* Institute of Biomedical Engineering, Department of Electrical and Electronic Engineering, Imperial College London, SW7 2AZ, UK.
† Division of Diabetes, Endocrinology and Metabolism, Section of Endocrinology and Investigative Medicine, Imperial College London, W12 0NN, UK.
Int J Neural Syst. 2018 Nov;28(9):1850006. doi: 10.1142/S0129065718500065. Epub 2018 Feb 22.
Vagus Nerve Stimulation (VNS) has shown great promise as a potential therapy for a number of conditions, such as epilepsy, depression and for Neurometabolic Therapies, especially for treating obesity. The objective of this study was to characterize the left ventral subdiaphragmatic gastric trunk of vagus nerve (SubDiaGVN) and to analyze the influence of intravenous injection of gut hormone cholecystokinin octapeptide (CCK-8) on compound nerve action potential (CNAP) observed on the same branch, with the aim of understanding the impact of hormones on VNS and incorporating the methods and results into closed loop implant design.
The cervical region of the left vagus nerve (CerVN) of male Wistar rats was stimulated with electric current and the elicited CNAPs were recorded on the SubDiaGVN under four different conditions: Control (no injection), Saline, CCK1 (100[Formula: see text]pmol/kg) and CCK2 (1000[Formula: see text]pmol/kg) injections.
We identified the presence of A[Formula: see text], B, C1, C2, C3 and C4 fibers with their respective velocity ranges. Intravenous administration of CCK in vivo results in selective, statistically significant reduction of CNAP components originating from A and B fibers, but with no discernible effect on the C fibers in [Formula: see text] animals. The affected CNAP components exhibit statistically significant ([Formula: see text] and [Formula: see text]) higher normalized stimulation thresholds.
This approach of characterizing the vagus nerve can be used in closed loop systems to determine when to initiate VNS and also to tune the stimulation dose, which is patient-specific and changes over time.
迷走神经刺激（VNS）已显示出作为多种疾病（如癫痫、抑郁症）的潜在治疗方法的巨大潜力，并且对神经代谢治疗，特别是肥胖症的治疗也有一定作用。本研究的目的是描述左侧腹下迷走神经主干(subdiaphragmatic gastric trunk of vagus nerve, SubDiaGVN)的特征，并分析静脉内注射肠激素胆囊收缩素八肽(cholecystokinin octapeptide, CCK-8)对同一分支上观察到的复合神经动作电位(compound nerve action potential, CNAP)的影响，旨在了解激素对 VNS 的影响，并将方法和结果纳入闭环植入物设计中。
用电流刺激雄性 Wistar 大鼠左侧颈迷走神经(cervical region of the left vagus nerve, CerVN)，在四种不同条件下记录 SubDiaGVN 上诱发出的 CNAP：对照（无注射）、生理盐水、CCK1（100[Formula: see text]pmol/kg）和 CCK2（1000[Formula: see text]pmol/kg）注射。
我们鉴定了存在 A[Formula: see text]、B、C1、C2、C3 和 C4 纤维及其各自的速度范围。体内静脉注射 CCK 导致源自 A 和 B 纤维的 CNAP 成分选择性、统计学显著降低，但对[Formula: see text]动物的 C 纤维无明显影响。受影响的 CNAP 成分表现出统计学上显著的（[Formula: see text]和[Formula: see text]）更高的归一化刺激阈值。
这种描述迷走神经的方法可用于闭环系统中，以确定何时开始 VNS，还可以调整刺激剂量，刺激剂量是针对患者的，并且随时间变化。
