Strohl K P, Norcia M P, Wolin A D, Haxhiu M A, van Lunteren E, Deal E C
Department of Medicine, Case Western Reserve University, Cleveland, Ohio 44106.
J Appl Physiol (1985). 1988 Aug;65(2):870-7. doi: 10.1152/jappl.1988.65.2.870.
Respiratory chemical and reflex interventions have been shown to affect nasal resistance or tracheal tone, respectively. In the present study, nasal caliber (assessed from pressure at a constant flow) and tracheal tone (assessed from pressure in a fluid-filled balloon within an isolated tracheal segment) were monitored simultaneously in anesthetized, paralyzed, artificially ventilated (inspired O2 fraction = 100%) cats. We examined the effect of CO2 inhalation and sciatic nerve stimulation as well as the application of nicotine (6 X 10(-4) mol/l) or lidocaine (2% solution) to the intermediate area of the ventral medullary surface (VMS). CO2 and VMS nicotine resulted in a significant increase in tracheal pressure [147 +/- 73 and 91 +/- 86% (SD), respectively]; and a significant reduction in nasal pressure (-35 +/- 10 and -20 +/- 13%, respectively). In contrast, sciatic nerve stimulation resulted in a significant fall in both tracheal (-50 +/- 36%) and nasal pressure (-21 +/- 13%). Application of 2 or 4% lidocaine to the VMS reduced tracheal pressure but did not significantly affect nasal pressure. After VMS lidocaine, nasal and tracheal responses to CO2, sciatic nerve stimulation, or VMS nicotine, when present, were negligible. These results suggest a role for the VMS in the regulation and coordination of nasal and tracheal caliber responses.
呼吸化学和反射干预已分别被证明会影响鼻阻力或气管张力。在本研究中，在麻醉、麻痹、人工通气（吸入氧气分数 = 100%）的猫身上同时监测鼻内径（通过恒定流量下的压力评估）和气管张力（通过分离气管段内充满液体的球囊压力评估）。我们研究了吸入二氧化碳、刺激坐骨神经以及将尼古丁（6×10⁻⁴摩尔/升）或利多卡因（2%溶液）应用于延髓腹侧表面（VMS）中间区域的效果。二氧化碳和VMS尼古丁分别导致气管压力显著升高[分别为147±73%和91±86%（标准差）]；鼻压力显著降低（分别为-35±10%和-20±13%）。相比之下，刺激坐骨神经导致气管压力（-50±36%）和鼻压力（-21±13%）均显著下降。将2%或4%的利多卡因应用于VMS可降低气管压力，但对鼻压力无显著影响。在VMS应用利多卡因后，鼻和气管对二氧化碳、坐骨神经刺激或VMS尼古丁（如果存在）的反应可忽略不计。这些结果表明VMS在调节和协调鼻和气管内径反应中起作用。
