title: Effect of imidapril on heterogeneity of slow component of delayed rectifying K+ current in rabbit left ventricular hypertrophic myocytes.
abstract: OBJECTIVE
  To investigate the transmural heterogeneous change of slow component of delayed rectifying potassium current in rabbit left ventricular hypertrophic myocytes and the effect of long-term treatment with imidapril (Imi).
  
  
  METHODS
  Rabbits were divided into hypertrophy group (left ventricular hypertrophy induced by partial ligation of abdominal aorta), Imi-treated group (surgical treatment as hypertrophy group was treated with Imi), and Sham-operated group as control. Whole-cell patch-clamp technique was used to record potassium currents.
  
  
  RESULTS
  (1) Membrane capacitance was larger in hypertrophic cells than in sham-operated and Imi-treated cells. Action potential durations (APD) of epicardium (Epi), midmyocardium (M), and endocardium (Endo) were remarkably longer in hypertrophic cells than those in Imi-treated and sham-operated cells. The prolongation of APD90 of M was the most pronounced in three layer myocytes of hypertrophic group. (2) The densities of I(Ks,tail) of hypertrophic cells were reduced by Epi 25.3 %+/-2.9 %, M 38.0 %+/-3.7 % and Endo 20.3 %+/-4.7 % compared with those of sham-operated cells. The decrease of IKs,tail density was more pronounced in M than in Epi and Endo (n = 13, P<0.01 vs Epi or Endo). (3) The density of I(Kr,tail) in Imi-treated cells was not different from that in sham-operated cells significantly (n=10).
  
  
  CONCLUSIONS
  Imi reduced prolongation of APD and inhibited the heterogeneous change of I(Ks,tail) in rabbit left ventricular hypertrophic myocytes.
authors.affiliation: Department of Cardiology, Tongji Hospital Affiliated to Tongji Medical College, Huazhong Science and Technology University, Wuhan 430030, China. liyang40@hotmail.com
authors.forename: Yang
authors.initials: Y
authors.lastname: Li
authors.forename: Zai-Ying
authors.initials: ZY
authors.lastname: Lu
authors.forename: Jian-Men
authors.initials: JM
authors.lastname: Xiao
authors.forename: Jie
authors.initials: J
authors.lastname: Ma
authors.forename: Hui-Yan
authors.initials: HY
authors.lastname: Niu
authors.forename: Nian
authors.initials: N
authors.lastname: Liu
authors.forename: Yan-Fei
authors.initials: YF
authors.lastname: Ruan
mesh_terms: D000200:Action Potentials / Q000187:drug effects; D000806:Angiotensin-Converting Enzyme Inhibitors / Q000494:pharmacology; D000818:Animals; D005260:Female; D017379:Hypertrophy, Left Ventricular / Q000473:pathology*; D007093:Imidazoles / Q000494:pharmacology*; D048289:Imidazolidines; D008297:Male; D032383:Myocytes, Cardiac / Q000187:drug effects; D015221:Potassium Channels / Q000378:metabolism*; D024642:Potassium Channels, Voltage-Gated; D011817:Rabbits
chemical_list: D000806:Angiotensin-Converting Enzyme Inhibitors; D007093:Imidazoles; D048289:Imidazolidines; D015221:Potassium Channels; D024642:Potassium Channels, Voltage-Gated; C059983:potassium channel protein I(sk); C065166:imidapril