Fig. 1.

Defective uterine receptivity in N1ICD OEx mice. (A) No implantation sites (ISs) are detected in N1ICD OEx mice at 3.5 dpc, whereas control, OEx + KO, and Rbpj KO mice have normal numbers of ISs. The number of ISs (n = 3 of each group) is shown in the histogram. (B) The right uterine horns, which received WT embryos, have ISs in control mice but not in OEx mice, whereas the left horns served as controls without embryo transfer. Histological staining shows an implanted blastocyst with decidualized stromal cells surrounding it in control mice and a free-floating blastocyst in uterine lumen without decidualization in OEx mice. (C) Artificial decidualization stimulus induces a decidual response in control mice vs. no decidualization response in OEx mice. Histological staining shows cross-sections of stimulated horns (right horns) in both two groups. Left horns are nonstimulated controls. (D) Weight of stimulated horns in control mice is >20 times higher than that of nonstimulated horns in control mice, but there is no difference between stimulated and nonstimulated horns of OEx mice (n = 4 of each group). Decidualization markers (E) Bmp2 and (F) Wnt4 are significantly increased in the stimulated horns of control mice, whereas no significant induction is evident in OEx mice (n = 4 of each group). B, blastocyst; Ctrl, control; Dec, decidua; LE, luminal epithelium; St, stroma. *P < 0.05; **P < 0.01.