The Adrenal Glands

Each kidney has an adrenal gland located above it. The adrenal gland is divided into an inner medulla and
an outer cortex. The medulla synthesizes amine hormones, the cortex secretes steroid hormones. The
adrenal medulla consists of modified neurons that secrete two hormones: epinephrine and norepinephrine.
Stimulation of the cortex by the sympathetic nervous system causes release of hormones into the blood to
initiate the "fight or flight" response. The adrenal cortex produces several steroid hormones in three
classes: mineralocorticoids, glucocorticoids, and sex hormones. Mineralocorticoids maintain electrolyte
balance. Glucocorticoids produce a long-term, slow response to stress by raising blood glucose levels
through the breakdown of fats and proteins; they also suppress the immune response and inhibit the
inflammatory response.