Central hormone of the hypothalamic–pituitary–adrenal (HPA) axis.
Also known as: Adrenocorticotropic hormone · Corticotropin
Part of the Foundational & therapeutic peptides cluster
Overview
ACTH (adrenocorticotropic hormone) is a 39-amino-acid pituitary hormone that drives adrenal cortisol release. As a key node of the HPA stress axis, it is a foundational peptide in endocrinology.
Source & context
Biological / chemical source: Anterior pituitary; derived from proopiomelanocortin (POMC)
Primary research or clinical context: Endocrine diagnostics and research (approved forms exist)
HPA-axis role
ACTH is released in response to hypothalamic CRH and stimulates the adrenal cortex to produce cortisol. Its first 24 residues carry the biological activity, a fact reflected in synthetic fragments used in endocrine testing.
Shared POMC origin
ACTH is cleaved from proopiomelanocortin, the same precursor that yields alpha-MSH and beta-endorphin. This shared origin explains overlapping sequence motifs across these peptides.
Sequence
One-letter sequence commonly cited for ACTH (educational; isoforms and modifications may differ):
SYSMEHFRWGKPVGKKRRPVKVYPNGAEDESAEAFPLEF
Residues plotted ~100° apart around an α-helix — clustering of one color reveals an amphipathic face.
FAQ about ACTH
What is ACTH?+
ACTH (adrenocorticotropic hormone) is a 39-amino-acid pituitary hormone that drives adrenal cortisol release. As a key node of the HPA stress axis, it is a foundational peptide in endocrinology.
Is ACTH an approved medicine?+
ACTH is discussed here as a research / educational topic. Endocrine diagnostics and research (approved forms exist). This is not medical advice.
What is the typical length of ACTH?+
ACTH is commonly described as approximately 39 amino acids (Hormone).