肥胖大鼠心律失常易感性的分析  

Experimental Study on Mechanism of Different Susceptibility to Obesity Induced Arrhythmia

作　　者：郝艳坤[1] 吴琦[1] 栾海蓉[1] 许晓义[1] 

机构地区：[1]牡丹江医学院动物技能教研室,黑龙江牡丹江157011

出　　处：《医学综述》2010年第12期1895-1898,共4页Medical Recapitulate

基　　金：黑龙江省卫生厅科研课题(2007-011)

摘　　要：目的研究高脂饮食诱导肥胖易感(OP)大鼠心律失常易感性的发生机制。方法高脂饲料喂饲60只健康雄性SD大鼠12周后,筛选出OP大鼠、基础组大鼠动物模型,二组分别为15只大鼠。实验结束后,处死动物,测量体脂肪水平,并收集血清,以检测血脂水平。采用酶法分离心肌细胞,Fluo-3/AM负载后采用激光共聚焦扫描显微镜观察各组大鼠心肌细胞内钙离子强度([Ca2+]i)。同时取心脏组织常规抽提总RNA,采用含有468种miRNA的芯片检测系统进行miRNA表达谱差异分析。结果 OP大鼠睾周脂肪、肾周脂肪、网膜脂肪、体脂比[(20.15±3.38)、(8.74±1.66)、(9.23±0.94)、(7.71±0.74)mmol/L]均显著高于基础组大鼠[(8.98±1.19)、(4.70±0.59)、(6.28±0.40)、(4.69±0.37)mmol/L],OP组与基础组比较差异有统计学意义(P<0.05);OP大鼠血清总胆固醇、三酰甘油和低密度脂蛋白水平[(1.26±0.04)、(0.58±0.10)、(0.51±0.04)mmol/L]显著高于基础组大鼠[(0.92±0.08)、(0.29±0.03)、(0.31±0.04)mmol/L],OP组与基础组比较差异有统计学意义(P<0.05);OP组大鼠心室肌细胞内游离钙离子荧光强度(247.96±20.03)明显高于基础组大鼠(174.25±23.13),OP组与基础组比较差异有统计学意义(P<0.05)。与基础组相比,OP模型组的miRNA表达谱中明显差异表达的miRNA共有7个,其中有3个miRNA上调,4个miRNA下调。结论肥胖大鼠miRNA的表达异常可导致心肌细胞内[Ca2+]i发生改变,可能是肥胖心律失常发生机制之一。Objective To study the mechanism of arrhythmia in myocardirl cell of obesity prone（OP）rats induced by high-fat diet.Methods Male Sprague-Dawley（SD）rats were divided into OP rats（n=15）and control group rats（n=15）after fed with high-fat diet for 12 weeks.After the rats were sacrificed,body fat content was measured and serum was collected to measure serum lipids.Myocardial cells were then isolated with enzymic method and intracellular calcium lever（[Ca^2＋]i）was measured with calcium indicator Fluo-3 /AM and laser scanning confocal microscope.Total RNA was extracted from myocardium and the differential expression of miRNA was detected by miRNA array.Results Epididymal fat,perirenal fat,omental fat and body fat content were significantly higher in OP rats[（20.15±3.38）、（8.74±1.66）、（9.23±0.94）、（7.71±0.74）]mmol/L]than that in control group rats[（8.98±1.19）、（4.70±0.59）、（6.28±0.40）、（4.69±0.37）mmol/L]（P〈0.05）.The level of total cholesterol（T-CHO）,triglyceride and low density lipoprotein were significantly higher in OP rats[（1.26±0.04）、（0.58±0.10）、（0.51±0.04）mmol/L]than that in control group rats[（0.92±0.08）、（0.29±0.03）、（0.31±0.04）mmol/L]（P〈0.05）.The fluorescence intensity standing for[Ca^2＋]i was increased significantly in OP rats（247.96±20.03）compared with control group rats（174.25±23.13）（P〈0.05）.To contrast control group rats,seven miRNAs showed differentially expression,three were up-regulated and four down-regulated.Conclusion Expression changes of microRNAs induced to the accumulated cytosolic calcium in myocardium of OP rats that contributed to obesity induced arrhythmia.

关 键 词：肥胖 激光共聚焦扫描显微镜 细胞内钙 MIRNA 心律失常 

分 类 号：R-331.31[医药卫生]