Department of Otolaryngology - Head and Neck Surgery, University of Washington School of Medicine, Seattle, Washington, U.S.A.
Department of Otolaryngology - Head and Neck Surgery, Faculty of Medicine Suez Canal University, Ismailia, Egypt.
Laryngoscope. 2024 Dec;134(12):5028-5033. doi: 10.1002/lary.31675. Epub 2024 Aug 12.
Superior laryngeal nerve (SLN) function is critical to laryngeal sensation. Sensory dysfunction in the larynx, mediated through the internal branch of the superior laryngeal nerve (iSLN), is thought to occur with aging and neurodegenerative disease. However, objective analysis of iSLN neurophysiology is difficult due to its anatomic location and small diameter. This study measures sensory nerve action potentials (SNAP) from the iSLN in a rat model.
SNAP data were obtained from two adult rat strains (Sprague-Dawley, SD and Fischer 344 × Brown Norway F1 Hybrid rats, FBN). Evoked responses were obtained by stimulating the main trunk of the SLN and recording the response using a 160-μm cuff electrode placed around the iSLN. SNAP were averaged from 10 stimulations. Laryngeal adductor reflex (LAR) threshold measurements were obtained with stimulation of the iSLN and direct laryngoscopy. The sections of the iSLN were obtained for histologic analysis.
SLN-evoked responses were successfully obtained in 18 hemi-laryngeal preparations (SD n = 13 and FBN n = 5) with corresponding LAR threshold measurements. Mean(±SD) SNAP latency, total duration, amplitude, negative durations, and intensity were 2.28 ms (±0.56), 2.13 ms (±0.70), 879 μV (±535), and 0.69 mA (±0.25), respectively. SLN stimulation threshold to elicit an LAR was of 0.84 mA (±0.31).
It is feasible to record evoked SLN responses in two adult rat strains. This work may lead to a tractable animal model for objective measurements of SLN neurophysiology with various disease states.
NA Laryngoscope, 134:5028-5033, 2024.
喉上神经（SLN）的功能对喉感觉至关重要。通过喉上神经内支（iSLN）介导的感觉功能障碍被认为发生在衰老和神经退行性疾病中。然而，由于其解剖位置和小直径，对 iSLN 神经生理学的客观分析很困难。本研究在大鼠模型中测量了 iSLN 的感觉神经动作电位（SNAP）。
通过刺激 SLN 的主干并使用环绕 iSLN 的 160-μm 袖套电极记录响应，从两个成年大鼠品系（Sprague-Dawley，SD 和 Fischer 344×Brown Norway F1 杂种大鼠，FBN）获得 SNAP 数据。通过 10 次刺激平均 SNAP。通过刺激 iSLN 和直接喉镜获得喉内收反射（LAR）阈值测量。获得 iSLN 节段用于组织学分析。
在 18 个半喉准备中成功获得了 SLN 诱发反应（SD n=13，FBN n=5），并进行了相应的 LAR 阈值测量。平均（±SD）SNAP 潜伏期、总持续时间、幅度、负持续时间和强度分别为 2.28ms（±0.56）、2.13ms（±0.70）、879μV（±535）和 0.69mA（±0.25）。诱发 LAR 的 SLN 刺激阈值为 0.84mA（±0.31）。
在两种成年大鼠品系中记录诱发的 SLN 反应是可行的。这项工作可能为具有各种疾病状态的 SLN 神经生理学的客观测量提供一种可行的动物模型。
无 喉镜，134：5028-5033，2024。
