Fig. 4.

Hematoxylin-eosin (HE) stained postnatal mouse ovaries. Histological structures of the postnatal ovaries were analyzed herein. All follicles from primordial to antral follicles began to occur based on the time point of ovarian development, and corpus luteum formation was first observed in 5-week ovary onward. However, in the aged ovaries number of follicles and corpus luteum remarkably decreased, and many atretic follicles existed in these stages. PrF, Primordial follicle; PF, Primary follicle; SF, Secondary follicle; PAF, Preantral follicle; OF, Ovulated follicle; A, Atretic follicle; CL, Corpus luteum; CA, Corpus albicans; S, Stroma. The scale bar represents 50 μm