小鼠胚胎心流出道心内膜垫的形成与融合

The formation and fusion of the endocardial cushion of the outflow tract in mouse embryonic heart

目的观察不同发育时期小鼠胚胎心流出道心内膜垫的发育过程。方法对胚龄9-12d小鼠胚胎心脏连续切片进行HE染色和免疫组化染色。结果胚龄10d,流出道远端心胶质内开始观察到间充质细胞。胚龄11d,两侧流出道心内膜垫形成,心内膜垫内部分间充质细胞染色呈α-平滑肌肌动蛋白(α-SMA)阳性。胚龄12d,两侧流出道心内膜垫内部分间充质细胞聚集形成致密漩涡状结构,随着心内膜垫融合,两侧漩涡状结构融合。结论小鼠胚胎流出道心内膜垫形成于胚胎发育第11天,第12天融合,间充质细胞参与心内膜垫融合。

Objective To investigate the development of the endocardial cushion of the outflow tract of mouse embryonic heart. Methods Serial sections of mouse embryonic hearts from embryonic day 9 （ED9） to embryonic day 12 （ED12） were stained with HE and immlmohistochemistry staining. Results At ED10, the mesenchymal cells were observed in the cardiac jelly of the outflow tract. At ED11, the outflow tract cushion formed and part of the mesenchymal cells in the cushion expressed α-smooth muscle actin（α-SMA ） positively. At ED12, part of the mesenchymal cells in the cushions were aggregated to form condense cellular whorl. With the fusion of the outflow tract cushion, the bilateral condensed cellular whorls also fused to form one whorl. Contusion The formation of the outflow tract cushion is at ED11, and the fusion of the cushion is at ED12 in mouse embryonic heart, the mesenchymal cells is involved in the cushion fusion.