Research Paper Volume 12, Issue 8 pp 7313—7333

Estrogen regulation of germline stem cell differentiation as a mechanism contributing to female reproductive aging

Figure 3. Estrogen enhances ovarian Stra8 expression and oogenesis in vivo. (A) Changes in Stra8 mRNA levels in ovaries of young adult WT mice 24 hours after injection of vehicle (V), E2 (0.5 mg/kg), P4 (100 mg/kg) or E2 plus P4 (mean ± SEM, n = 3 mice per group; *P<0.05). (B) Yield of GFP-positive germ cells from ovaries of young adult pStra8-GFP mice 24 hours after injection of V or E2 (0.5 mg/kg) (mean ± SEM, n = 3 mice per group; *P<0.05). (CF) Numbers of primordial (C), recently growth-activated (primary; D) and early growing (small-preantral; E) follicles, and of degenerative oocytes (F), in ovaries of young adult WT mice 24 hours after injection of V, E2 (0.5 mg/kg), P4 (100 mg/kg) or E2 plus P4 (mean ± SEM, n = 8–10 mice per group; *P<0.05). (G) Primordial follicle numbers in ovaries of reproductively aged (8-month-old) WT mice 24 hours after injection of V or E2 (0.5 mg/kg) (mean ± SEM, n = 3 mice per group; *P<0.05). (H, I) Changes in Stra8 mRNA levels (H) and primordial follicle numbers (I) in ovaries of young adult WT mice 46 hours after injection of PMSG (10 IU) followed by hCG injection (10 IU) 16 hours later (mean ± SEM, n = 5–7 mice per group; *P<0.05).