压力超负荷时心肌闰盘的改变

Change of intercalated discs of myocardium induced by pressure overload

目的 研究压力超负荷时心肌闰盘的变化。方法 采用大鼠腹主动脉缩窄模型 ,在透射电镜下观察心肌闰盘的超微结构变化 ;免疫组化观察钙粘素 (pan cadherin) ,连接蛋白 43(connexin43,Cx43) ,桥粒蛋白 (desmoplakin)的表达。结果 术后 10周手术组心肌闰盘的粘着膜、桥粒、间隙连接结构模糊 ,连接间隙增宽 ;Pan cadherin ,Cx43,desmoplakin在心肌细胞表面呈无序分布。结论 压力超负荷时心肌闰盘的主要结构及其成分均发生了改变 ,这可能是左室重塑的病理基础之一。

Objective To investigate the change of intercalated discs induced by pressure overload. Methods The model of rat abdominal aortic constriction was adopted. Ultrastructures of the intercalated discs were observed by electron microscopy. Expression of pan cadherin, connexin 43 (Cx43) and desmoplakin in the cardiomyocytes were studied by immunohistochemical technique. Results At the 10th week after constriction, the structure of cadherin, desmosome and gap junction in intercalated discs were destroyed, gap of intercellular space widened. Pan cadherin, Cx43 and desmoplakin distributed disorderly on the surface of cardiomyocytes. Conclusion The results indicate that the structure of intercalated discs and its components are changed during left ventricular pressure overload, and it might be one of the pathological basis of left ventricular remodeling.