Adrenal Gland - Anatomy and Physiology

Anatomy and Physiology

The adrenal glands are located in the retroperitoneum superior to the kidneys, they are triangular in shape and are situated bilaterally. The combined weight of the adrenal glands in an adult human ranges from 7 to 10 grams. They are surrounded by an adipose capsule and renal fascia.

Each adrenal gland has two distinct structures, the outer adrenal cortex and the inner medulla, both of which produce hormones. The cortex mainly produces cortisol, aldosterone and androgens, while the medulla chiefly produces epinephrine and norepinephrine. In contrast to the direct innervation of the medulla, the cortex is regulated by neuroendocrine hormones secreted from the pituitary gland which are under the control of the hypothalamus, as well as by the renin-angiotensin system.