舒张性心力衰竭兔Ca^(2+)调控蛋白相关基因表达的变化  

Molecular mechanism underlying calcium handling in diastolic heart failure

作　　者：钟明[1] 张运[2] 张薇[2] 卞继峰[3] 葛志明[2] 卜培莉[2] 耿昭[3] 季晓平[2] 赵静[2] 

机构地区：[1]山东大学齐鲁医院干部保健科,济南250012 [2]山东大学齐鲁医院心内科,济南250012 [3]山东大学分子生物学实验室

出　　处：《中华医学杂志》2001年第11期669-672,共4页National Medical Journal of China

基　　金：国家自然科学基金资助项目 ( 39970 2 94)

摘　　要：目的　探讨舒张性心力衰竭 (DHF)时Ca2 + 调控蛋白相关基因表达的变化 ,以阐明DHF发生的分子机制。方法　建立DHF兔模型 ,并设假手术为对照组 ,分别测定 2组兔心肌细胞内Ca2 +含量和肌浆网 (SR)Ca2 + ATPase(钙泵 )活性 ,并以定量RT PCR和Westernblot技术检测Ca2 + 调控蛋白相关基因的转录和蛋白质表达水平。结果　 (1)DHF兔心肌细胞内Ca2 + 含量 (μg/ml)显著高于对照组(172 8± 5 45vs 6 33± 16 8,P <0 .0 1) ;(2 )DHF兔SR钙泵活性 ,细胞膜L型Ca2 + 通道和SR钙泵mRNA水平 (μmol·mg-1·h-1)明显低于对照组 (10 .5± 2 .8vs 2 1.1± 5 7;0 .75± 0 .11vs 1.2 0± 0 .33;0 .76±0 12vs 1.2 4± 0 .38,P <0 .0 5～ 0 .0 1) ;(3)DHF兔细胞膜L型Ca2 + 通道mRNA水平与左室舒张末压中度负相关 (r=- 0 .74,P <0 .0 5 ) ,SR钙泵mRNA水平与左室舒张末压和左室松弛时间常数中度负相关 (r分别为 - 0 .81、- 0 .6 4,P <0 .0 5～ 0 .0 1) ;DHF兔兰尼碱受体mRNA水平与左室松弛时间常数负相关 (r =- 0 .71,P <0 .0 5 ) ;(4)DHF兔SR钙泵的蛋白质表达明显低于对照组 (0 .75± 0 .0 6vs 1.0 2±0 0 9,P <0 .0 5 )。结论　细胞膜L型Ca2 + 通道和SR钙泵mRNA和蛋白质表达减低是导致心肌细胞内Ca2 + 超负荷及DHF发生的?Objective To elucidate the molecular mechanism underlying calcium handling in diastolic heart failure (DHF) from mRNA level and protein expression, including L type calcium channel, sarcoplasmic reticulum (SR) Ca 2+ ATPase, phospholamban, ryanodine receptor, calsequestrin. Methods DHF was produced in rabbits by abdominal aortic coarctation. The mRNA amounts of these calcium handling genes were measured by RT PCR, while the protein levels of SR Ca 2+ ATPase and phospholamban were analyzed by Western blot analysis. Results The content of calcium was significantly increased in myocardium of rabbits with DHF than in the myocardium of sham operated rabbits. The SR Ca 2+ ATPase activity of DHF rabbits was significantly reduced compared with that in sham operated rabbits (21.1 μmol·mg -1 ·h -1 ±5.7 μmol·mg -1 ·h -1 vs 10.5 μmol·mg -1 ·h -1 ±2.8 μmol·mg -1 ·h -1 , P<0.01). RT PCR analyses showed that the steady state level of mRNA encoding the L type calcium channel and SR Ca2+ ATPase was decreased significantly in rabbits with DHF compared with that in the sham operated rabbits (μmol·mg -1 ·h -1 ): 0.75±0.11 vs 1.20±0.33;0.76±0.12 vs 1.24±0 38, P <0.05). The SR Ca 2+ ATPase mRNA level correlated negatively well with left ventricular relaxation time constant and left ventricular end diastolic pressure( r =-0.81,-0.64,respectively, P <0.05～0.01);the mRNA level of L type calcium channel correlated negatively with left ventricular end diastolic pressure ( r = -0 74, P <0.05). The mRNA level of ryanodine receptor correlated negatively with the left ventricular relaxation time constant too ( r =-0.71, P <0.05). Protein level of SR Ca 2+ ATPase was significantly lower in rabbits with DHF than in the sham operated rabbits (0.76±0.6 vs 1.02±0.09, P <0.05), whereas the protein level of phospholamban was unchanged. Conclusion The L type calcium channel and SR Ca 2+ ATPase were down regul

关 键 词：舒张性心力衰竭 钙调蛋白 基因表达 实验研究 

分 类 号：R541.6[医药卫生—心血管疾病]