Figure 4.

Leptin’s role in ovarian follicular and oocyte maturation. All ovarian follicular cells have leptin receptors and physiological levels of leptin stimulate granulosa and theca cells and oocyte maturation. This drawing is based on many studies showing leptin stimulation of these target cells. Physiological levels of leptin stimulates, in partnership with growth factors (IGF-1), GH, and FSH, to promote the development of follicles to the antral stage. Leptin also promotes ovulation and oocyte maturation in partnership with LH. Leptin levels rise in association with rising estradiol from the follicles (granulosa cells). Leptin also acts with LH and growth factors to promote oocyte meiosis and formation of the polar body.