Corticotropin releasing hormone (CRH) is a neurohormone which stimulates the release of ACTH from the anterior pituitary.

Cortisol, produced by the adrenal cortex, feeds back on the pituitary to stimulate ACTH release.

ACTH release exhibits a diurnal rhythm related to the activity period shown by an individual.

Sympathetic fibers terminate on CRH neurons and stimulate CRH release.