Tougas G, Hudoba P, Fitzpatrick D, Hunt R H, Upton A R
Department of Medicine, McMaster University, Hamilton, Ontario, Canada.
Am J Physiol. 1993 Mar;264(3 Pt 1):G486-91. doi: 10.1152/ajpgi.1993.264.3.G486.
Cerebral evoked responses following direct electrical stimulation of the vagus and esophagus were compared in 8 epileptic subjects and with those recorded after esophageal stimulation in 12 healthy nonepileptic controls. Direct vagal stimulation was performed using a left cervical vagal pacemaker, which is used in the treatment of epilepsy. Esophageal stimulation was obtained with the use of an esophageal assembly incorporating two electrodes positioned 5 and 20 cm orad to the lower esophageal sphincter. Evoked potential responses were recorded with the use of 20 scalp electrodes. The evoked potential responses consisted of three distinct negative peaks and were similar with the use of either vagal or esophageal stimulation. The measured conduction velocity of the afferent response was 7.5 m/s in epileptic subjects and 10 m/s in healthy controls, suggesting that afferent conduction is through A delta-fibers rather than slower C afferent fibers. We conclude that the cortical-evoked potential responses following esophageal electrical stimulation are comparable to direct electrical stimulation of the vagus nerve and involve mostly A delta-fibers. This approach provides a method for the assessment of vagal afferent gastrointestinal sensory pathways in health and disease.
在8名癫痫患者中比较了直接电刺激迷走神经和食管后诱发的脑反应，并与12名健康非癫痫对照者食管刺激后记录的反应进行了比较。使用用于癫痫治疗的左颈迷走神经起搏器进行直接迷走神经刺激。使用包含两个位于食管下括约肌口侧5厘米和20厘米处的电极的食管组件进行食管刺激。使用20个头皮电极记录诱发电位反应。诱发电位反应由三个不同的负峰组成，迷走神经或食管刺激时相似。癫痫患者传入反应的测量传导速度为7.5米/秒，健康对照者为10米/秒，表明传入传导是通过Aδ纤维而不是较慢的C传入纤维。我们得出结论，食管电刺激后皮层诱发电位反应与迷走神经直接电刺激相当，并且主要涉及Aδ纤维。这种方法为评估健康和疾病状态下迷走神经传入性胃肠感觉通路提供了一种手段。
