Major hypothalamic hormones and their effect on anterior pituitary hormones

Hypothalamic stimulatory hormones	Pituitary hormones
Corticotropin-releasing hormone - 41 amino acids; released from paraventricular neurons as well as supraoptic and arcuate nuclei and limbic system	Corticotropin - basophilic corticotrophs represent 20% of cells in anterior pituitary; ACTH is product of POMC gene.
	Melanocyte-stimulating hormone - alternate product of POMC gene
	Endorphins - also products of POMC gene
Growth hormone-releasing hormone - two forms, 40 and 44 amino acids	Growth hormone - acidophilic somatotrophs represent 50% of cells in anterior pituitary
Gonadotropin-releasing hormone - 10 amino acids; mostly released from preoptic neurons	Luteinizing hormone and follicle-stimulating hormone - gonadotrophs represent approximately 15% of anterior pituitary cells
Thyrotropin-releasing hormone - three amino acids; released from anterior hypothalamic area	Thyroid-stimulating hormone - thyrotropes represent approximately 5% of anterior pituitary cells
Prolactin-releasing factors - include serotonin, acetylcholine, opiates, and estrogens	Prolactin - lactotrophs represent 10 to 30% of anterior pituitary cells
Hypothalamic inhibitory hormones
Somatostatin - 14 amino acids	Inhibits the release of growth hormone
Prolactin-inhibiting factors - includes dopamine	Major prolactin control is inhibitory

ACTH: corticotropin; POMC: proopiomelanocortin.

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