成人房室交界区过渡细胞束形态学及连接蛋白43和40的表达

目的 观察临床上心律失常常见发生部位及射频消融治疗靶点部位--房室交界区和邻近区域的形态学特点及连接蛋白(Cx)43和40的表达,为心律失常发生机制及可能的有效治疗部位提供形态学依据.方法 10例正常成人心脏,选取房室交界区及其邻近部位,常规石蜡包埋,HE、Masson染色,选定目标部位行Cx43、Cx40免疫组织化学...

Morphology and the expression of connexin 43 and 40 in bundles of transition cells in the adult atrioventricular junction

Objective To observe the morphological feature and the expression of connexin(Cx)43 and Cx40 in the common arrhythmogenesis and radiofrequency ablation(RFA) region, the atrioventricular junction and its surrounding area, in order to provide the morphological basis for understanding the mechanism of arrhythmogenesis and possible sites for therapy. Methods Ten fresh normal adult hearts were used in this study. The specimens containing the atrioventricular node(AVN) was harvested, embedded in paraffin and sectioned. The sections were stained with HE, Masson staining. Expression of Cx43 and Cx40 was examined by immunohistochemistry and image analysis. Results There were the bundles of transition cells at cavo tricuspid isthmus, around the opening and distal end of coronary sinus, at the annulus fibrosus of bicuspid valve, and at the central fibrous body(CFB) near the annulus of right atrium upper-valve muscles. The bundles connected between the AVN and posterior node extension(PNE) in different directions. The transition cells were different from ordinary cardial muscle cells in the cell component, assignment, course and association of fibers. The distribution of Cx43 and Cx40 in bundles1 4 of transition cells and annulus of right atrium upper vavle muscles was limited in a small area. Expression of Cx43 and 40 was widely present in the transition cells of left atrium close to the membranous part of interventricular septum and extensively localized at cavo-tricuspid isthmus. Conclusion Dual atrioventricular(AV) nodal pathways(DAVNP) and multiple AV nodal pathways(TAVNP) are at and nearby the atrioventricular junction. And they are coherent with the target spots using in radiofrequency ablation to treat arrhythmia, which may indicate a new potential radiofrequency ablation site wher