Adrenal Insufficiency

The hypothalamic–pituitary–adrenal axis has an important role in the body's ability to cope with stresses such as infections, hypotension, and surgery. The hypothalamus is subject to regulatory influences from other parts of the brain, especially the limbic system. The hypothalamic hormones corticotropin-releasing hormone and arginine vasopressin are important stimulants of corticotropin secretion by the anterior pituitary. In this gland, the action of the hypothalamic hormones is amplified so that a much larger number of corticotropin molecules is secreted. Similarly, in the adrenal cortex the action of corticotropin is amplified; a plasma corticotropin concentration of approximately 25 pg per milliliter (5.5 . . .