The
endocrine system is an integrated system of small organs that involve the release of extracellular signaling molecules known as
hormones. The
endocrine system is instrumental in regulating metabolism, growth, development and puberty, tissue function, and also plays a part in determining mood. The field of medicine that deals with disorders of
endocrine glands is
endocrinology, a branch of the wider field of internal medicine.
Endocrine glands regulate your body chemistry by releasing hormones directly in to the blood system, which stimulate or inhibit activity in the target cells. They are like remote-control devices for your body's many cells and systems. It would be far too complicated to communicate with each cell in the body directly, so instead the brain controls similar types of cells using hormones released in to the blood stream. To give you an example of how this works, imagine your sudden rise in heart rate when danger threatens or an emergency situation arises - this is caused by another 'remote control' hormone:
adrenaline. This hormone, released by the adrenal gland on top of your kidney, has a very immediate and noticeable effect on your body. The hormones released from the pituitary gland are way less dramatic and not nearly as instantaneous, but work in a similar fashion and are critical to your overall health and well-being.
The pituitary gland is sometimes called the "master" gland of the
endocrine system, because it controls the functions of all the other endocrine glands. This "
Master Gland" role makes the pituitary gland quite important, despite its small size.
The medical term is
hypophysis (from the Greek, "lying under") which refers to the gland's position on the underside of the brain. The term "
pituitary" is in reference to
secretion, but has come to be synonymous with, and easier to say, than "
hypophysis".
The
hypothalamus is the bottom part of the brain that connects and communicates with the pituitary gland via nerve fibers. This area of the brain functions as the main control center for the
autonomic nervous system by regulating sleep cycles, body temperature, appetite, etc., and that acts as an
endocrine gland by producing hormones, including the releasing factors that control the hormonal secretions of the pituitary gland.
Regulating growth hormones are what people commonly associate the pituitary gland with. Too large an amount of these hormones causes giantism, a condition where facial features, hands, etc. become abnormally large. Too little causes dwarfism, where the overall stature of a person is very small. While the pituitary gland is responsible for regulating growth hormones, it also sends signals to the thyroid gland, adrenal glands, ovaries and testes, directing them to produce thyroid hormone, cortisol, estrogen, testosterone, and many more. These hormones have dramatic effects on metabolism, blood pressure, sexuality, reproduction, and other vital body functions, including prolactin for milk production.
To read the entire article, please visit:
http://www.pituitary.org/library/about.aspx
