Effects of valsartan on L-type calcium current in ventricular myocytes of rabbits after myocardial infarction
10.3760/cma.j.issn.1671-0282.2010.09.011
- VernacularTitle:兔心肌梗死后口服缬沙坦对室性心律失常的影响
- Author:
Ya ZHONG
;
Congxin HUANG
;
Qingyan ZHAO
;
Teng WANG
;
Feng CAO
- Publication Type:Journal Article
- Keywords:
Myocardial infarction;
Ventricular arrhythmias;
L-type calcium current;
Patch clamp;
Valsartan;
Rabbit
- From:
Chinese Journal of Emergency Medicine
2010;19(9):949-952
- CountryChina
- Language:Chinese
-
Abstract:
Objective To determine the effects of valsartan, a specific angiotensin Ⅱ type 1 receptor blockade, on arrhythmia in rabbits after myocardial infarction and to discuss the mechanism. Method Twentyfour rabbits were randomly (random number) divided into sham operated (SO) group ( n = 8), myocardial infarction (MI) group ( n = 8) and valsartan (VAL) group ( n = 8). The rabbits of SO group were operated upon with median stemotomy without left ventricular coronary artery hgature. The rabbits of MI group and VAL group had median stemotomy with left ventricular coronary artery ligature. After MI, the rabbits of VAL group were fed with border zone of infracted left ventricular wall and the L-type calcium current was recorded by whole-cell patch clamp technique. Results Ventricular tachycardia or fibrillation (VT/VF) episodes were markedly decreased in VAL group than that in MI group [(3.2 ± 0. 6) vs. ( 11.7 ± 1.8)] after 12 weeks. The density of Ica-L current was higher in MI group than that in SO group and VAL group [( - 9.12 ± 0.73) pA/pF vs. ( - 6.29 ± 0.65) pA/pF and ( - 6.75 ± 0.64) pA/pF], ( P ＜ 0.05), however, there were no significant differences in Ica-L current between So group and VAL group ( P ＞ 0.05). Conclusions Valsartan reduces the VT/VF episodes in rabbits after MI. The effects of valsartan may be attributed to the inhibited electrical remodeling after MI.
