Matsuda Yoshiko, Kamada Takashi, Murata Kenji, Kotani Junichiro
Department of Anesthesiology, Osaka Dental University, Osaka 540-0008.
Masui. 2004 Sep;53(9):989-93.
Upper airway reflexes include a reflex protecting the airway as well as another one dilating the airway. The latter reflex, the pharyngeal dilator reflex to negative airway pressure (NPAR), plays an important role in maintaining airway patency, although the peripheral receptors involved in NPAR have not been specified.
The effects of surface anesthesia of the pharyngeal mucous membrane on NPAR were evaluated by observing activity of the musculus genioglossus (GG) in rabbits. Following anesthesia with thiopental, two incisions were made on the trachea of each rabbit. Through these incisions, a tube connected to the anesthetic circuit was inserted into the lung and another tube connected to an aspirator into the pharynx. Effects of negative pressure on the myelogram of the GG were recorded with and without surface anesthesia with 1% lidocaine.
Electric discharge from the GG was increased in the sessions with exposure to negative pressure without surface anesthesia, but was significantly decreased in those with surface anesthesia.
These findings suggest that the peripheral receptors of NPAR are located in the pharyngeal mucous membrane.
上呼吸道反射包括保护气道的反射以及另一种扩张气道的反射。后一种反射，即气道负压引起的咽扩张肌反射（NPAR），在维持气道通畅方面起着重要作用，尽管参与NPAR的外周感受器尚未明确。
通过观察兔颏舌肌（GG）的活动来评估咽黏膜表面麻醉对NPAR的影响。用硫喷妥钠麻醉后，在每只兔的气管上做两个切口。通过这些切口，将一根连接麻醉回路的管子插入肺内，另一根连接吸引器的管子插入咽部。记录在使用和不使用1%利多卡因表面麻醉的情况下负压对GG肌电图的影响。
在未进行表面麻醉而暴露于负压的实验中，GG的放电增加，但在进行表面麻醉的实验中显著减少。
这些发现表明NPAR的外周感受器位于咽黏膜。
