摘要
目的观察容量负荷联合压力超负荷心力衰竭兔左房心肌细胞K+通道mRNA水平的变化,并探讨贝那普利对心房肌细胞K+通道mRNA水平的影响。方法实验分为3组:假手术组(SO,n=10),心力衰竭组(HF,n=15),贝那普利干预组(BHF,n=13)。用容量负荷联合压力超负荷诱导形成心力衰竭兔模型;用超声心动指标、心体比、脑钠肽(BNP)评价心衰模型;用real-time PCR法测定瞬时外向钾电流(Ito)、快激活延迟整流钾电流(IKr)、慢激活延迟整流钾电流(IKs)、内向整流钾电流(IK1)亚基的mRNA水平。结果 1与假手术组相比,心衰组兔超声心动指标显示左房、左室增大,心脏收缩功能、舒张功能明显减低(P<0.01);血清BNP水平明显升高(P<0.01);心体比明显增大(P<0.01)。2与心衰组比较,贝那普利组干预6周提高了心衰兔的心功能,使BNP下降,扩大的左室和左房明显回缩。3与假手术组比较,心衰组左房心肌细胞Kv4.3和Kv1.4(均编码Ito的α亚基)mRNA水平下降了59%(P<0.01)和47%(P<0.01);Kv LQT1(编码IKs的α亚基)和min K(编码IKs的β亚基)的mRNA水平分别下降了29%(P<0.01)和32%(P<0.01);Kir2.1(编码IK1的α亚基)的mRNA水平降低了22%(P<0.01)。4贝那普利干预6周后,与心衰组比,Kv4.3、Kv LQT1和min K的mRNA水平上调了29%(P<0.01)、18%(P<0.01)和14%(P<0.01);Kv1.4和Kir2.1的mRNA水平没有明显变化(P>0.05)。5ERG(编码IKr的α亚基)的mRNA水平在三组兔中无变化。结论心力衰竭兔左房扩大,Kv4.3、Kv1.4、Kv LQT1、min K和Kir2.1的mRNA水平明显下降,ERG mRNA水平不变。贝那普利干预后心衰兔左房、左室缩小并部分逆转Kv4.3、Kv LQT1、min K mRNA水平的下调。
Objective To observe the changes of potassium channels mRNA level in atrial myocytes of heart failure rabbits induced by volume overload combined with pressure overload,and to explore the effects of benapril on potassium channels mRNA level.Methods New Zealand rabbits were randomized into 3 groups：sham operation group （SO,n =10）,heart failure group （HF,n =15）,heart failure ＋ benapril intervention group（BHF,n =13）.Heart failure rabbits were induced by volume overload combined with pressure overload.Echocardiographic variables and plasma brain natriuretic peptide（BNP）level were determined to evaluate the heart function.The mRNA levels of potassium channel Ito （α subunit encoded by Kv4.3,Kv1.4）,IKs （α subunit encoded by KvLQT1,β subunit encoded by minK）,IKs（α subunit encoded by ERG,β subunit encoded by minK）,IK1 （α subunit encoded by Kir 2.1） in atrial myocytes were evaluated by real-time PCR.Results ①Compared with SO rabbits,HF rabbits exhibited the left ventricular and atrial enlargement（P ＜0.01）,systolic and diastolic dysfunction（P ＜ 0.01）,along with increased plasma BNP level and heart weight ratio（P ＜ 0.01）. ②Compared with HF rabbits,the heart function was improved significantly in rabbits after benapril intervention for 6 weeks,the enlarged left ventricle and artia were reduced（P ＜ 0.01）,and the BNP level and hear weight ratio decreased.（③）Compared with SO rabbits,mRNA levels of Kv4.3,Kv1.4 in HF rabbits were decreased by 59％ （P ＜ 0.01） and 47％ （P ＜ 0.01）.Levels of KvLQT1 and minK mRNA were decreased by 29％ （P ＜ 0.01） and 32％ （P ＜ 0.01）,and Kir2.1 mRNA level was decreased by 22％ （P ＜ 0.01） in heart failure rabbits.④Compared with heart failure rabbits,mRNA levels of Kv4.3,KvLQT1 and minK were increased by 29％ （P ＜ 0.01）,18％ （P ＜ 0.01） and 14％ （P ＜ 0.01） in rabbits after treatment.⑤）Kv1.4 and Kir2.1 mRNA levels had no changes between HF and BHF rabbits （P ＞ 0.05）
出处
《山西医科大学学报》
CAS
2014年第11期1005-1009,共5页
Journal of Shanxi Medical University
基金
国家自然科学基金重点项目(30830051)
关键词
心力衰竭
动物模型
钾通道
贝那普利
heart failure
animal models
potassium channels
benapril
