心衰心肌细胞肌浆网钙泵对兴奋收缩偶联功能的影响

SERCA influences excitation-contraction coupling in heart failure rats

目的:研究钙泵介导的钙回摄对成年大鼠心室肌细胞兴奋收缩偶联功能的影响。方法:急性分离正常组和心衰组大鼠心室肌细胞,采用激光扫描共聚焦显微镜研究肌浆网的钙容量,然后利用异丙肾上腺素(ISO,1μmol/L)激活心肌细胞β-肾上腺素受体后采用激光扫描共焦显微镜记录其对心肌细胞介导的钙释放;采用Western-blot分析心肌细胞肌浆网钙泵表达水平。结果:心衰组的钙容量显著低于对照组(n=10,P<0.01);ISO胞外灌流后,心衰组心肌细胞钙释放水平显著降低(n=10,P<0.05);心衰组钙泵表达水平低于对照组(n=6,P<0.01)。结论:钙泵介导的钙回摄能影响心肌细胞肌浆网钙容量,并进一步影响心肌细胞兴奋收缩偶联的功能。

Object： The influence of SERCA-mediated calcium reuptake on ECC in rat ventricular myocytes was investigated.Method： Ventricular myocytes are isolated in Langendorrf perfusion device,and SR calcium content is measured by laser scanning confocal microscope;ISO（1 μmol /L） is employed as β-adrenergic receptor stimulator to activate the calcium release from SR,and clarify the relationship between calcium release and reuptake;western blot method is used to analyze the differences in expression levels of SERCA in ventricular myocytes.Result： Calcium content of SR in HF myocytes is significantly slower（n = 10,P 0.01）;after stimulation by ISO,the frequency of calcium sparks has a large decreases（n = 10,P 0.05） compared with control myocytes;the expression of SERCA is downregulated（n = 6,P 0.01） in a large scale in HF myocytes.Conclusion： SERCA-mediated calcium reuptake influences the calcium content of SR,which changes the ECC function in rat ventricular myocytes.