Nishino T, Kohchi T, Honda Y, Shirahata M, Yonezawa T
Br J Anaesth. 1986 Aug;58(8):903-8. doi: 10.1093/bja/58.8.903.
The effects of changes in PaCO2 and PaO2 on the swallowing reflex were studied in anaesthetized, vagotomized, paralysed and artificially ventilated cats. The swallowing reflex was induced by electrical stimulation of the superior laryngeal nerve (SLN). This initially suppressed activity in the phrenic nerve (PN). The swallowing reflex was then identified by a characteristic brief burst of PN activity and a large amplitude burst of hypoglossal nerve (HN) activity. Steady-state responses to constant SLN stimulation for 60 s were measured at four carbon dioxide tensions (PaCO2 3.9, 5.1, 6.3 and 7.8 kPa) with hyperoxia (PaO2 greater than 51 kPa) and at four values of PaO2 (PaO2 56, 11.3, 6.9 and 4.8 kPa) at a fixed PaCO2 (PaCO2 4.2 kPa). Although both hypercapnia and hypoxia increased the spontaneous respiratory activity in PN and HN, the number of swallows elicited during SLN stimulation was not influenced by PaCO2, whereas a progressive decrease in the number of swallows with decreasing PaO2 was observed consistently. These results indicate that the swallowing reflex is independent of the background respiratory activity and that hypoxia depresses the swallowing reflex, whereas hypercapnia has no effect.
在麻醉、迷走神经切断、麻痹并进行人工通气的猫身上，研究了动脉血二氧化碳分压（PaCO2）和动脉血氧分压（PaO2）变化对吞咽反射的影响。通过电刺激喉上神经（SLN）诱发吞咽反射。这最初会抑制膈神经（PN）的活动。然后通过膈神经活动的特征性短暂爆发和舌下神经（HN）活动的大幅度爆发来识别吞咽反射。在四种二氧化碳分压（PaCO2 3.9、5.1、6.3和7.8 kPa）并伴有高氧（PaO2大于51 kPa）的情况下，以及在固定的动脉血二氧化碳分压（PaCO2 4.2 kPa）下的四种动脉血氧分压值（PaO2 56、11.3、6.9和4.8 kPa）时，测量对持续60秒的恒定喉上神经刺激的稳态反应。尽管高碳酸血症和低氧血症都会增加膈神经和舌下神经的自发呼吸活动，但在喉上神经刺激期间诱发的吞咽次数不受PaCO2的影响，而随着PaO2降低，吞咽次数持续逐渐减少。这些结果表明，吞咽反射独立于背景呼吸活动，低氧会抑制吞咽反射，而高碳酸血症则无影响。
