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Unformatted text preview: Learning Issue: Female Hormones-MH The ovaries, analogues to the testes in the male, have two functions: oogenesis and secretion of the female sex steroid hormones, progesterone and estrogen. Gonadotropin-releasing hormone (GnRH)- is delivered directly to the anterior lobe of the pituitary in high concentration, where it stimulates pulsatile secretion of FSH and LH (i.e. drives ovarian function) Follicle stimulating hormone (FSH)- The granulosa cells are the only ovarian cells with FSH receptors. Initial actions of FSH stimulate the growth of granulosa cells in primary follicles and stimulate estradiol synthesis. The locally produced estradiol synthesis then supports the trophic effect of FSH on follicular cells. Therefore, the two effects of FSH on granluosa cells are mutually reinforcing more cells, more estradiol, and more cells. Luteinizing hormone (LH )- Ovulation is initiated by LH. Just prior to ovulation, the concentration of LH in the blood rises sharply and induces rupture of the dominant follicle,...
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- Fall '10
- progesterone, corpus luteum, Luteinizing hormone, estrogen, Granulosa Cells