摘要
目的研究钙离子结合蛋白S100B在心力衰竭大鼠心肌细胞中的表达变化。方法清洁级雄性Sprague-Dawley大鼠，体重（220～240）g，由浙江大学医学院实验动物中心提供。通过缩窄腹主动脉建立心力衰竭大鼠模型，术后第二周仍存活的20只大鼠随机分为手术组（10只）和卡维地洛组（10只），在术后第2周各以生理盐水和卡维地洛灌胃，共4周。假手术组（10只）仅分离腹主动脉不束扎。术后第6周，应用MEDLAB-U／4CS生物信号采集系统测定血流动力学。麻醉处死后，取左室心肌检测S100B蛋白表达，RT-PCR法测定S100BmRNA水平。计量资料以均数±标准差（-↑x±s）表示，多组间比较应用单因素方差分析法进行分析，两两间比较应用Student-Newman-Keulsa法进行检验。P〈0．05认为差异具有统计学意义。结果与假手术组比，手术组左心室舒张末压（LVEDP）升高[（24．8±5．2）mmHg vs．（2．1±0．7）mmHg]，左心室内压最大收缩和舒张速率（±dp／dtmax）下降[（1543．6±277．9）mmHg／s vs．（2640．4±481．3）mmHg／s和（-1352．5±202．3）mmHg／s vs．（-1873．2±412．3）mmHg／s]，差异有统计学意义（P〈0．01，P〈0．01和P〈0．05）。卡维地洛组的LVEDP（12．7±1．1）mmHg，介于手术组和假手术组之间，差异有统计学意义（P〈0．01）；±dp／dtmax为（2372．3±92．6）mmHg／s和（-1786．4±62．6）mmHg／s，明显高于手术组，差异有统计学意义（P〈0．01）。假手术组心肌没有S100B阳性细胞和S100BmRNA表达；手术组心肌有大量胞浆棕黄色的S100B阳性细胞和S100BmRNA表达；卡维地洛组S100B阳性细胞数明显减少而且S100BmRNA水平低，差异有统计学意义（P〈0．01）。S100BmRNA表达量与LVEDP、＋dp／dtmax、-dp／dtmax相关，相关系数r=0．847、-0．853、-0．689，P均〈0．01。结论S100B在衰竭心肌细胞中表达明显增多，与心功能呈负相关；在心力衰竭中起负调控作用。
Objective To evaluate the value of S100B gene on cardiovascular remodeling in rats with abdominal aorta coarctation. Method Sprague-Dawley rats （ sanitary degree, male ）, weighting （220 - 240）g, were used in the study. They were provided by College of Medicine, Zhejiang University. The abdominal aortas of rats were isolated and constricted so as to establish models of heart failure; the abdominal aortas of another ten rats were isolated but not ligated （sham-operation group）. After one week, the 20 rats were alive and randomly divided into 2 groups：operation group （ n = 10）and Carvidilol-operation group （Car group, n = 10）. Car Group was treated with 2 mg· kg^-1 per day Carvedilol and operation group was administered with the same doses of normal saline. After 4 weeks, a catheter was inserted through the right jugular artery into the left ventricle to record hemodynamic. Then all rats were euthanized, and the heart tissues were rapidly excised, rinsed with PBS. The left ventricles were then cut into two parts at the equator： the upper sections were fixation, the lower sections were stored at - 80℃ ,at 100 mg per tube. LV transverse section （4μm thick） was subjected to S100B immunehistoc-hemistry. RNA was isolated from tissues by TRIzol to determine levels of S100BmRNA and β-actinmRNA by RT- PCR. The data was expressed as （-↑x ± s） ; One-way analysis of variance was used for comparison among groups, and Student-Newman-Keulsa test for comparison between two groups. Statistical significance was set at P 〈 0.05. Results In Operation Group, there was a decrease in maximal rate of systolic and diastolic of left ventricular pressure（± dp/dtmax） [（1543.6±277.9） mmHg/s vs. （2640.4±481.3） mmHg/s and（ - 1352.5±202.3） mmHg/s vs. （ - 1873.2± 412.3） mmHg/s] ; and an increase in left ventricular end diastolic pressure （LVEDP） [ （24.8 ± 5.2） mmHg vs. （2.1 ± 0.7） mmHg] compared with sham-operation group （ P 〈 0.01, P 〈 0.01 and P 〈 0.05）. And in Car group, the level of LVEDP was just in the midst of the Operation Group and sham-operation group, and had statistical significance （P 〈 0.01）; while ± dp/dtmax [（2372.3 ± 92.6） mmHg/s and （ - 1786.4±62.6） mmHg/s] were much higher than those in operation group （P 〈 0.01）. There were no any S100B positive cells and expression of S100B mRNA in sham-operation group; while there were much more S100B positive cells in operation group than those in Car group （ P 〈 0.01 ）. The expression of S100B mRNA in operation group was more pronounced than that in Car group. Changes in expression of S100BmRNA were positively correlated with changes in LVEDP （ r = 0. 847, P 〈 0.01 ） ; while changes in expression of S100BmRNA were negatively correlated with changes in ±dp/dt max（ r = -0.853 and -0.689, both P 〈 0.01）. Conclusions There was high expression of S100B in myocytes from rats with experimental heart failure and negative correlation between the expression of S100B and heart function. It indicated that S100B could play a negative role in heart failure.
出处
《中华急诊医学杂志》
CAS
CSCD
2008年第5期475-478,共4页
Chinese Journal of Emergency Medicine
基金
浙江省教育厅资助（编号：20030314）
