School of Electrical and Computer Engineering, Purdue University, West Lafayette, IN, USA.
Purdue Institute for Integrative Neuroscience, Purdue University, West Lafayette, IN, USA.
Neurogastroenterol Motil. 2018 Oct;30(10):e13380. doi: 10.1111/nmo.13380. Epub 2018 May 24.
Vagus nerve stimulation (VNS) is an emerging electroceutical therapy for remedying gastric disorders that are poorly managed by pharmacological treatments and/or dietary changes. Such therapy seems promising as the vagovagal neurocircuitry modulates the enteric nervous system to influence gastric functions.
Here, the modulatory effects of left cervical VNS on gastric emptying in rats were quantified using a (i) feeding protocol in which the animal voluntarily consumed a postfast, gadolinium-labeled meal and (ii) a non-invasive imaging method to measure antral motility, pyloric activity and gastric emptying based on contrast-enhanced magnetic resonance imaging (MRI) and computer-assisted image processing pipelines.
Vagus nerve stimulation significantly accelerated gastric emptying (sham vs VNS: 29.1% ± 1.5% vs 40.7% ± 3.9% of meal emptied per 4 hours), caused a greater relaxation of the pyloric sphincter (sham vs VNS: 1.5 ± 0.1 vs 2.6 ± 0.4 mm cross-sectional area of lumen), and increased antral contraction amplitude (sham vs VNS: 23.3% ± 3.0% vs 32.5% ± 3.0% occlusion), peristaltic velocity (sham vs VNS: 0.50 ± 0.02 vs 0.67 ± 0.03 mm s ), but not its contraction frequency (sham vs VNS: 6.1 ± 0.2 vs 6.4 ± 0.2 contractions per minute, P = .22). The degree to which VNS relaxed the pylorus was positively correlated with gastric emptying rate (r = .5887, P < .001).
CONCLUSIONS & INFERENCES: The MRI protocol employed in this study is expected to enable advanced preclinical studies to understand stomach pathophysiology and its therapeutics. Results from this study suggest an electroceutical treatment approach for gastric emptying disorders using cervical VNS to control the degree of pyloric sphincter relaxation.
迷走神经刺激（VNS）是一种新兴的电疗方法，可治疗药物治疗和/或饮食改变效果不佳的胃部疾病。这种治疗方法似乎很有前途，因为迷走神经-迷走神经回路调节肠神经系统以影响胃功能。
在这里，使用（i）喂养方案和（ii）非侵入性成像方法来量化左侧颈 VNS 对大鼠胃排空的调节作用，在该方案中，动物自愿摄入餐后，钆标记餐，并基于对比增强磁共振成像（MRI）和计算机辅助图像处理管道测量胃窦动力、幽门活动和胃排空。
迷走神经刺激显著加速胃排空（假刺激与 VNS：4 小时内排空的餐量分别为 29.1%±1.5%和 40.7%±3.9%），使幽门括约肌更松弛（假刺激与 VNS：1.5±0.1 和 2.6±0.4 毫米横截面面积的管腔），并增加胃窦收缩幅度（假刺激与 VNS：23.3%±3.0%和 32.5%±3.0%闭塞）、蠕动速度（假刺激与 VNS：0.50±0.02 和 0.67±0.03 毫米/秒），但不影响其收缩频率（假刺激与 VNS：6.1±0.2 和 6.4±0.2 次/分钟，P=0.22）。VNS 放松幽门的程度与胃排空率呈正相关（r=0.5887，P<0.001）。
本研究中采用的 MRI 方案有望使先进的临床前研究能够了解胃的病理生理学及其治疗方法。本研究结果表明，使用颈 VNS 控制幽门括约肌松弛程度是治疗胃排空障碍的一种电疗方法。
