目的:探讨普罗帕酮对心脏左心室流出道自律细胞与心室肌细胞电生理效应的影响。方法:应用常规的玻璃微电极细胞内记录技术,观察普罗帕酮对豚鼠左心室流出道自律细胞与心室肌细胞动作电位0相幅值(APA),最大除极速率(Vm ax),动作电位时程(...目的:探讨普罗帕酮对心脏左心室流出道自律细胞与心室肌细胞电生理效应的影响。方法:应用常规的玻璃微电极细胞内记录技术,观察普罗帕酮对豚鼠左心室流出道自律细胞与心室肌细胞动作电位0相幅值(APA),最大除极速率(Vm ax),动作电位时程(APD),50%复极化时间(D50),90%复极化时间(D90)以及左心室流出道自律细胞最大除极速率(Vm ax)与自发电活动频率(HR)。结果:①用0.5μm o l/L的普罗帕酮灌流后与正常对照组相比左心室流出道自律细胞自发电活动频率(HR)显著下降(P<0.01);②用1μm o l/L的普罗帕酮灌流后与正常对照组相比左心室流出道自律细胞动作电位0幅值(APA)下降(P<0.05),动作电位时程(APD)及50%复极化时间(D50)升高(P<0.05),自发电活动频率(HR)显著下降(P<0.01);用1μm o l/L的普罗帕酮灌流对心室肌细胞的电生理效应影响并不明显。③用5μm o l/L的普罗帕酮灌流后左心室流出道自律细胞电生理活动减弱或消失;用5μm o l/L的普罗帕酮灌流后与正常对照组相比对心室肌细胞动作电位0幅值(APA)下降(P<0.05),动作电位时程(APD)及50%复极化时间(D50)升高(P<0.05)。④用10μm o l/L的普罗帕酮灌流后与正常对照组相比对心室肌细胞动作电位0幅值(APA)下降(P<0.05),动作电位时程(APD)明显升高(P<0.01),50%复极化时间(D50)及90%复极化时间(D90)升高(P<0.05)。结论:普罗帕酮能抑制左心室流出道自律细胞与心室肌细胞的动作电位0幅值,延长动作电位时程;使左心室流出道自律细胞自发电活动频率下降。展开更多
Objective: To study the changes of a collagen-binding protein (Colligin) and myosin heavy chain isoform (α/β-MHC) gene and protein in left ventricular hypertrophy subsequent to coarctation of abdominal aorta in rats...Objective: To study the changes of a collagen-binding protein (Colligin) and myosin heavy chain isoform (α/β-MHC) gene and protein in left ventricular hypertrophy subsequent to coarctation of abdominal aorta in rats and the effects of three kinds of adrenergic receptor blockers: Carvedilol (CAR) , Metoprolol (MET) and Terazosin (TER) on these changes, and to elucidate the effects and new mechanism of CAR on left ventricular hypertrophy regression. Methods: A model of hypertrophy induced by coarctation of abdominal aorta(CAA)was used in this study. Thirty two male wistar rats were divided randomly into four groups 4 weeks after CAA operation: CAA, CAR, MET and TER. Hemodynamics, ventricular remodeling parameters, expressions of Colligin and α/β-MHC mRNA, protein expressions of Collagen Ⅰ / Ⅲ and Colligin were investigated in the four groups and sham operation group. Results: Left ventricle hypertrophy was observed clearly 16 weeks after operation. The ratio of α/β-MHC mRNA decreased, while expressions of Collagen Ⅰ /Ⅲ proteins and Colligin mRNA/protein increased( P < 0.05). CAR could ameliorate left ventricle hypertrophy prior to MET and TER. CAR could also change the expressions of α/β-MHC, Collagen Ⅰ /Ⅲ and Colligin in both gene and protein levels ( P < 0.05), while MET and TER have no effect on them ( P > 0.05). Conclusion: The effects of CAR on extracellular matrix proteins and MHC isoform shift regression of left ventricle may be due to antiproliferative or antioxidative mechanism, which was independent of beta-adrenergic receptor antagonist.展开更多
文摘目的:探讨普罗帕酮对心脏左心室流出道自律细胞与心室肌细胞电生理效应的影响。方法:应用常规的玻璃微电极细胞内记录技术,观察普罗帕酮对豚鼠左心室流出道自律细胞与心室肌细胞动作电位0相幅值(APA),最大除极速率(Vm ax),动作电位时程(APD),50%复极化时间(D50),90%复极化时间(D90)以及左心室流出道自律细胞最大除极速率(Vm ax)与自发电活动频率(HR)。结果:①用0.5μm o l/L的普罗帕酮灌流后与正常对照组相比左心室流出道自律细胞自发电活动频率(HR)显著下降(P<0.01);②用1μm o l/L的普罗帕酮灌流后与正常对照组相比左心室流出道自律细胞动作电位0幅值(APA)下降(P<0.05),动作电位时程(APD)及50%复极化时间(D50)升高(P<0.05),自发电活动频率(HR)显著下降(P<0.01);用1μm o l/L的普罗帕酮灌流对心室肌细胞的电生理效应影响并不明显。③用5μm o l/L的普罗帕酮灌流后左心室流出道自律细胞电生理活动减弱或消失;用5μm o l/L的普罗帕酮灌流后与正常对照组相比对心室肌细胞动作电位0幅值(APA)下降(P<0.05),动作电位时程(APD)及50%复极化时间(D50)升高(P<0.05)。④用10μm o l/L的普罗帕酮灌流后与正常对照组相比对心室肌细胞动作电位0幅值(APA)下降(P<0.05),动作电位时程(APD)明显升高(P<0.01),50%复极化时间(D50)及90%复极化时间(D90)升高(P<0.05)。结论:普罗帕酮能抑制左心室流出道自律细胞与心室肌细胞的动作电位0幅值,延长动作电位时程;使左心室流出道自律细胞自发电活动频率下降。
文摘Objective: To study the changes of a collagen-binding protein (Colligin) and myosin heavy chain isoform (α/β-MHC) gene and protein in left ventricular hypertrophy subsequent to coarctation of abdominal aorta in rats and the effects of three kinds of adrenergic receptor blockers: Carvedilol (CAR) , Metoprolol (MET) and Terazosin (TER) on these changes, and to elucidate the effects and new mechanism of CAR on left ventricular hypertrophy regression. Methods: A model of hypertrophy induced by coarctation of abdominal aorta(CAA)was used in this study. Thirty two male wistar rats were divided randomly into four groups 4 weeks after CAA operation: CAA, CAR, MET and TER. Hemodynamics, ventricular remodeling parameters, expressions of Colligin and α/β-MHC mRNA, protein expressions of Collagen Ⅰ / Ⅲ and Colligin were investigated in the four groups and sham operation group. Results: Left ventricle hypertrophy was observed clearly 16 weeks after operation. The ratio of α/β-MHC mRNA decreased, while expressions of Collagen Ⅰ /Ⅲ proteins and Colligin mRNA/protein increased( P < 0.05). CAR could ameliorate left ventricle hypertrophy prior to MET and TER. CAR could also change the expressions of α/β-MHC, Collagen Ⅰ /Ⅲ and Colligin in both gene and protein levels ( P < 0.05), while MET and TER have no effect on them ( P > 0.05). Conclusion: The effects of CAR on extracellular matrix proteins and MHC isoform shift regression of left ventricle may be due to antiproliferative or antioxidative mechanism, which was independent of beta-adrenergic receptor antagonist.