摘要
目的:研究心肌梗死后心力衰竭大鼠左心室非梗死区β受体密度和 mRNA表达的变化,同时观察卡维地洛和美托洛尔两类不同的β受体阻滞剂对其影响。方法:结扎大鼠冠状动脉前降支,形成广泛前壁心肌梗死,而后经过4周的左室重构,导致心力衰竭形成。手术组死亡率为43%,假手术组死亡率为4.7%。实验分为 4周和12周2个时间点进行。取手术组存活的50只大鼠随机分为 5 组:4 周手术(4O)组,美托洛尔 20 mg(M20)组,卡维地洛10 mg(C10)组,卡维地洛1 mg(C1)组,12周手术(12O)组;取假手术组存活的 20 只大鼠随机分为 2组:4周假手术(4S)组,12 周假手术(12S)组;每组均为 10 只大鼠。另外取 10 只正常大鼠作为 4 周正常对照(4N)组。M 20、C10和C1 组于术后4周开始给药;各组大鼠分别于术后4、12周取左心室非梗死区心肌,测定β受体密度及β1 和β2 受体mRNA。结果:4周时,心力衰竭组β受体密度(P<0.01)和β1 受体 mRNA表达(P<0.05)显著降低。12周时,美托洛尔显著增加β受体密度(P<0.01)和β1 受体 mRNA表达(P<0.05),卡维地洛没有增加β受体密度和β1 受体 mRNA表达的作用。结论:心力衰竭时β受体密度和β1 受体 mRNA表达降低,卡维地洛对β受体密度和β1 受体mRNA表达没有明显影响。
Objective:The aim of present study is to study the alteration of β-receptor density and β 1, β 2 mRNA expression in failing heart after myocardial infarction in rats. We also study the effects of two different β-blockers carvedilol and metoprolol on these parameters. Method: Ischemic heart failure model was made on male SD rats. Fifty rats were randomly divided into 5 groups after operation: 4-weeks operation(4O) group, Metoprolol 20 mg(M 20) group, Carvedilol 10mg(C 10) group, Carvedilol 1mg (C 1) group, 12-week operation(12O)group. Twenty rats were randomly divided into 2 groups after sham-operation:4-week sham-operated(4S) group,and 12-week sham- operated(12S)group. The rest ten normal rats were used as 4-week normal(4N) group.There were ten rats in each group, the rats were given metoprolol and carvedilol by gastric gavage 4 weeks after operation. At 4 and 12 weeks,non-infarcted left ventricular tissue was divided into several pieces for measuring β-receptor density and β-receptor mRNA. β-receptor density was measured by radioligand method. β-receptor mRNA level was quantified by reverse transcription-polymerase chain reaction(RT-PCR). The results were analyzed using SPSS10.0 software system. Data are expressed as means±SE.Comparisions between groups were performed by one-way ANOVA test.Result:At 4 weeks, β-receptor density and β 1-receptor mRNA expression were significantly decreased in 4O group compared to the two control groups.At 12 weeks, β-receptor density and β 1-receptor mRNA expression were significantly increased in M20 group compared to 12O group,there were not change in two carvedilol groups.Conclusion: Metoprolol significantly increase β-receptor density and β 1-receptor mRNA expression,the effect of carvedilol was not significant.
出处
《临床心血管病杂志》
CAS
CSCD
北大核心
2005年第3期164-166,共3页
Journal of Clinical Cardiology
关键词
心肌梗死
心力衰竭
受体
肾上腺素能β
Β受体阻滞剂
Myocardial infarction
Heart failure
Receptor,adrenergic,beta
β-adrenergic receptor blocker
