摘要
目的探讨家兔心衰心肌细胞钙渗漏与蛋白激酶A(PKA)和Ca2+/钙调蛋白依赖性激酶Ⅱ(CaMKⅡ)表达和活性的关系。方法 30只家兔随机均分为假手术组和心衰组。通过超容量负荷联合压力负荷制备家兔心衰模型,用心脏多谱勒和心导管术测定家兔心脏功能,应用钙成像系统进行肌浆网钙回摄和钙渗漏试验。采用Western blot法和γ-32P掺入法测定CaMKⅡ和PKA的蛋白表达水平和活性;应用ELISA法测定血浆去甲肾上腺素(NE)、肾上腺素(E)和脑钠肽(BNP)水平。结果与假手术组相比,心衰组家兔左室舒张末压、血浆NE、E和BNP水平均明显增加(P<0.01),而射血分数明显降低(P<0.01),肌浆网钙回摄功能下降(P<0.05),而钙渗漏增加(P<0.01),PKA的蛋白表达水平和活性均下降(P<0.05),而CaMKⅡ蛋白表达水平和活性均增加(P<0.05)。结论家兔心衰心肌细胞钙渗漏与CaMKⅡ蛋白表达水平和活性增加相关。
Objective To investigate the relationship between calcium leak and the expression and activity of Ca2＋/calmodulin-dependent protein kinase-Ⅱ（CaMKⅡ） in myocytes of rabbits with heart failure（HF）.Methods Thirty rabbits were divided into two groups of sham operation and HF with 15 rats each.HF model was established by volume plus pressure overloading.Cardiac function was measured via echocardiography and catheterization.Calcium uptake and leak assay were determined using fluorescence spectroscopy.The expression and activity of protein kinase（PKA） and CaMK Ⅱ were determined by Western blot and [γ-32P] ATP-binding assays,respectively.Plasma norepinephrine（NE）,epinephrine（E） and brain natriuretic peptide（BNP） were determined using ELISA.Results Compared to sham operation group,HF group showed significant decreases in the left ventricular end diastolic pressure,ejection fraction,calcium reuptake of sarcoplasmic reticulum（SR）,and the expression and activity of PKA,but significant increases in plasma levels of NE,E and BNP,calcium leak,and the expression and activity of CaMK Ⅱ（P0.01 or P0.05）.ConclusionThe SR calcium leak is increased in rabbits with heart failure,which is related to increased expression and activity of CaMK Ⅱ.
出处
《江苏医药》
CAS
CSCD
北大核心
2011年第2期125-128,共4页
Jiangsu Medical Journal
基金
国家自然科学基金青年基金项目(30800460)
