PDF(Pubmed)
Abstract：
Intravenous (systemic) bolus injection of fentanyl (FNT) reportedly induces an immediate vagal-mediated apnea; however, the precise origin of vagal afferents responsible for this apnea remains unknown. We tested whether intralaryngeal (local) application of FNT would also trigger an apnea and whether the apneic response to both local and systemic administration of FNT was laryngeal afferent-mediated. Cardiorespiratory responses to FNT were recorded in anesthetized male adult rats with and without bilateral sectioning of the superior laryngeal nerve (SLNx) or peri-SLN capsaicin treatment (SLNcap) to block local C-fiber signal conduction. Opioid mu-receptor (MOR)-immunoreactivity was detected in laryngeal C- and myelinated neurons. We found that local and systemic administration of FNT elicited an immediate apnea. SLNx, rather than SLNcap, abolished the apneic response to local FNT application though MORs were abundantly expressed in both laryngeal C- and myelinated neurons. Importantly, SLNx failed to affect the apneic response to systemic FNT administration. These results lead to the conclusion that laryngeal afferents\' MORs are responsible for the apneic response to local, but not systemic, administration of FNT.
摘要：
据报道，静脉（全身）推注芬太尼（FNT）可诱导立即迷走神经介导的呼吸暂停；然而，导致这种呼吸暂停的迷走神经传入的确切来源仍然未知。我们测试了FNT的咽内（局部）应用是否也会引发呼吸暂停，以及对FNT的局部和全身给药的呼吸暂停反应是否是喉传入介导的。在麻醉的雄性成年大鼠中记录对FNT的心脏呼吸反应，该大鼠有或没有双侧切除喉上神经（SLNx）或SLN辣椒素周围治疗（SLNcap）以阻断局部C纤维信号传导。在喉C-和有髓鞘神经元中检测到阿片类μ受体（MOR）免疫反应性。我们发现FNT的局部和全身给药引起立即的呼吸暂停。SLNx,而不是SLNcap，尽管MORs在喉C和有髓鞘神经元中均大量表达，但消除了对局部FNT应用的呼吸暂停反应。重要的是,SLNx未能影响对全身FNT给药的呼吸暂停反应。这些结果得出的结论是，喉传入MORs负责对局部呼吸的反应，但不是系统性的，管理FNT。
