Adrenal Glands are located one above each kidney.
The adrenal gland is divided into an inner medula and an outer cortex. The medulla synthesizes 2 hormones, epinephrine (adrenaline) and norepinephrine. When the sympathetic nervous system stimulates the cortex causes hormones related to fight-or-flight to get secreted into the blood. The adrenal cortex produces several steroid hormones in 3 classes: mineralocorticoids (maintain electrolyte balance), glucocorticoids (long-term, slow response to stress by raising blood glucose levels by breaking down fats and proteins, and also suppress immune system and inhibit inflammatory response), and corticosteroids such as cortisone (which are anti-inflammatory hormones suppressing secretion, and suppress immune system.
In response to ACTH from the pituitary gland, the adrenal cortex makes adrenocorticoids including:
- Glucocorticoids, like cortisol, increase blood glucose, cause protein breakdown, and are anti-inflammatory.
- Mineralocorticoids, specifically aldosterone, which acts on kidneys to retain sodium and conserve water.
- Sex steroids, specifically androstenedione.
The adrenal medulla secretes epinephrine (adrenaline) and norepinephrine in response to sympathetic activity from the hypothalamus.