Presenilin1基因对心肌细胞肌浆网钙容量的影响

Effect of presenilin1 on thesarcoplasmic reticulum calcium capacity in cardiomyocytes

目的:探讨Presenilin1基因对心肌细胞肌浆网钙容量的影响。方法:本实验以AAV-9为载体构建心肌特异性PS1-shRNA重组腺相关病毒,通过尾静脉注射PS1-shRNA重组腺相关病毒干扰大鼠心肌组织中Presenilin1基因的表达,并利用激光扫描共聚焦显微镜检测并记录心肌细胞肌浆网钙容量及舒张期自发钙释放事件的变化;同时,采用western blot技术分析各组大鼠心肌组织中雷诺丁受体及钙泵表达水平的改变。结果:与对照组相比,PS1-shRNA重组腺相关病毒干预组大鼠心肌细胞肌浆网钙容量显著降低,自发钙释放事件明显增加;雷诺丁受体表达水平略降低,钙泵表达水平无显著性变化。结论:Presenilin1基因表达水平降低会引起心肌细胞钙泄漏,从而造成心肌细胞肌浆网钙容量降低。

Objective: To study the effect of presenilin1 on the sarcoplasmic reticulum calcium capacity in cardiomyocytes.Methods: The AAV-9vector was used to contruct myocardial specifically PS1-shRNA recombinant adeno-associated virus and the myocardium of rats was transfected through tail intravenous injection of the PS1-shRNA recombinant adeno-associated virus. Changes of sarcoplasmic reticulum calcium capacity and spontaneous Ca^(2+)release events during diastolic were detected by laser scanning confocal microscopy. Expression level of reynoldie receptor and Ca^(2+)-ATPase in myocardium of each group was analyzed by western blot.Results: Compared with the reference group, the sarcoplasmic reticulum calcium capacity in cardiomyocytes of PS1-shRNA recombinant adeno-associated virus intervention group was significantly reduced,and the frequency of the spontaneous Ca^(2+)release events increases markedly during diastolic. The expression level of reynoldie receptor was decreased slightly and there was almost no change in the level of Ca^(2+)-ATPase. Conclusion: The decreased level presenilin1 may cause Ca^(2+) leakage,resulting in the decrease of sarcoplasmic reticulum calcium capacity.