Glomerular capillary formation is one of the fundamental mysteries in renal developmental biology. However, there are still debates on this issue, and its detailed formation process has not been clarified. To resolve this problem, we performed antibody staining with ultra-thick section on embryonic and postnatal mouse kidneys. We obtained the expression patterns of several genes that play an important role in the development of glomerular capillaries. We found that blood vessel of the fetal kidneys expanded through proliferation and sprouting. During the comma-stage and S-shaped stage, 3–4 capillaries began to bud and migrate into the glomerular cleft, forming a capillary bed in the Bowman's capsule. Then, the capillary bed expanded into mature glomerular capillary by intussusceptive angiogenesis. The afferent and efferent arterioles were formed through pruning. The distribution of VEGFA in the nephron epithelial cells but not only in podocytes, induced multiple capillaries sprouted into the glomerular cleft. And CXCR4 played an important role in the differentiation and expansion of capillary bed into glomerular capillary. Immunofluorescence performed with ultra-thick section allowed us to investigate the development of complex structure tissues systematically and comprehensively.

肾小球毛细血管的形成是肾脏发育生物学的基本谜团之一。但是，关于该问题仍存在争议，其详细形成过程尚未阐明。为了解决这个问题，我们对胚胎和出生后的小鼠肾脏进行了超厚切片的抗体染色。我们获得了在肾小球毛细血管发展中起重要作用的几个基因的表达模式。我们发现胎儿肾脏的血管通过增殖和发芽而膨胀。在逗号期和S形期，3–4个毛细血管开始萌芽并迁移到肾小球裂隙中，在Bowman囊中形成了毛细血管床。然后，通过肠套叠血管生成，毛细血管床扩展为成熟的肾小球毛细血管。通过修剪形成传入和传出的小动脉。VEGFA在肾上皮细胞中的分布，不仅在足细胞中，还引起多个毛细血管发芽进入肾小球裂隙。CXCR4在毛细血管床分化和扩张为肾小球毛细血管中起着重要作用。超厚切片的免疫荧光技术使我们能够系统地，全面地研究复杂结构组织的发展。