Polypeptide hormone made in the pituitary gland. It regulates the activity of part of the adrenal cortex (see adrenal glands), the production site of important steroid hormones that affect electrolyte and water balance and the metabolism of fats, carbohydrates, and proteins. ACTH is found in vertebrates (except jawless fishes); in mammals it contains 39 amino acids. Overproduction of ACTH is one cause of Cushing syndrome.
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Adrenocorticotropic hormone (ACTH or corticotropin) is a polypeptide hormone produced and secreted by the pituitary gland. It is an important component of the hypothalamic-pituitary-adrenal axis and is often produced in response to biological stress (along with corticotropin-releasing hormone). Its principal effects are increased production of androgens and, as its name suggests, cortisol.
After a short period of time, ACTH is cleaved into α-melanocyte-stimulating hormone (α-MSH) and CLIP, a peptide with unknown activity in humans.
ACTH is also related to the circadian rhythm in many organisms.
The half-life of ACTH in human blood is about ten minutes.
ACTH was first synthesized as a replacement for Acthar Gel, a long-lasting animal product. Once relatively inexpensive, it is currently an extremely expensive pharmaceutical product. Prices per vial have been as high as $25,000.