Stumpp Lars, Smets Hugo, Vespa Simone, Cury Joaquin, Doguet Pascal, Delbeke Jean, Hermans Emmanuel, Sevcencu Christian, Nielsen Thomas N, Nonclercq Antoine, Tahry Riem El
Institute of Neuroscience, Université Catholique de Louvain, Belgium.
BEAMS Department, Université libre de Bruxelles, Belgium.
J Neurosci Methods. 2020 Sep 1;343:108832. doi: 10.1016/j.jneumeth.2020.108832. Epub 2020 Jun 30.
Vagus nerve stimulation is a treatment for refractory epilepsy. The vagus nerve carries parasympathetic information and innervates multiple organs. As seizures are commonly associated with autonomic manifestations, we believe that biomarkers for diseases affecting autonomic functions such as epilepsy can be found in vagus nerve signals.
We present a method to record vagus nerve electroneurogram (VENG) and detect in the VENG single unit activity in anesthetized rats during Pentylenetetrazol induced seizures using a true tripolar cuff electrode.
The VENG consisted of high amplitude bursts and lower amplitude bursts synchronous to respiration and heartbeat respectively. The average spikes exhibited a triphasic shape with duration below 1.5ms and root mean square amplitude varied between 5.5 +/- 0.2 μV and 11.4 +/- 3.1 μV depending on the type of recording. An increase of the contact distance resulted in a signal amplitude increase. Application of Lidocaine led to a total disappearance of the recorded spontaneous spiking of the nerve.
True tripolar cuff electrodes exhibited a better performance in terms of artefact rejection, stability and reproducibility of the signal compared to commonly used hook electrodes which is of special interest in seizures where important motion and EMG artifacts are expected.
We present a new method to record single unit activity of the vagus nerve during acute chemically induced seizures in rats and verified the neural origin of the recorded signals. This recording method might be a powerful tool to develop seizure biomarkers based on VENG.
迷走神经刺激是治疗难治性癫痫的一种方法。迷走神经传递副交感神经信息并支配多个器官。由于癫痫发作通常与自主神经表现相关，我们认为在迷走神经信号中可以找到影响自主神经功能的疾病（如癫痫）的生物标志物。
我们提出了一种使用真正的三极袖带电极记录麻醉大鼠在戊四氮诱导癫痫发作期间迷走神经电图（VENG）并检测VENG中单个单位活动的方法。
VENG由分别与呼吸和心跳同步的高振幅猝发和低振幅猝发组成。平均尖峰呈现三相形状，持续时间低于1.5毫秒，均方根振幅根据记录类型在5.5±0.2微伏和11.4±3.1微伏之间变化。接触距离增加导致信号幅度增加。利多卡因的应用导致记录的神经自发放电完全消失。
与常用的钩状电极相比，真正的三极袖带电极在伪迹抑制、信号稳定性和可重复性方面表现更好，这在预期会出现重要运动和肌电图伪迹的癫痫发作中尤为重要。
我们提出了一种在大鼠急性化学诱导癫痫发作期间记录迷走神经单个单位活动的新方法，并验证了记录信号的神经起源。这种记录方法可能是基于VENG开发癫痫生物标志物的有力工具。
