title: Sleep-related changes in cardiovascular autonomic regulation in left coronary artery ligation rats: Neural mechanism facilitating arrhythmia after myocardial infarction.
abstract: BACKGROUND
  Autonomic imbalance with increased sympathetic and decreased parasympathetic activities is observed in patients after myocardial infarction (MI). We aimed to investigate sleep-related changed in autonomic regulation in left coronary artery (LCA) ligation rats.
  
  
  METHODS
  Wireless transmission of polysomnographic recording was performed in sham and LCA ligation male rats during normal daytime sleep with and without atenolol treatment. Spectral analyses of the electroencephalogram (EEG) and electromyogram (EMG) were evaluated to define active waking (AW), quiet and paradoxical sleeps (QS, PS). Cardiac autonomic activities were measured by analyzing the power spectrum of heart rate variability (HRV). EEG, EMG and HRV were recorded over 6h for consecutive 3days in all groups.
  
  
  RESULTS
  In LCA ligation group, there were higher LF and LF/HF ratio on QS phase, but not AW and PS phases, compared to atenolol treated sham and LCA ligation groups, respectively. The HF component was not significantly changed on all groups in both sleep and awake phases. Sleep interruption was more frequent in LCA ligation rats compared to sham, and it was not found in LCA ligation with atenolol treatment group. Increased AW, PS and decreased QS time were noted in LCA ligation group, compared to sham and it was restored to baseline in LCA ligation with atenolol treatment group.
  
  
  CONCLUSIONS
  Our results demonstrate significant sleep fragmentations with sympathetic hyperactivity during QS stages after MI, and atenolol could restore the autonomic dysfunction and sleep disturbance. The finding explains the cause of sleep-related fetal arrhythmia and sudden cardiac death after MI.
authors.affiliation: Division of Cardiology, Taipei Veterans General Hospital, Taipei, Taiwan; Institute of Clinical Medicine, and Cardiovascular Research Institute, National Yang-Ming University, Taipei, Taiwan.
authors.forename: Wei-Lun
authors.initials: WL
authors.lastname: Lin
authors.affiliation: Division of Cardiology, Taipei Veterans General Hospital, Taipei, Taiwan; Institute of Clinical Medicine, and Cardiovascular Research Institute, National Yang-Ming University, Taipei, Taiwan. Electronic address: gyrus@ms65.hinet.net.
authors.forename: Li-Wei
authors.initials: LW
authors.lastname: Lo
authors.affiliation: Institute of Brain Science, National Yang-Ming University, Taipei, Taiwan; Taipei Fuhsing Private School, Taipei, Taiwan.
authors.forename: Hau-Ruey
authors.initials: HR
authors.lastname: Chen
authors.affiliation: Institute of Brain Science, National Yang-Ming University, Taipei, Taiwan.
authors.forename: Chun-Ting
authors.initials: CT
authors.lastname: Lai
authors.affiliation: Division of Cardiology, Taipei Veterans General Hospital, Taipei, Taiwan.
authors.forename: Shinya
authors.initials: S
authors.lastname: Yamada
authors.affiliation: Division of Cardiology, Taipei Veterans General Hospital, Taipei, Taiwan.
authors.forename: Shin-Huei
authors.initials: SH
authors.lastname: Liu
authors.affiliation: Division of Cardiology, Taipei Veterans General Hospital, Taipei, Taiwan.
authors.forename: Yu-Hui
authors.initials: YH
authors.lastname: Chou
authors.affiliation: Division of Cardiology, Taipei Veterans General Hospital, Taipei, Taiwan; Institute of Clinical Medicine, and Cardiovascular Research Institute, National Yang-Ming University, Taipei, Taiwan.
authors.forename: Shih-Ann
authors.initials: SA
authors.lastname: Chen
authors.affiliation: Institute of Clinical Medicine, and Cardiovascular Research Institute, National Yang-Ming University, Taipei, Taiwan; Division of Cardiology, Taichung Veterans General Hospital, Taipei, Taiwan.
authors.forename: Yun-Ching
authors.initials: YC
authors.lastname: Fu
authors.affiliation: Institute of Brain Science, National Yang-Ming University, Taipei, Taiwan. Electronic address: tbjkuo@ym.edu.tw.
authors.forename: Terry B J
authors.initials: TB
authors.lastname: Kuo
mesh_terms: D000818:Animals; D001145:Arrhythmias, Cardiac / Q000175:diagnosis / Q000209:etiology / Q000503:physiopathology*; D001341:Autonomic Nervous System / Q000503:physiopathology; D003331:Coronary Vessels / Q000503:physiopathology*; D004562:Electrocardiography / Q000379:methods; D004569:Electroencephalography / Q000379:methods; D006339:Heart Rate / Q000502:physiology*; D008026:Ligation; D008297:Male; D009203:Myocardial Infarction / Q000150:complications / Q000175:diagnosis / Q000503:physiopathology*; D017286:Polysomnography / Q000379:methods; D051381:Rats; D011921:Rats, Inbred WKY; D012890:Sleep / Q000502:physiology*; D012893:Sleep Wake Disorders / Q000175:diagnosis / Q000503:physiopathology*
keywords: Autonomic; Heart rate variability; Myocardial infarction; Sleep