title: Effects of Nardostachys chinensis on spontaneous ventricular arrhythmias in rats with acute myocardial infarction.
abstract: OBJECTIVE
  To investigate the effects and mechanisms of Nardostachys chinensis (NC) on spontaneous ventricular arrhythmias in rats with hyper-acute myocardial infarction (AMI).
  
  
  METHODS
  Seventy-two rats were randomly divided into the control group (n = 24), metoprolol group (n = 24), and the NC group (n = 24). Premature ventricular contractions (PVCs), ventricular tachycardias (VTs), ventricular fibrillations (VFs), and blood pressure were monitored for 4 hours after coronary artery ligation. The connexin 43 (Cx43) expression in ventricular myocardium was measured by immunohistochemistry, Western blot, and real-time RT-PCR.
  
  
  RESULTS
  Compared with the control, metoprolol and NC decreased the VF incidence (50% vs. 4.2%, P < 0.001, and 50% vs. 12.5%, P = 0.005, respectively). There was a steady decrease in the cumulative number of PVCs and VTs within 4 hours from ligating in 3 groups. Compared with the control, metoprolol and NC reduced the cumulative number of VTs and PVCs. Compared with control, metoprolol and NC decreased the infarct size of the left ventricular tissue (55.98% ± 6.20% vs. 39.13% ± 4.53%, P < 0.001, and 55.98% ± 6.20% vs. 42.39% ± 3.44%, P < 0.001, respectively). The results from immunohistochemistry, Western blot, and real-time RT-PCR showed that the protein expression of Cx43 in the control group was significantly lower than that in the metoprolol and NC groups in the infarcted zone.
  
  
  CONCLUSIONS
  NC decreased the incidence of spontaneous ventricular arrhythmias (especially VF), reduced Cx43 degradation, and improved Cx43 redistribution in myocardial infarcted zone in rats with hyper-AMI. The data of the present study indicated that NC may be a promising drug in the future to prevent patients with AMI from lethal ventricular arrhythmias in prehospital setting.
authors.affiliation: *Department of Cardiovascular Medicine, The First Affiliated Hospital, and the Key Laboratory of Assisted Circulation, Ministry of Health, Sun Yat-Sen University, Guangzhou, China; and †Department of Ultrasonography, The First Affiliated Hospital, Sun Yat-Sen University, Guangzhou, China.
authors.forename: Jing
authors.initials: J
authors.lastname: Zhang
authors.forename: Can-Can
authors.initials: CC
authors.lastname: Qiang
authors.forename: Wei-Jie
authors.initials: WJ
authors.lastname: Li
authors.forename: Li-Juan
authors.initials: LJ
authors.lastname: Liu
authors.forename: Xiao-Xiong
authors.initials: XX
authors.lastname: Lin
authors.forename: Yun-Jiu
authors.initials: YJ
authors.lastname: Cheng
authors.forename: Kai
authors.initials: K
authors.lastname: Tang
authors.forename: Feng-Juan
authors.initials: FJ
authors.lastname: Yao
authors.forename: Su-Hua
authors.initials: SH
authors.lastname: Wu
mesh_terms: D000818:Animals; D000889:Anti-Arrhythmia Agents / Q000008:administration & dosage / Q000627:therapeutic use*; D001794:Blood Pressure / Q000187:drug effects; D015153:Blotting, Western; D018031:Connexin 43 / Q000378:metabolism; D004365:Drugs, Chinese Herbal / Q000008:administration & dosage / Q000627:therapeutic use*; D004562:Electrocardiography; D005260:Female; D007150:Immunohistochemistry; D008297:Male; D008790:Metoprolol / Q000008:administration & dosage / Q000627:therapeutic use; D009203:Myocardial Infarction / Q000150:complications / Q000188:drug therapy* / Q000378:metabolism / Q000473:pathology; D032404:Nardostachys / Q000737:chemistry*; D017207:Rats, Sprague-Dawley; D060888:Real-Time Polymerase Chain Reaction; D027343:Rhizome / Q000737:chemistry; D017180:Tachycardia, Ventricular / Q000209:etiology / Q000378:metabolism / Q000473:pathology / Q000517:prevention & control*; D014693:Ventricular Fibrillation / Q000209:etiology / Q000378:metabolism / Q000473:pathology / Q000517:prevention & control*; D018879:Ventricular Premature Complexes / Q000209:etiology / Q000378:metabolism / Q000473:pathology / Q000517:prevention & control*
chemical_list: D000889:Anti-Arrhythmia Agents; D018031:Connexin 43; D004365:Drugs, Chinese Herbal; C580592:Gja1 protein, rat; D008790:Metoprolol