中文摘要：

目的 观察心脏转染整合素连接激酶（ILK）对心力衰竭大鼠心功能的影响,并初步探讨其机制.方法 腹腔注射阿霉素（总剂量15 mg/kg,2周内分6次注射）建立大鼠心力衰竭模型.5周后通过心脏超声筛查,将成功建模的大鼠按照随机数字表法随机分为转染Ad-ILK组（Ad-ILK组）和转染Ad-null组（对照组）,每组20只.通过开胸左心室多点注射Ad-ILK或Ad-null,4周后采用蛋白质免疫印迹法检测ILK蛋白表达水平及其活性,超声心动图、心导管法检测大鼠心功能,ELISA法检测大鼠血清B型利钠肽（BNP）表达水平,并采用TUNEL法检测心肌细胞凋亡率,磷酸化组蛋白H3免疫荧光染色检测心肌细胞增殖率.结果 转染4周后,Ad-ILK组大鼠心脏组织中ILK蛋白表达水平明显高于对照组（P＜0.05）,其下游蛋白激酶B（Akt）磷酸化水平也明显高于对照组（P＜0.05）.转染4周后,Ad-ILK组大鼠左心室射血分数和短轴缩短率均明显高于对照组[（60.56±2.61）％比（51.94±2.28）％和（28.10±1.83）％比（22.82±1.68）％,P均＜0.05],左心室舒张末期内径和收缩末期内径均明显小于对照组[（6.22±0.24） mm比（7.15±0.21） mm和（4.42±0.23） mm比（5.65±0.25） mm,P均＜0.05],左心室舒张末压明显低于对照组[（12.96±2.10） mmHg比（21.45±2.48） mmHg（1 mmHg =0.133 kPa）,P＜0.05].Ad-ILK组大鼠血清B型利钠肽水平亦明显低于对照组（P＜0.05）.Ad-ILK组心肌细胞凋亡率明显低于对照组[（0.23±0.02）％比（0.45±0.04）％,P＜0.05],而心肌细胞增殖率则显著高于对照组[（0.60±0.07）％比（0.24±0.03）％,P＜0.01].结论 心肌注射转染Ad-ILK能够明显改善心力衰竭大鼠心功能,这一作用可能与过表达ILK能够抑制心肌细胞凋亡、促进心肌细胞增殖有关.

英文摘要：

Objective The aim of this study is to investigate the effects of cardiac integrin-linked kinase （ILK） overexpression in a rat model of doxorubicin-indueed heart failure and the underlying mechanisms. Methods Rat heart failure model was induced by intraperitoneal administration of doxorubicin （6 injections within 2 weeks： total dose = 15 mg/kg）. Five weeks after the first injection, rats with heart failure were confirmed by echocardiography and then randomly divided into Ad-ILK group （intramyocardially injected with adenoviral vector expressing ILK） and Ad-null group （intramyoeardially injected with empty ad-null, n =20 each）. After 4 weeks, ILK expression and activity were detected by Western blot, cardiac function was determined by echocardiographie and hemodynamic examinations. Apoptosis was measured by TUNEL analysis and cardiomyocyte proliferation was estimated by phosphohistone-H3 staining. Results Western blot analysis revealed higher expression of ILK as well as the phospholylation levels of Akt in Ad- ILK hearts as compared with ad-null controls. Four weeks after transfection, LVEF and LVFS were significantly higher in Ad-ILK group as compared with control grotlp LVEF： （60. 56 ±2.61 ）% vs. （51.94±2.28）%, P〈0.05; LVFS： （28. 10± 1.83）% vs. （22.82 ± 1.68）%, P 〈0.05]. The LVEDD and LVESD, as well as LVEDP were significantly lower in Ad-ILK group compared with control group [LVEDD： （6.22±0.24） mmvs. （7.15±0.21） ram, P〈0.05; LVESD： （4.42±0.23） mmvs. （5.65 ±0.25） ram, P〈0.05; LVEDP： （12.96±2.10） mmHgvs. （21.45±2.48） mmHg（1 mmHg=0. 133 kPa） , P 〈0. 05]. Reduced levels of serum BNP was also seen in the Ad-ILK group. TUNEL analysis showed that ILK treatment significantly inhibited the apoptosis of cardioInyoeytes [ （ 0. 23 ± 0. 02 ） % vs. （0. 45 ± 0.04）% , P 〈 0. 05 ]. Moreover, increased cardiomyocyte proliferation was found in Ad-ILK group through the phospho-histone H3 staining [ （0. 60 ± 0.07 ） % vs. ?