Liquiritin apioside attenuates laryngeal chemoreflex but not mechanoreflex in rat pups.
Liquiritin apioside attenuates laryngeal chemoreflex but not mechanoreflex in rat pups.
复制标题
甘草苷芹菜苷可减弱大鼠幼仔的喉部化学反射，但不会减弱机械感受反射。
DOI：
10.1152/ajplung.00306.2019
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发表时间：
2020
期刊：
影响因子：
--
通讯作者：
Xu,Fadi
中科院分区：
文献类型：
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作者：
Wei,Wan;Gao,Xiuping;Zhao,Lei;Zhuang,Jianguo;Jiao,Yang;Xu,Fadi
甘草黄酮苷(LA)是甘草的主要黄酮类成分，据报道可通过作用于周围神经抑制吸入辣椒素(CAP；一种瞬时受体电位香草素1(TRPV1)的刺激剂)引起的清醒豚鼠咳嗽反应。然而，缺乏LA对呼吸道感觉纤维有直接影响的证据。考虑到喉化学感受器和机械感受器在触发呼吸暂停和咳嗽中的重要作用，我们研究了LA是否通过直接作用于喉上神经(SLN)来抑制对这些受体刺激的呼吸暂停反应。在麻醉大鼠幼鼠咽内给予化学刺激[CAP、HCl和蒸馏水(DW)]和机械刺激[空气脉冲(AP)]以诱发呼吸暂停。这些刺激在咽内LA治疗或SLN周围LA治疗后重复，以确定LA对SLN的直接影响。我们的结果显示，所有刺激都会立即引发呼吸暂停。咽内LA治疗可显著减轻对化学刺激的呼吸暂停反应，但不能减轻机械刺激的反应。周围SLN LA治疗后也观察到同样的衰减。由于喉C纤维的TRPV1受体参与了CAP诱发的呼吸暂停，因此随后采用膜片钳方法研究了LA对DII逆行示踪的喉C神经元活动的影响。La可显著改变CAP诱发的喉C神经元电流的电生理动力学，使其波幅降低，上升时间延长，衰减时间延长。综上所述，我们的结果首次揭示了LA通过直接作用于SLN(喉C纤维的TRPV1受体)来抑制喉化学受体介导的呼吸暂停。
Liquiritin apioside (LA), a main flavonoid component of licorice, reportedly suppresses cough responses to inhalation of aerosolized capsaicin [CAP; a stimulant to transient receptor potential vanilloid 1 (TRPV1)] in conscious guinea pigs via acting on peripheral nerves. However, the evidence of LA having a direct effect on airway sensory fibers is lacking. Considering the important role laryngeal chemoreceptors and mechanoreceptors play in triggering apnea and cough, we studied whether LA suppressed the apneic responses to stimulation of these receptors via directly acting on the superior laryngeal nerve (SLN). Intralaryngeal delivery of chemical [CAP, HCl, and distilled water (DW)] and mechanical [an air-pulse (AP)] stimulations was applied in anesthetized rat pups to evoke the apnea. These stimuli were repeated after intralaryngeal LA treatment or peri-SLN LA treatment to determine the direct effect of LA on the SLN. Our results showed that all stimuli triggered an immediate apnea. Intralaryngeal LA treatment significantly attenuated the apneic response to chemical but not mechanical stimulations. The same attenuation was observed after peri-SLN LA treatment. Owing that TRPV1 receptors of laryngeal C fibers are responsible for the CAP-triggered apneas, the LA impact on the activity of laryngeal C neurons retrogradely traced by DiI was subsequently studied using a patch-clamp approach. LA pretreatment significantly altered the electrophysiological kinetics of CAP-induced currents in laryngeal C neurons by reducing their amplitudes, increasing the rise times, and prolonging the decay times. In conclusion, our results, for the first time, reveal that LA suppresses the laryngeal chemoreceptor-mediated apnea by directly acting on the SLN (TRPV1 receptors of laryngeal C fibers).