Pardanaud L, Luton D, Prigent M, Bourcheix L M, Catala M, Dieterlen-Lievre F
Institut d'Embryologie Cellulaire et Moleculaire du CNRS, Nogent-sur-Marne, France.
Development. 1996 May;122(5):1363-71. doi: 10.1242/dev.122.5.1363.
We have shown previously by means of quail/chick transplantations that external and visceral organs, i.e., somatopleural and splanchnopleural derivatives, acquire their endothelial network through different mechanisms, namely immigration (termed angiogenesis) versus in situ emergence of precursors (or vasculogenesis). We have traced the distribution of QH1-positive cells in chick hosts after replacement of the last somites by quail somites (orthotopic grafts) or lateral plate mesoderm (heterotopic grafts). The results lead to the conclusion that the embryo becomes vascularized by endothelial precursors from two distinct regions, splanchnopleural mesoderm and paraxial mesoderm. The territories respectively vascularized are complementary, precursors from the paraxial mesoderm occupy the body wall and kidney, i.e., they settle along with the other paraxial mesoderm derivatives and colonize the somatopleure. The precursors from the two origins have distinct recognition and potentialities properties: endothelial precursors of paraxial origin are barred from vascularizing visceral organs and from integrating into the floor of the aorta, and are never associated with hemopoiesis; splanchnopleural mesoderm grafted in the place of somites, gives off endothelial cells to body wall and kidney but also visceral organs. It gives rise to hemopoietic precursors in addition to endothelial cells.
我们之前通过鹌鹑/鸡移植实验表明，外部和内脏器官，即体壁层和脏壁层衍生物，通过不同机制获得其内皮网络，即通过迁移（称为血管生成）与前体细胞的原位出现（或血管发生）。我们追踪了用鹌鹑体节替代最后几个鸡体节（原位移植）或侧板中胚层（异位移植）后，鸡宿主中QH1阳性细胞的分布。结果得出结论，胚胎由来自两个不同区域的内皮前体细胞血管化，即脏壁层中胚层和轴旁中胚层。各自血管化的区域是互补的，轴旁中胚层的前体细胞占据体壁和肾脏，即它们与其他轴旁中胚层衍生物一起定居并在体壁层中定植。来自这两个起源的前体细胞具有不同的识别和潜能特性：轴旁起源的内皮前体细胞被阻止使内脏器官血管化并整合到主动脉底部，并且从不与造血相关；移植到体节位置的脏壁层中胚层不仅向体壁和肾脏释放内皮细胞，还向内脏器官释放。它除了产生内皮细胞外，还产生造血前体细胞。
