FYI: Basic Adrenal Gland Info

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http://www.umm.edu/endocrin/adrengl.htm

The Adrenal Glands

Anatomy of the adrenal glands:

Adrenal glands, which are also called

suprarenal glands, are small, triangular

glands located on top of both kidneys. An

adrenal gland is made of two parts: the outer

region is called the adrenal cortex and the

inner region is called the adrenal medulla.

Function of the adrenal glands:

The adrenal glands work interactively with the

hypothalamus and pituitary gland in the

following process:

the hypothalamus produces

corticotropin-releasing hormones,

which stimulate the pituitary gland.

the pituitary gland, in turn, produces

corticotropin hormones, which

stimulate the adrenal glands to produce

corticosteroid hormones.

Both parts of the adrenal glands -- the adrenal

cortex and the adrenal

medulla -- perform very separate functions.

What is the adrenal cortex?

The adrenal cortex, the outer portion of the

adrenal gland, 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. The

hormones produced by the adrenal cortex include:

corticosteroid hormones

hydrocortisone hormone - this hormone,

also known as

cortisol, controls the body's use of

fats, proteins, and

carbohydrates.

corticosterone - this hormone, together

with

hydrocortisone hormones, suppresses

inflammatory

reactions in the body and also affects

the immune system.

aldosterone hormone - this hormone inhibits

the level of sodium

excreted into the urine, maintaining blood

volume and blood pressure.

androgenic steroids (androgen hormones) -

these hormones

have minimal effect on the development of

male characteristics.

What is the adrenal medulla?

The adrenal medulla, the inner part of the adrenal

gland, is not essential to

life, but helps a person in coping with physical

and emotional stress. The

adrenal medulla secretes the following hormones:

epinephrine (also called adrenaline) -

this hormone

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 (also called

noradrenaline) - this

hormone has little effect on smooth

muscle, metabolic

processes, and cardiac output, but has

strong

vasoconstrictive effects, thus

increasing blood pressure.

http://www.encyclopedia.com/articles/00132.html

adrenal gland

adrenal gland

Pronounced As: drnl or suprarenal gland sooprrnl ,

endocrine gland (see endocrine system) about 2 in.

(5.1 cm) long situated atop each kidney. The outer

yellowish layer (cortex) of the adrenal gland secretes

about 30 steroid hormones, the most important of

which are aldosterone and cortisol. Cortisol regulates

carbohydrate, protein, and fat metabolism, and its

secretion is controlled by the output of

adrenocorticotropic hormone (ACTH) from the pituitary

gland. Aldosterone regulates water and salt balance in

the body; its secretion is only slightly influenced by the

pituitary. Steroid hormones also counteract

inflammation and allergies and influence the

secondary sex characteristics to a limited degree. The

adrenal cortex controls metabolic processes that are

essential to life and if it ceases to function death

ensues within a few days. Artificial synthesis of the

steroid hormones has made it possible to treat many

conditions related to underactivity of the adrenal cortex,

e.g., 's disease. The inner reddish portion

(medulla) of the adrenal gland, which is not functionally

related to the adrenal cortex, secretes epinephrine

(adrenaline) and norepinephrine. The release of these

hormones is stimulated when an animal is excited or

frightened, causing increased heart rate, increased

blood flow to the muscles, elevated blood sugar,

dilation of the pupils of the eyes, and other changes

that increase the body's ability to meet sudden

emergencies.