PITUITARY GLAND BY: GABRIEL SMITH & RILEY PIERCE TH PERIOD

LOCATION In the middle of the base of the brain, Inferior to the hypothalamus.

POSTERIOR PITUITARY Receives messages from another part of the brain (hypothalamus) if one hormone level gets too low then message will be sent via hormones to return to normal levels. The Pituitary is mostly composed of cells called Pituicytes. Pituicytes play the “acting and supporting” roll which is needed to keep everything maintained. Hormones produced in the hypothalamus nuclei and excreted then stored in the Pituitary Gland. The pituitary gland is termed the “Master Gland” because it directs other organs and endocrine glands

HORMONES Two main hormones are involved with the pituitary gland. Oxytocin and AVP. (Both polypeptides with 9 amino acids) ADH influences water balance, Oxytocin stimulates contraction of smooth muscle, particularly uterus and breast.

TRANSPORTATION Transported along the Hypothalamo Hypophyseal with a protein called neurophysin to store it in the back nerve endings of the gland to be used later on.

ADH Decreases osmotic pressure of the blood by increasing water reabsorption by distal tubules and collecting ducts. (happens in the kidneys) Also activates vasoconstriction, the constriction of blood vessels, which increases blood pressure. Can be caused by severe blood loss causing rising pressure also called vasopressin.

OXYTOCIN. Secretes during labor, and helps with contractions. Also secretes during the ejaculation process.

HYPOPITUITARISM IS PITUITARY FAILURE Causes : Tumor (adenoma), Surgery, Trauma, Radio therapy, Immune Attacks, Isolated deficiency of one hormone since birth. Effects: Growth hormone deficiency, Low cortisol level, weight loss, loose bowels, low blood pressure, blackout and undue tiredness, Low sex hormone levels lethargy, tiredness, severe thirst and copious amounts of urine. Cure: There is currently no cure because there is no known relationship between hypopituitarism and the excess mortality. It is not even know if optimal treatment will improve mortality.

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