Hypoplastic and cystic kidneys in Lrp6-KO mouse embryos. (A–C, E–G) Hematoxylin and eosin (HE) staining shows the mesonephros at E10.5 and E11.5, and the metanephros at E18.5 of WT and mutant embryos. (D, H) Whole renal structures of the normal and mutant embryos at E18.5. Ad, adrenal gland; Glu, glomerulus; Ki, kidney; MD/MT, mesonephric duct/tubules; asterisk, cysts.