目的　探讨成人与新生儿心脏连接蛋白 4 3(Cx4 3)表达差异。　方法　应用SP免疫组织化学和图像分析方法 ,观测成人与新生儿心脏Cx4 3的蛋白表达。　结果　 1 新生儿心脏Cx4 3在心房和心室均呈斑点状遍布于心肌细胞侧面连接处和细胞质内 ,闰盘处极少。 2 成人Cx4 3表达在心房肌非均质分布于细胞侧面连接处和端闰盘处 ;心室肌典型地排列在闰盘处。 3 图像分析表明 ,心肌细胞Cx4 3分布密度 ,新生儿心房 <心室 ,成人心房 >心室。成人心房、心室均低于新生儿。　结论　新生儿Cx4 3主要分布于心肌细胞侧连接处 ,成人心房和心室存在差异。Cx4 3分布密度新生儿心房 <心室 ,成人心房 >心室 ;成人心脏低于新生儿。提示 ,Cx4 3有增龄变化。 Objective To investigate the expression differences of Cx43 between adult and newborn. Methods SP immunohistochemistry and image analysis were used to observe the expression of Cx43 protein in adult and neonatal hearts. Results 1 neonatal heart Cx4 3 were spotted in the atrium and ventricle throughout the cardiomyocyte side junctions and cytoplasm, rarely intercalated disk. 2 Adult Cx4 3 expression is heterogeneously distributed in the atrial muscle at the cell lateral junctions and at the terminal intercalation disc; ventricular muscles are typically arranged at the intercalated disc. 3 image analysis showed that the density of Cx4 3 myocardial cells, neonatal atrial ventricular. Adult atria, ventricular were lower than the newborn. Conclusion Newborn Cx4 3 is mainly distributed in the junction of myocardial cells, there is a difference between adult atria and ventricles. Cx4 3 Distribution Density Neonatal atrial ventricular; adult heart lower than newborn. Tip, Cx4 3 have aging changes.