Hypothalamic stimulatory hormones
Function of Pituitary Hormones
|Corticotropin-releasing hormone (CRH)||Adrenocorticotropic hormone (ACTH) -ACTH is product of POMC gene||Stimulates the adrenal cortex to secrete glucocorticoids like cortisol|
|Melanocyte-stimulating hormone (MSH) – alternate product of POMC gene|
|Endorphins – also products of POMC gene|
|Growth hormone-releasing hormone||Growth hormone (GH)||Promotes movement of amino acids into cells and incorporation of these amino acids into proteins, promoting overall tissue and organ growth. Also, promotes the growth of cartilage and bone.|
|Gonadotropin-releasing hormone (GnRH)||Follicle-stimulating hormone (FSH) and||In Females: Stimulates growth/development of the ovarian follicles|
|In Males: Stimulates testicular growth and production of sperm|
|Luteinizing hormone (LH)||In women, a surge of LH in the mid-menstrual cycle stimulates ovulation and continued LH secretion subsequently stimulates conversion of the ovulated ovarian follicles into the corpus luteum which produces progesterone. LH also stimulates estrogen and progesterone production from the ovary.|
|In men, LH stimulates testosterone production from the interstitial cells of the testes (Leydig cells).|
|Thyrotropin-releasing hormone (TRH)||Thyroid-stimulating hormone (TSH)||Stimulates thyroid gland to make T4 and T3|
|Prolactin-releasing factors – include serotonin, acetylcholine, opiates, and estrogens||Prolactin||Stimulates milk production in the mammary glands.|
Hypothalamic inhibitory hormones
|Somatostatin||Inhibits the release of growth hormone|
|Prolactin-inhibiting factors – includes dopamine||Major prolactin control is inhibitory|
FSH and LH secretion are affected by a negative feedback from sex steroids. Inhibin also has a negative feedback on FSH selectively. High-dose testosterone or estrogen therapy suppresses FSH and LH. Primary gonadal failure in men and women leads to high levels of FSH and LH, except in selective destruction of testicular tubules with subsequent elevation of only FSH, as in Sertoli-cell-only syndrome. Similarly, any process leading to a low FSH level also simultaneously results in a low LH level, except in rare instances of isolated FSH deficiency or isolated LH deficiency in fertile eunuch syndrome.
FLAG-TOP – Anterior Pituitary Hormones
F: Follicle Stimulating Hormone (FSH)
L: Luteinizing Hormone (LH)
G: Growth Hormone (GH)
T: Thyroid Stimulating Hormone (TSH)
O: MSH – melanOcyte stimulating hormone
The posterior pituitary – Stores and releases hormones produced by the hypothalamus.
The anterior pituitary – Produces and releases its own hormones (under the regulation of hormones made by the hypothalamus).
Posterior pituitary Hormones
These are made in the hypothalamus and stored in the posterior pituitary.
Evaluation of the menstrual cycle and timing of ovulation, Uptodate.com