In mammals, they are two triangle-shaped endocrine glands, one each located on top of each kidney (see figure below). They consist of the adrenal cortex that secretes about 30 different steroid hormones (e.g., cortisol, oestrogen) and the adrenal medulla that secretes epinephrine. When the glands produce too many or too few hormones, disease conditions can occur (e.g., Addison’s disease, Cushing’s disease). Also called the suprarenal glands, they are mainly responsible for regulating responses to stress by means of the synthesis of corticosteroids and catecholamines, including cortisol and adrenalin.
