摘要
目的探讨糖尿病心肌病大鼠心肌中ErbB2受体表达和磷酸化的改变。方法选取8周龄雄性SD大鼠36只。按电脑随机数法分为:4周糖尿病组、4周对照组、12周糖尿病组、12周对照组。腹腔注射链脲佐菌素(streptozotocin,STZ)诱导糖尿病模型。分别在诱导糖尿病后第4、12周测定大鼠心脏质量,计算心脏质量/体质量,采用心脏超声评估大鼠心功能;采用Masson染色方法观察大鼠心肌间质纤维化程度并计算心肌胶原容积分数(collagen volume fraction,CVF);采用实时聚合酶链反应(PCR)方法检测大鼠心肌组织ErbB2受体mRNA的表达水平;采用蛋白免疫印记法(Western-blot)检测大鼠心肌组织ErbB2受体蛋白磷酸化水平。结果与同期对照组相比,第4,12周糖尿病组心脏质量/体质量均明显增高,差异有统计学意义[(3.41±0.12)mg/g vs.(2.32±0.22)mg/g,P<0.01;(3.72±0.38)mg/g vs.(2.39±0.0.26)mg/g,P<0.01]。第4,12周糖尿病组心肌CVF均明显高于同期对照组,差异有统计学意义[4.48%±0.21%vs.2.79%±0.36%,P<0.01;15.29%±0.67%vs.3.01%±0.13%,P<0.01]。4周糖尿病组的左心室收缩末内径、左心室射血分数、心肌组织ErbB2受体mRNA表达和蛋白磷酸化水平与4周对照组比较,差异无统计学意义(P>0.05)。12周糖尿病组左心室收缩末内径大于12周对照组,差异有统计学意义[(3.570±0.232)mm vs.(3.060±0.376)mm,P<0.05]。12周糖尿病组左心室射血分数小于12周对照组,差异有统计学意义[72.5%±3.81%vs.82.6%±2.97%,P<0.01]。与12周对照组比较,12周糖尿病组心肌组织ErbB2受体mRNA表达显著减少,差异有统计学意义(0.73±0.22vs.1.05±0.33,P<0.01],ErbB2受体蛋白磷酸化水平也显著减少(0.87±0.01vs.0.95±0.02,P<0.01)。结论糖尿病大鼠心肌组织中ErbB2受体mRNA表达和蛋白磷酸化水平的下调参与了糖尿病心肌病的发展。
Objectives To explore the change of ErbB2 mRNA expression and phospho-ErbB2 level in the cardiac tissue of diabetic rats.Methods Thirty six male SD rats were randomly divided into 4 weeks＇diabetic group,4 weeks＇control group,12 weeks＇diabetic group,12 weeks＇control group.Diabetic rat model was induced by a single intraperitoneal injection of streptozotocin （STZ）（55mg/kg）.Body weight（BW）/heart weight（HW）,echocardiographic parameters,collagen volume fraction（CVF）,ErbB2 mRNA expression and phospho-ErbB2 level were observed at 4 weeks and 12 weeks respectively after the STZ administered.Results HW/BW significantly increased [（3.41±0.12）mg/g vs.（2.32±0.22）mg/g,P0.01;（3.72±0.38）mg/g vs.（2.39±0.026）mg/g,P0.01] in 4 and 12 weeks＇diabetic groups,when compared with 4 and 12 weeks＇control groups.CVF in 4 and 12 weeks＇diabetic groups [4.48%±0.21% vs.2.79%±0.36%,P0.01;15.29%±0.67% vs.3.01%±0.13%,P0.01] significantly increased than those of 4 and 12 weeks＇control groups.There was no statistical significance in left ventricular ejection fraction（LVEF）,Left ventricular systolic dimension（LVESD）,ErbB2 mRNA expression level and phospho-ErbB2 level between 4 weeks＇diabetic group and 4 weeks＇control group（P0.05）.Compared with 12 weeks＇ control group,LVEF decreased in 12 weeks＇diabetic group [72.50%±3.81% vs.82.60%±2.97%,P0.01].Compared with 12 weeks＇ control group,LVESD increased in 12 weeks＇diabetic group [（3.570±0.232） mm vs.（3.060±0.376） mm,P0.05].The expression of ErbB2 mRNA and phospho-ErbB2 level significant decreased in 12 weeks＇diabetic group [（0.73±0.22）vs.（1.05±0.33）,P0.01;（0.87±0.01） vs.（0.95±0.02）,P0.01],when compared with 12 weeks＇control group.Conclusions Reducing ErbB2 and ErbB2 signal conduction may participate in progression of diabetic rat cardiomyopathy.
出处
《岭南心血管病杂志》
2011年第3期228-231,254,共5页
South China Journal of Cardiovascular Diseases
基金
广西卫生厅自筹基金(项目编号:桂卫Z2010342)
