Figure 2.

VIP promoted the transformation from primordial follicles to early growing follicles in neonatal rat ovary. Four-day-old rat ovaries were cultured in basal medium without VIP (control group) or with VIP in different concentrations for three days. (A) The representative photos of all groups stained with hematoxylin and eosin: control (a), 10⁻⁶ mol/L (b), 10⁻⁷ mol/L (c), 10⁻⁸ mol/L (d). (B) and (C) The numbers of early-growing follicles and primordial follicles were counted, and their ratio was calculated. Scale bar: 50 μm. Values are mean ± s.d. of at least three experiments. (*P < 0.05 compared with the VIP⁻⁶ mol/L group, ^& P < 0.05 compared with the VIP⁻⁷ mol/L group, ^# P < 0.05 compared with the VIP⁻⁸ mol/L group).