3)心管壁 内膜心管→内皮 心胶质→内皮下层,心内膜下层 °心肌外套层→心肌膜,心外膜 Dorsal aorta nocardial Epimyocardial eural crest Intra- Foregut cavity Fusing mesocardium endocardial heart tubes Epimyocardium Cardiac 国下 B Endocardial3)心管壁 •心内膜心管→内皮 •心胶质→内皮下层，心内膜下层 •心肌外套层→心肌膜，心外膜