The adrenal gland is a small gland that is part of the Endocrine System whose function is the regulation of stress.

This gland is located above each of the Kidneys.

It is considered an endocrine gland because they release hormones in times of stress.

The gland can be divided into two aspects: 

1.) Adrenal medulla
2.) Adrenal Cortex

Adrenal Medulla

This is the center or core of the adrenal gland.

The, other half, the adrenal cortex surrounds the medulla.

Chromaffin cells are found in the medulla and this is where “catecholamine” hormones are synthesized.

The two primary Catechomins are:

-    Adrenaline (Epinephrine)

-    Noradrenaline (Norepinephrine)


These hormones are essential in the Nervous System.

The “flight-or-fight” response of the central nervous system is dependent on stress which can cause these hormones to become active.

The Sympathetic Nervous system or “flight-or-fight” response is activated from fibers originating in the spinal cord.

Cortisol also helps receptors in the Medulla which triggers a series of reactions and results by increasing epinephrine synthesis and secretion.


The Adrenal Cortex

This is the outer layer of the adrenal gland.

The cells in this region are designed to synthesis hormones referred to as “Corticosteroids“.

The Cortex is regulated or controlled by hormones produced in the brain.

The Pituitary gland and the Hypothalamus trigger the Cortex.

This can also be done by the renin-angiotensin system

The three main hormones produced are:

-   Cortisol
-   Corticosterone
-   Testosterone
-   Aldosterone

The cortex is divided into 3 regions:

1.)   Zona Glomerulosa
2.)   Zona Fasciluata
3.)   Zona Reticularis

VN:F [1.9.22_1171]
Rating: 6.7/10 (17 votes cast)
VN:F [1.9.22_1171]
Rating: +15 (from 17 votes)
Adrenal gland, 6.7 out of 10 based on 17 ratings