Hypothalamic-Pituitary-Adrenal Axis

The Hypothalamic-Pituitary-Adrenal (HPA) Axis serves as the primary control center for cortisol production. As outlined below and seen in Figures A, B & C, various triggers can throw the system off balance and create an excess of cortisol in the body.

A:   Adrenal tumor: excess cortisol is released, suppressing (decreasing) Adrenocorticotropic Hormone (ACTH)

B:   Pituitary tumor: increased ACTH production leads to overstimulation of adrenal glands and increased production of cortisol

C:   Tumor elsewhere in the body that produces ACTH leads to overstimulation of adrenal glands and increased production of cortisol