A pair of small, triangular endocrine glands located above the kidneys. Each adrenal gland has 2 distinct parts: the outer cortex and the smaller, inner medulla. The cortex secretes aldosterone, which, together with hydrocortisone and corticosterone and small amounts of androgen hormones helps to maintain blood pressure. Hydrocortisone controls the body’s use of fats, proteins, and carbohydrates and is also important in helping the body to cope with stress. Hydrocortisone and corticosterone also suppress inflammatory reactions and some activities of the immune system. Production of adrenal cortical hormones is controlled by ACTH, which is produced in the pituitary gland. The adrenal medulla is part of the sympathetic autonomic nervous system. In response to stress, it secretes the hormones adrenaline (epinephrine) and noradrenaline (norepinephrine), which increase heart-rate and blood flow.
Adrenal glands |
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