Management of Patients With Adrenal Disorders

Management of Patients With Adrenal Disorders

There are two adrenal glands in the human, each attached to the upper portion of a kidney. Each adrenal gland is, in reality, two endocrine glands with separate, independent functions. The adrenal medulla at the center of the gland secretes catechol-amines, and the outer portion of the gland, the adrenal cortex, secretes steroid hormones (Fig. 42-6). The secretion of hormones from the adrenal cortex is regulated by the hypothalamic-pituitary-adrenal axis. The hypothalamus secretes corticotropin-releasing hormone (CRH), which in turn stimulates the pituitary gland to secrete ACTH. ACTH then stimulates the adrenal cor-tex to secrete glucocorticoid hormone (cortisol). Increased levels of the adrenal hormone then inhibit the production or secretion of CRH and ACTH. This system is an example of a negative feedback mechanism.