豚鼠对脉冲性耳间振动的椭圆囊复合动作电位阈值，以及小鼠、大鼠、绵羊和人类的机械调谐曲线估计
Utricular Compound Action Potential Thresholds to Pulsed Interaural Vibration in Guinea Pig, and Mechanical Tuning Curve Estimates in Mouse, Rat, Sheep, and Human.
文献信息
| PMID | 42745105 |
|---|---|
| 原文 | 在 PubMed 查看原文 ↗ |
| 发表日期 | 2026 |
| 作者 | Richard D Rabbitt |
| 作者单位 | Biomedical Engineering, Otolaryngology and Neuroscience Program, University of Utah, Salt Lake City, UT, 84112, USA. r.rabbitt@utah.edu. |
| 期刊 | Journal of the Association for Research in Otolaryngology : JARO |
| SCI 分区 | Q1 |
| IF | 3.1 |
| 研究类型 | 基础研究 · 基础／转化 |
| 所属专科 | 耳科 |
中文摘要
目的： 确定由脉冲性耳间骨传导振动（BCV）诱发的 vestibular 复合动作电位（vCAPs）的阈值，并估计多种哺乳动物中正弦 BCV 和镫骨振动（SV）的同步调谐曲线。
方法： 阈值根据先前报道的 vCAP 数据确定，这些数据来自对雌雄豚鼠施加的振动脉冲，其加速度幅度范围约为 0.0003 至 0.04 m s-2（约 0.3-4 mG），上升时间约为 0.17 至 0.6 ms。应用一个简单的二自由度模型来估计构成频率依赖性同步基础的机械调谐曲线。
结果： 刺激诱发的 vCAPs 在 dB 尺度上随峰值加速度线性增加，并在同步阈值 -54 dB（re: 1 m s-2）处截距为零。将阈值与模型结合预测，耳石与感觉上皮之间的临界剪切率为 -34 dB（re: 1 rad s-1）足以诱发同步动作电位。达到临界剪切率所需的耳间加速度阈值预测，正弦 BCV 的调谐曲线呈 V 形，在所评估的各物种中阈值接近 -55 dB（re: 1 m s-2）。特征频率（CF）估计为：人类 210 Hz，绵羊 286 Hz，豚鼠 526 Hz，大鼠 600 Hz，小鼠 688 Hz。SV 的估计阈值为 -50 dB（re: 1 m s⁻2），调谐相对宽泛，约延伸至 BCV CF 以上 1 kHz。
结论： 结果与以下假说一致：椭圆囊神经中的同步动作电位由作用于感觉毛束的机械剪切率驱动。
英文摘要
PURPOSE: Determine thresholds of vestibular compound action potentials (vCAPs) evoked by pulsed interaural bone-conducted vibration (BCV) and estimate synchronization tuning curves for sinusoidal BCV and stapes vibration (SV) in multiple mammalian species.
METHODS: Thresholds were determined from previously reported vCAP data in response to vibration pulses with acceleration amplitudes ranging from ~ 0.0003 to 0.04 m s-2 (~ 0.3-4 mG) and rise times from ~ 0.17 to 0.6 ms in guinea pigs of either sex. A simple two-degrees-of-freedom model was applied to estimate mechanical tuning curves underlying frequency-dependent synchronization.
RESULTS: Stimulus-evoked vCAPs increased linearly with peak acceleration on a dB scale, and intercepted zero at a synchronization threshold of -54 dB (re: 1 m s-2). Combining the threshold with the model predicts a critical shear rate of - 34 dB (re: 1 rad s-1) between otoconia and the sensory epithelium is sufficient to evoke synchronized action potentials. The interaural acceleration threshold required to reach the critical shear rate predicts a V-shaped tuning curve for sinusoidal BCV with thresholds near -55 dB (re: 1 m s-2) across species evaluated. The characteristic frequency (CF) was estimated as 210 Hz for humans, 286 Hz for sheep, 526 Hz for guinea pigs, 600 Hz for rats, and 688 Hz for mice. The threshold estimated for SV was - 50 dB (re: 1 m s⁻2) with relatively broad tuning extending approximately 1 kHz above the BCV CF.
CONCLUSION: Results are consistent with the hypothesis that synchronized action potentials in the utricular nerve are driven by the mechanical shear rate acting on sensory hair bundles.