hypothalamusandpituitary
Image from Uptodate.com

Image from Uptodate.com

hypothalamus-and-pituitary

Hypothalamic stimulatory hormones

Pituitary 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
ACTH: adrenocorticotropic hormone; POMC: proopiomelanocortin.
FSH and LH bind to receptors in the testis and ovary and regulate gonadal function by promoting sex steroid production and gametogenesis.

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

“FLAG-TOP”
F: Follicle Stimulating Hormone (FSH)
L: Luteinizing Hormone (LH)
A: ACTH
G: Growth Hormone (GH)
T: Thyroid Stimulating Hormone (TSH)
O: MSH – melanOcyte stimulating hormone
P: Prolactin

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.

ADH
Oxytocin

 

References

https://www.khanacademy.org/science/health-and-medicine/human-anatomy-and-physiology/reproductive-system-introduction/v/reproductive-cycle-graph-follicular-phase

Evaluation of the menstrual cycle and timing of ovulation, Uptodate.com
http://www.uptodate.com/contents/hypothalamic-pituitary-axis
https://www.khanacademy.org/science/health-and-medicine/endocrine%20system/Endocrine-system-introduction%20/v/hypothalamus-and-pituitary-gland

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