Bradford A, McKeogh D, O'Regan R G
Department of Physiology, Royal College of Surgeons in Ireland.
J Appl Physiol (1985). 1998 Sep;85(3):1135-41. doi: 10.1152/jappl.1998.85.3.1135.
We compared the effects of CO2 applied continuously and during expiration on laryngeal-receptor activity in paralyzed, artificially ventilated and nonparalyzed, spontaneously breathing cats by using an isolated larynx, artificially ventilated to approximate a normal respiratory cycle. The majority of quiescent negative-pressure and all cold receptors were excited by 5 and 9% CO2 applied both continuously and during expiration. In general, quiescent positive-pressure, tonic negative-pressure, and tonic positive-pressure receptors were inhibited by 5 and 9% CO2 applied continuously and during expiration. There were no significant differences between responses to 5 and 9% CO2 or to continuous and expired CO2 or between paralyzed and nonparalyzed preparations. In conclusion, laryngeal receptors respond to changes in CO2 concentration occurring during a normal respiratory cycle. Because laryngeal-receptor stimulation exerts reflex effects on ventilation and upper airway muscle activity, these results suggest that airway CO2 plays a role in reflex regulation of breathing and upper airway patency.
我们通过使用一个分离的、人工通气以模拟正常呼吸周期的喉，比较了在麻痹、人工通气的猫以及未麻痹、自主呼吸的猫中，持续给予二氧化碳和在呼气时给予二氧化碳对喉感受器活动的影响。大多数静态负压感受器和所有冷感受器在持续给予以及呼气时给予5%和9%二氧化碳时均被激活。一般来说，静态正压感受器、紧张性负压感受器和紧张性正压感受器在持续给予以及呼气时给予5%和9%二氧化碳时均受到抑制。对5%和9%二氧化碳的反应、对持续给予和呼气时给予二氧化碳的反应以及麻痹和未麻痹标本之间的反应均无显著差异。总之，喉感受器对正常呼吸周期中发生的二氧化碳浓度变化有反应。由于喉感受器刺激对通气和上气道肌肉活动产生反射效应，这些结果表明气道二氧化碳在呼吸和上气道通畅的反射调节中起作用。
