Corticotropin, also known as ACTH or adrenocorticotropic hormone, is a peptide tropic hormone synthesized by the anterior pituitary gland in response to the release of corticotropin-releasing hormone (CRH) from the hypothalamus. It is produced from the cleavage of pre-pro-opiomelanocortin by various endopeptidases, along with other physiologically active peptide fragments such as β-lipotropin, γ-lipotropin, melanocyte-stimulating hormone (MSH), and β-endorphin. As an essential component of the hypothalamic-pituitary-adrenal axis, corticotropin is primarily responsible for increasing the adrenal cortex production of cortisol in response to stress. The ACTH receptor activates G(s) proteins which lead to the activation of adenylyl cyclase which produces the secondary messenger cAMP. cAMP activates pKA (protein kinase A) which phosphorylates downstream effectors that lead to androgen and cortisol production.

Corticotropin Activation of Cortisol Production References