title: [Alterations of after depolarization and triggered activity in myocardiac muscle during progression of mouse aortic stenosis].
abstract: OBJECTIVE
  To explore the alterations of after depolarization and triggered activity in myocardiac muscle during progression of mouse aortic stenosis.
  
  
  METHODS
  After the establishment of mouse aortic stenosis model, the heart was collected and intracellular potential was recorded using standard glass microelectrode. After the recording, the action potential (AP), early after depolarization (EAD), delayed after depolarization (DAD) in papillary muscles were analysed.
  
  
  RESULTS
  (1) Compared with that of time-matched control mice, there were no changes of the action potoutial duration at 90% repolarization(APD90) in model mice at 2 and 5 weeks, whereas the APD90 was progressively prolonged at 9 and 13 weeks. (2) During the 30 minites of the experiment, spontaneous EADs and DADs were frequently present in medel mice at 9 and 13 weeks, were not in control and model mice at 2 and 5 weeks. (3) Compared with those of control group, EADs and DADs triggered by hypokalaemia or isoproterenol were increased significantly. The incidence rate of triggering EADs and DADs was progressively increased over time.
  
  
  CONCLUSIONS
  EAD, DAD and trigger activities increase gradually during the process of aortic stenosis, and it suggests that the myocardium electrical-instability is markedly increased in the insult hearts.
authors.forename: Hong
authors.initials: H
authors.lastname: Jiao
authors.forename: Yong
authors.initials: Y
authors.lastname: Zhang
authors.forename: Xiao-Ling
authors.initials: XL
authors.lastname: Wang
mesh_terms: D000200:Action Potentials / Q000502:physiology*; D000818:Animals; D001024:Aortic Valve Stenosis / Q000503:physiopathology*; D004195:Disease Models, Animal; D008297:Male; D051379:Mice; D032383:Myocytes, Cardiac / Q000502:physiology*