2) （P < 0.01）。我们的结论是，咽内CO2可以改变压力敏感的喉部传入事件的反应，从而在维持上气道通畅中起作用。（摘要删节250字）
Effects of intralaryngeal CO2 on the response of superior laryngeal afferents to negative pressure were investigated in 20 anesthetized spontaneously breathing adult cats. Single-fiber action potentials were recorded from the peripheral cut end of the superior laryngeal nerve. The larynx was exposed to negative pressure during inspiration when the animal breathed against an occluded upper airway. Among the 99 receptors evaluated, 54 were respiratory modulated and 45 were nonmodulated endings. The effect of intralaryngeal CO2 on the response of 39 receptors responding to negative pressure was determined by exposure of the larynx to CO2 or air for 1 min followed immediately by upper airway occlusion. The mean discharge frequency of 22 fibers inhibited by negative pressure was 32.4 +/- 2.6 Hz during air trials compared with 29.9 +/- 2.6 Hz during CO2 trials (P < 0.005). During occlusion of the upper airway after the warm humidified air trial, the discharge frequency of these endings decreased to 24.2 +/- 2.3 Hz compared with 17.5 +/- 2.2 Hz after CO2 trial (P < 0.001). The mean discharge frequencies of 17 fibers stimulated by negative pressure were 3.7 +/- 2.6 and 4.4 +/- 1.8 Hz, respectively, during air and CO2 trials. The mean frequencies increased to 14.7 +/- 3.5 Hz (air) and 18.6 +/- 4.0 Hz (CO2) during upper airway occlusions (P < 0.01). We conclude that intralaryngeal CO2 can alter the response of pressure-sensitive laryngeal afferents, thereby having a role in the maintenance of upper airway patency.(ABSTRACT TRUNCATED AT 250 WORDS)