Equipping People To Make Sense Of What They Are Told
Adrenal Gland - a small, triangular glands located on top of both kidneys.
The adrenal gland is composed of two regions:
The outer region - the adrenal cortex.
The inner region - the adrenal medulla.
The two regions perform very separate functions.
Adrenal Cortex (outer region) - secretes hormones that have an effect on the body's
metabolism, on chemicals in the blood, and on certain body characteristics. The adrenal
cortex secretes corticosteroids and other hormones directly into the bloodstream.
Hormones secreted by the adrenal cortex (outer region) include:
Corticosteroid hormones:
Aldosterone - inhibits the level of sodium excreted into the urine, maintaining blood
volume and blood pressure.
Androgen (androgenic steroids) - these hormones have minimal effect on the development
of men characteristics.
Corticosterone together with hydrocortisone, suppresses inflammatory reactions in
the body and also affects the immune system.
Hydrocortisone - also known as cortisol, controls the body's use of fats, proteins,
and carbohydrates.
Hormones secreted by the adrenal medulla (inner region) include:
Epinephrine (adrenaline) - increases the heart rate and force of heart contractions,
facilitates blood flow to the muscles and brain, causes relaxation of smooth muscles,
helps with conversion of glycogen to glucose in the liver, and other activities.
Norepinephrine (noradrenaline) - has strong vasoconstrictive effects, thus increasing
blood pressure. (has little effect on smooth muscle, metabolic processes, and cardiac
output).
The adrenal medulla (inner region) - is not essential to life, but helps a person
in coping with physical and emotional stress.
Adrenal glands work interactively with the hypothalamus and pituitary Gland.
The hypothalamus produces corticotropin-releasing hormones, which in turn stimulates
the pituitary gland.
the pituitary gland, in turn, produces corticotropin hormones, which stimulates the
adrenal glands to produce corticosteroid hormones.
