Merriam-Webster Online Dictionary
adrenocorticotropin (noun)
- acth
adrenocorticotropin (Wikipedia)
This article is about adrenocorticotropic hormone as a natural hormone. For adrenocorticotropic hormone as a medication and diagnostic agent, see Adrenocorticotropic hormone (medication).
Symbol OMC
Entrez 5443
HUGO 9201
OMIM 176830
RefSeq NM_000939
UniProt P01189
Other data
Locus Chr. 2 p23

Adrenocorticotropic hormone (ACTH), also known as corticotropin is a polypeptide tropic hormone produced and secreted by the anterior pituitary gland. It is also used as a medication and diagnostic agent.

It is an important component of the hypothalamic-pituitary-adrenal axis and is often produced in response to biological stress (along with its precursor corticotropin-releasing hormone from the hypothalamus). Its principal effects are increased production and release of cortisol by the cortex of the adrenal gland. ACTH is also related to the circadian rhythm in many organisms.

Deficiency of ACTH is a sign of secondary adrenal insufficiency (suppressed production of ACTH due to a impairment of the pituitary gland or hypothalamus, cf. hypopituitarism) or tertiary adrenal insufficiency (disease of the hypothalamus, with a decrease in the release of corticotropin releasing hormone CRH). Conversely, chronically elevated ACTH levels occur in primary adrenal insufficiency (e.g. Addison's disease) when adrenal gland production of cortisol is chronically deficient. In Cushing's disease a pituitary tumor is the cause of elevated ACTH (from the anterior pituitary) and an excess of cortisol (hypercortisolism) – this constellation of signs and symptoms is known as Cushing's syndrome.