Chapter 27 Reproductive System: Hormones of the Reproductive System
What do androgens do?
Establish and maintain secondary sex characteristics and sexual behavior; promote maturation of spermatozoa; and inhibit gonadotropin releasing hormone (GnRH) secretion
What do progestins do?
Stimulate endometrial growth and glandular secretion; reduce frequency of gonadotropin releasing hormone (GnRH) pulses
What do estrogens do?
Stimulate luteinizing hormone (LH) secretion (at high levels); establish and maintain secondary sex characteristics and sexual behavior; stimulate repair and growth of endometrium; increase frequencies of gonadotropin releasing hormone (GnRH) pulses
What regulates luteinizing hormone (LH) in males?
Stimulated by gonadotropin releasing hormone (GnRH)
What is the source of follicle stimulating hormone (FSH)?
anterior lobe of pituitary gland
What is the source of luteinizing hormone (LH)?
anterior lobe of pituitary gland
What does follicle stimulating hormone (FSH) do in females?
stimulates follicle development, estrogen production, and oocyte maturation
What does the luteinizing hormone (LH) do in males?
stimulates interstitial cells to secrete testosterone
What does the luteinizing hormone (LH) do in females?
stimulates ovulation, formation or corpus luteum, and progestin secretion
What does follicle stimulating hormone (FSH) do in males?
stimulates spermatogenesis and spermiogensis through effects on sustentacular cells
What is the source of inhibin?
sustentacular cells of testes and granulosa cells of ovaries
What inhibits gonadotropin releasing hormone in males?
testosterone and possibly inhibin
What regulates follicle stimulating hormone (FSH) in both males and females?
stimulated by gonadotropin releasing hormone (GnRH) inhibited by inhibin
What is inhibin secretion stimulated by?
factors released by developing spermatozoa (males) and developing follicles (females)
What is estrogen secretion stimulated by?
follicle stimulating hormone (FSH)
What is the source of estrogens?
granulosa and thecal cells of developing follicles; corpus luteum
What is the source of progestins?
granulosa cells from mid life cycle through functional life of corpus luteum
What is the source of gonadotropin releasing hormone?
hypothalamus
What regulates gonadotropin releasing hormone in females?
increased by estrogens decreased by progestins
What does inhibin do?
inhibits secretion of follicle stimulating hormone (FSH) and possibly gonadotropin releasing hormone (GnRH)
What is the source of androgens?
interstitial cells of testes
What is androgen secretion stimulated by?
luteinizing hormone (LH)
What is progestin secretion stimulated by?
luteinizing hormone (LH)
What regulates luteinizing hormone (LH) in females?
production stimulated by gonadotropin releasing hormone (GnRH), secretion by the combination of high gonadotropin releasing hormone (GnRH) frequencies and high estrogen levels
What does gonadotropin releasing hormone (GnRH) do in both males and females?
promotes secretion of FSH and LH production
