Adrenal gland facts for kids

The adrenal gland is a gland in most mammals. It is near the kidneys. Its name tells its position (ad – "near", and renes – "kidneys"). The gland is made up of two types of tissues: the centrally located tissue is called the adrenal medulla and outside this lies the adrenal cortex.

The adrenal glands are known as "suprarenal glands" in humans. In many animals the glands are next to the kidneys, but they are cap-like structures on top of the kidneys in humans.

The adrenal cortex produces three main types of steroid hormones: mineralocorticoids, glucocorticoids, and androgens. Mineralocorticoids (such as aldosterone) help in the regulation of blood pressure and electrolyte balance.

The adrenal gland makes hormones which control stress. It is involved in the production of steroid hormones. Among these hormones are cortisol and adrenaline.

Cortex

Negative feedback in the HPA axis

Steroidogenesis in the adrenal glands – different steps occur in different layers of the gland

The hormones secreted from the cortex region are called adrenocorticosteroids or corticoids. These are the hormones it makes:

• Corticosteroids: all corticosteroids are made from cholesterol.
  • Cortisol / cortisone. These two are in a reversible reaction: they can be changed to each other by an enzyme. Cortisol is the active version, cortisone is the inactive version.
  • Aldosterone: a hormone which regulates blood pressure.
  • Androgens: intermediate male sex hormones.

Medulla

The adrenal medulla, in the center of the gland, makes:

• Adrenaline (U.S = Epinephrine) and noradrenaline (U.S. = norepinephrine): they make the fight or flight response in animals.

Images for kids

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  Section of human adrenal gland under the microscope, showing its different layers. From the surface to the center: zona glomerulosa, zona fasciculata, zona reticularis, medulla. In the medulla, the central adrenomedullary vein is visible.

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  Characteristic skin hyperpigmentation in Addison's disease

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  Incidences and prognoses of adrenal tumors.

See also

In Spanish: Glándula suprarrenal para niños