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目的 探讨转化生长因子受体TGF-βRⅠ、TGF-βRⅡ在小鼠胚胎心流出道的时空表达规律以及与流出道发育的关系. 方法 9～14d小鼠胚胎连续切片,免疫组织化学PAP法染色. 结果 TGF-βRⅠ和TGF-βRⅡ在流出道心肌的表达开始于胚胎发育10d,11d延伸至流出道和心包腔背侧壁脏壁中胚层上皮的反折处,12d达高峰,同时于流出道心内膜垫可见TGF-βRⅡ阳性间充质细胞,13d后,两者表达均迅速减弱,14d表达降至最低. 结论 TGF-βRⅠ和TGF-βRⅡ在流出道表达集中于胚胎发育10～14d,TGF-βs信号系统可能参与调节心肌细胞的增殖、流出道的外形重建和内部分隔,并促进第二生心区间充质细胞分化为流出道远端平滑肌细胞.“,”Objective To investigate the spatiotemporal expression patterns of transforming growth factor-β(TGF-β) receptors type Ⅰ and type Ⅱ and their relationships with development of outflow tract(OFT) in mouse embryonic heart. Methods Serial sections of mouse embryos from embryonic day 9 (E9d) to embryonic day 14 (E14d) were stained using PAP immunohistochemical methods. Results Expressions of TGF-β receptors type Ⅰ (TGF-βRⅠ) and type II(TGF-βRⅡ) in the myocardial wall of OFT started at E10d, reached the reflection with splanchnic epithelium on the dorsal wall of the pericardial cavity at E11d. At E12d, expression intensity of TGF-βRⅠ and TGF-βRⅡ in myocardium increased to its highest level, and TGF-βRⅡ positive mesenchymal cells in OFT ridges could be detected. After E13d the staining intensity of TGF-βRⅠ and TGF-βRⅡ decreased rapidly,and at E14d,their expressions had fallen at the lowest.Conclusion The expressions of TGF-βRⅠ and TGF-βRⅡ in OFT are confined to the period of E10d to E14d, they may play important roles in regulating the myocardial cell proliferation, remodeling and septation of OFT, and promoting the differentiation from mesenchymal cells in the secondary heart field into smooth muscle cells in the distal end of OFT.