摘要
目的观察正常家兔三层心肌间跨室壁缝隙连接蛋白43(Cx43)分布的差异,探讨恶性室性心律失常(MVA)的发生机制。方法检测并对比正常家兔左心室三层心肌间的单相动作电位复极90%时程(APD_(90))以及Cx43蛋白(Cx43-pro)和m RNA(Cx43-Cq)的表达差异。结果 (1)正常家兔三层心肌间APD_(90)存在差别,中层心肌(233.80±19.37)组织APD_(90)均长于心内膜(201.20±18.72)和心外膜下(202.70±19.91)心肌组织(P<0.05),说明家兔三层心肌间存在跨室壁复极的离散;(2)正常家兔三层心肌间的Cx43-pro[(0.58±0.08)vs(0.47±0.04)vs(0.57±0.07)]与Cx43-Cq[(24.61±2.82)vs(22.18±2.62)vs(24.43±3.31)]差异均有统计学意义(P<0.05),中层心肌较心内膜与心外膜下心肌组织表达减少,表明家兔三层心肌间存在跨室壁Cx43表达的异质性。结论正常家兔中层心肌与心内外膜下心肌间存在Cx43蛋白表达不均一,这是左心室存在心肌横断面上复极离散的蛋白基础。
Objective To observe the change of transmural heterogeneity of connexin 43（Cx43） protein among three myocardial layers and explore physiological mechanisms of malignant ventricular arrhythmia（MVA）in normal rabbit. Methods 90% monophasic action potential repolarization duration(APD90), transmural dispersion of repolarization（TDR） and Cx43 protein（Cx43-pro） and m RNA（Cx43-Cq） expression among three myocardial layers were measured in normal rabbit. Results（1） APD90 was different among three myocardial layers in normal rabbit, and APD90 in the midmyocardium（233.80±19.37） was significantly prolonged than those in the subendocardium（201.20±18.72） and subepicardium（202.70±19.91）（P<0.05）, which showed that transmural dispersion of repolarization was existed among three myocardial layers.（2） Compared to those in the subendocardium and subepicardium,Cx43-pro [（0.58±0.08） vs（0.47±0.04） vs（0.57±0.07）] and Cx43-cq [（24.61±2.82） vs（22.18±2.62） vs（24.43±3.31）] expression in the midmyocardium was significantly decreased（P<0.05）, which indicated that there was transmural expression heterogeneity of Cx43 protein among three myocardial layers. Conclusion Transmural heterogeneity of Cx43 expression exists among three myocardial layers in rabbit, which may cause dispersion of repolarization.
出处
《海南医学》
CAS
2016年第4期517-519,共3页
Hainan Medical Journal
基金
国家自然科学基金(编号:81160024)
海南省自然科学基金(编号:814371)
