犬陈旧性心肌梗死时连接蛋白43的分布  

Distribution of Gap Junctional Connexin 43 in Canine with Chronic Myocardial Infarction

作　　者：霍明章[1] 于德洁[1] 郝维[1] 陈孟勤[1] 曹济民[1] 

机构地区：[1]中国医学科学院中国协和医科大学基础医学研究所生理学研究室,北京100005

出　　处：《中国医学科学院学报》2001年第3期255-258,I003,共5页Acta Academiae Medicinae Sinicae

基　　金：家自然科学基金(39970300)资助&&

摘　　要：目的 探讨陈旧性心肌梗死时心肌缝隙连接蛋白43（connexin 43, Cx43）的分布特征。方法结扎犬冠状动脉造成心肌梗死，术后恢复40～50 d。用改良的免疫细胞化学法显示心肌梗死区、边缘带及非缺血区Cx43的分布，半定量分析不同部位Cx43的分布密度。结果与正常心肌相比，梗死病灶及其邻近区域Cx43的分布出现明显紊乱：梗死中心区Cx43完全消失；边缘带Cx43呈现不均匀消失，少量Cx43分布于岛状或半岛状尚存活的心肌；心肌细胞端－端相接处的Cx43严重消失，而细胞侧－侧相接处的Cx43仍有部分存在。非缺血区Cx43的密度和分布与正常心肌相比无明显改变。结论陈旧性心肌梗死时Cx43的数量和分布呈现高度不均一性，尤其在边缘带Cx43的分布特点是形成局部传导阻滞和折返性心律失常的结构基础。Objective To characterize the distribution pattern of gap junctional connexin 43 (Cx43) in canine with chronic myocardial infarction. Methods Left anterior descending coronary arteries were ligated to create myocardial infarction and the dogs were allowed to recover for 40～50 days. Cx43 was visualized with a modified immunocytochemical method and was semi-quantitatively analyzed in different regions. Results The distribution of Cx43 gap junctions was markedly disturbed in the scar and adjacent regions compared with the non-ischemic regions. Cx43 was not found in the necrotic zone and inhomogeneously lost in the border zone, with a few Cx43 labeling gap junctions distributed in the island-or peninsula-like regions of surviving myocardium. In regions of the border zone near the non-ischemic regions, the transversely oriented Cx43 gap junctions were lost much more seriously than the longitudinally oriented ones. There were no significant changes in Cx43 density or distribution pattern in non-ischemic regions compared with normal myocardium. Conclusion There were marked inhomogeneities in distribution and density of Cx43 gap junctions in hearts with chronic myocardial infarction, especially in the border zone. These Cx43 distribution patterns form the anatomical basis for conduction block and reentry arrhythmias.

关 键 词：缝隙连接 连接蛋白43 折返性心律失常 陈旧性心肌梗死 

分 类 号：R542.22[医药卫生—心血管疾病] R541.7[医药卫生—内科学]