The pituitary gland and its function

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					The pituitary gland and its functions for the person


Pituitary contains 3 parts - the front, middle and rear.
anterior pituitary, or adenohypophysis, performs in the endocrine orchestra as the role of the
conductor. As mentioned above, a role he performs with tropic hormones that regulate the activity of the
adrenal cortex (adrenocorticotropic hormone), gonads (gonadtropnye hormones) and thyroid (thyroid
stimulating hormone). In addition, adrenogipofiz allocates growth hormone, or HGH.
Under the influence of growth hormone in children is an acceleration of growth. With the lack of this
hormone in the development of early man is a midget. Excessive production of this hormone in children
develops gigantism (growth of man reaches sometimes even 240-250 cm). I excessive production of
growth hormone in adults can lead to a disease called acromegaly. It manifests itself in a disproportionate
increase in the size of the distal parts of the body (fingers, hands, feet, nose, lower jaw).
Growth hormone increases the synthesis of proteins, cells, promotes the optimal use of nutrients,
increases the release of fatty acids from adipose tissue and in certain circumstances, the use of
carbohydrates inhibits tissue.
The factors that stimulate the production and release of tropic hormones of the anterior pituitary are
specific neurohormones (releasing factor) released by neurosecretory cells of the hypothalamus. Products
tropic hormones are also regulated by the content of the regulated hormone produced by them. This is a
typical example of a regulation by a negative feedback loop: increase of regulated hormone inhibits,
reducing it increases the production of the regulator - tropic hormones.
Physical activity causes increased production of growth hormone and adrenocorticotropic. Probably also
enhanced secretion of thyroid-stimulating hormone, but inhibited the secretion of HCG. In a state of
fatigue, depressed secretion of adrenocorticotropic hormone. When seeing a new work increased
secretion of this hormone.
Intermediate lobe of the pituitary in humans is poorly developed. Its product - melanophore hormone
promotes the formation of the brown pigment that causes the darkening of the skin coloration.
Posterior lobe of the pituitary, or neurohypophysis, identifies two neurohormones, place of education
which are neurosecretory cells. One of them - antidiuretic hormone - regulates body water content and
volume of fluid in the blood vessels. With the depletion of body water (increased osmotic pressure of
blood) increases the secretion of the hormone. The main action of antidiuretic hormone associated with
the tubules of the kidneys, which increases the reabsorption of water. As a result, urine output
decreases. Physical activity (such as those that cause increased sweating) increase the secretion of
antidiuretic hormone.
Another posterior pituitary hormone - oxytocin - helps to reduce muscle of the pregnant uterus during
labor. During lactation, it promotes the separation of milk.

				
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