title: The Use of Noninvasive Vagal Nerve Stimulation to Inhibit Sympathetically Induced Sinus Node Acceleration: A Potential Therapeutic Approach for Inappropriate Sinus Tachycardia.
abstract: BACKGROUND
  Hyperactivity of the cardiac sympathetic nervous system may underlie the pathogenesis of inappropriate sinus tachycardia (IST). Studies have proven that cervical vagal stimulation could inhibit stellate ganglion neural activity.
  
  
  METHODS
  To investigate whether noninvasive vagal nerve stimulation (NVNS) could inhibit sympathetically induced sinus node acceleration by reducing right stellate ganglion (RSG) neural activity.
  
  
  METHODS
  Sixteen anesthetized dogs were randomly divided into NVNS group (with NVNS, n = 8) and control group (with sham NVNS, n = 8). NVNS was delivered to the vagus nerve innervating at the right tragus with a voltage of 80% below the threshold, the minimal voltage to slow the sinus rate or atrioventricular conduction. The maximal sinus rate accelerations induced by high-frequency stimulation (HFS) of RSG and RSG neural activity were measured at baseline and 3 hours after NVNS. At the end, SK2, c-fos, and NGF protein expression in RSG were examined in both groups.
  
  
  RESULTS
  Compared to baseline, the maximal sinus node acceleration induced by RSG stimulation and the RSG neural activity were both significantly attenuated after 3 hours of NVNS (P < 0.05 for both). However, these indices did not change significantly in the control group (P > 0.05). SK2 expression in RSG was significantly higher and c-fos and NGF expressions were significantly lower in the NVNS group than those in the control group (P < 0.05).
  
  
  CONCLUSIONS
  Noninvasive vagal nerve stimulation may suppress RSG activity possibly by modulating SK2, c-fos, and NGF expressions in RSG, thus inhibiting sympathetically induced sinus node acceleration.
authors.affiliation: Department of Cardiology, Renmin Hospital of Wuhan University, Cardiovascular Research Institute of Wuhan University, Wuhan, Hubei, China.
authors.forename: Xiaoya
authors.initials: X
authors.lastname: Zhou
authors.affiliation: Department of Cardiology, Renmin Hospital of Wuhan University, Cardiovascular Research Institute of Wuhan University, Wuhan, Hubei, China.
authors.forename: Liping
authors.initials: L
authors.lastname: Zhou
authors.affiliation: Department of Cardiology, Renmin Hospital of Wuhan University, Cardiovascular Research Institute of Wuhan University, Wuhan, Hubei, China.
authors.forename: Songyun
authors.initials: S
authors.lastname: Wang
authors.affiliation: Department of Cardiology, Renmin Hospital of Wuhan University, Cardiovascular Research Institute of Wuhan University, Wuhan, Hubei, China.
authors.forename: Lilei
authors.initials: L
authors.lastname: Yu
authors.affiliation: Department of Cardiology, Renmin Hospital of Wuhan University, Cardiovascular Research Institute of Wuhan University, Wuhan, Hubei, China.
authors.forename: Zhuo
authors.initials: Z
authors.lastname: Wang
authors.affiliation: Department of Cardiology, Renmin Hospital of Wuhan University, Cardiovascular Research Institute of Wuhan University, Wuhan, Hubei, China.
authors.forename: Bing
authors.initials: B
authors.lastname: Huang
authors.affiliation: Department of Cardiology, the Second Xiangya Hospital of Central South, University, Changsha, Hunan, China.
authors.forename: Mingxian
authors.initials: M
authors.lastname: Chen
authors.affiliation: Department of Cardiology, Renmin Hospital of Wuhan University, Cardiovascular Research Institute of Wuhan University, Wuhan, Hubei, China.
authors.forename: Jun
authors.initials: J
authors.lastname: Wan
authors.affiliation: Department of Cardiology, Renmin Hospital of Wuhan University, Cardiovascular Research Institute of Wuhan University, Wuhan, Hubei, China.
authors.forename: Hong
authors.initials: H
authors.lastname: Jiang
mesh_terms: D000818:Animals; D004195:Disease Models, Animal; D004285:Dogs; D006339:Heart Rate; D020932:Nerve Growth Factor / Q000235:genetics / Q000378:metabolism; D016760:Proto-Oncogene Proteins c-fos / Q000235:genetics / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D012849:Sinoatrial Node / Q000294:innervation*; D051640:Small-Conductance Calcium-Activated Potassium Channels / Q000235:genetics / Q000378:metabolism; D013233:Stellate Ganglion / Q000378:metabolism / Q000503:physiopathology*; D013616:Tachycardia, Sinus / Q000209:etiology / Q000235:genetics / Q000378:metabolism / Q000503:physiopathology / Q000628:therapy*; D013997:Time Factors; D055536:Vagus Nerve Stimulation / Q000379:methods*
chemical_list: D016760:Proto-Oncogene Proteins c-fos; D012333:RNA, Messenger; D051640:Small-Conductance Calcium-Activated Potassium Channels; D020932:Nerve Growth Factor
keywords: autonomic nervous system; inappropriate sinus tachycardia; noninvasive vagal nerve stimulation; parasympathetic nervous system; right stellate ganglion