Control of TSH: Secretion of TSH is controlled by:
Thyrotropin-Releasing Hormone (TRH) There is NO inhibiting hormone.
Release of TRH depends on blood levels of T3 and T4 through negative feedback system.
3) Gonadotrophs
Secrete 2 gonadotropins:
Follicle-Stimulating Hormone (FSH) Luteinizing Hormone (LH).
Function of FSH and LH :
Both act on the gonads that stimulate estrogens and progesterone; maturation of oocytes in the ovaries, triggers ovulation; the production of sperm and secretion of testosterone in the testes.
Control of FSH & LH:
Secretion of FSH & LH is controlled by:
Gonadotropin-Releasing Hormone (GnRH) NO inhibiting hormone
Release of GnRH is suppressed by estrogens in females and testosterone in males through negative feedback.
4) Lactotrophs
Secrete Prolactin (PRL)
Function of PRL:
Initiates milk production in the mammary glands. The function of prolactin in males is not known but excess causes erectile dysfunction
Control of PRL:
Secretion of PRL is controlled by:
Prolactin-Releasing Hormone (RRH) Prolactin-Inhibiting Hormone (PIH) (dopamine) PRH is only released during pregnancy and after birth to stimulate milk production.
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