热休克蛋白27心肌特异性高表达诱导小鼠产生心肌肥厚

目的探讨不同表达量的热休克蛋白27（Hsp27）在小鼠心脏中的作用。方法构建在心肌中特异性表达Hsp27的不同表达量的转基因鼠（TG），对照组为野生型鼠（WT）。采用蛋白印记测定Hsp27蛋白表达水平；分别测量心脏质量与体质量的比值和心脏质量与胫骨长度的比值（HW／BW和HW／TL）；采用实时定量荧光PCR（real time PCR）技术测定心肌肥厚标记物心房利钠肽（ANP）、脑利钠肽（BNP）的表达；采用超声心动图观察心功能及心脏结构。通过长期饲养，观察存活率。结果不同TG系鼠，Hsp27心肌特异性表达水平不同。高表达TG10鼠与WT鼠相比，其HW／BW和HW／TL比值显著增加（P〈0．01），并且ANP和BNP的mRNA水平也明显增加（P〈0．01）。TG10鼠的心功能与WT鼠比较显著下降（P〈0．01），射血分数（EF）降低了24．64％，短轴缩短率（VS）降低了29．37％。TG10鼠的生存率明显降低（P〈0．01）。结论高表达的Hsp27在TG鼠心肌肥厚发展中起着重要作用，提示Hsp27可以作为心肌病患者治疗的潜在靶点。

Cardiac-specific expression of Hsp27 induced mice cardiac hypertrophy

Objective To investigate the effects of different expression levels of heat shock protein 27 （Hsp27） on mice heart. Methods Trangenic（TG） mouse models with specific over-expressed Hsp27 in heart were constructed, and wild type（WT） mice were chosen as control. Hsp27 level was determined by Western blotting. The ratio of heart weight versus body weight（HW/BW） and the ration of heart weight versus tibia length （HW/TL） were calculated. The expression of hypertrophy markers such as atrial natriuretic peptide（ ANP ） , brain natriuretic peptide （BNP） was detected by real time- PCR. Cardiac function and cardiac structure were observed by echocardiography. The survival rate was obtained through long-term feeding. Results Differerrt expression levels of Hsp27 in heart were found in different TG mice. HW/BW and HW/TL were increased in TG10 group （P〈0.01）, and the mRNA expression level of ANP and BNP was increased（ P〈 0. 01 ）. Cardiac function in TG10 group was more significantly decreased than that in WT group, with EF decreased by 24. 64%, FS decreased by 29.37%. The survival rate of TG10 group was significantly decreased （P〈 0. 01 ）. Conclusions Over expression of Hsp27 plays an important role during the process of cardiac hypertrophy in TG mice. Hsp27 may act as a larvaceous target for the treatment of patients with cardiomyopathy.