Pituitary Gland By: Gabriel Smith & Riley Pierce 1-12-14 6th 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 HypothalamoHypophyseal 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.
Resources • http://health.howstuffworks.com/human-body/parts/what-does-pituitary-gland-do.htm • http://neurosurgery.ucla.edu/body.cfm?id=1123&ref=82&action=detail • http://health.howstuffworks.com/human-body/parts/what-does-pituitary-gland-do.htm • http://www.innerbody.com/image/endo01.html