Figure 3.

Steroid production by cultured two-layered secondary follicles. Levels of steroids secreted by follicles isolated from (A–D) mice of different ages and weights and from (E–H) D49 mice at different stages of the estrous cycle are shown. The steroid hormone profiles include E₂ (A and E), androstenedione (B and F) and progesterone (C and G) levels. In addition, the androgen/estrogen ratio is shown (D and H). Terminal E₂, androstenedione and progesterone levels were significantly higher in follicles isolated from D49 compared with those isolated from D100 and D270 mice (P<0.001, P<0.05, P<0.05; denoted by *). Follicles from D100* mice also secreted significantly higher E₂ and androstenedione levels compared with those isolated from D100 mice (P<0.0001, P<0.05; denoted by **). The androgen/estrogen ratio was significantly increased in follicles isolated from D100* mice (P<0.0001; denoted by **). Follicles isolated during estrus produced significantly higher E₂ levels compared with those isolated at diestrus (P<0.05; denoted by ***). Progesterone levels were also higher in follicles isolated in metestrus and estrus compared with those isolated in diestrus (P<0.05 comparing metestrus and estrus with diestrus; denoted by***).