Posterior pituitary gland hormones

There may be a decreased resistance and inability to The posterior pituitary gland produces two hormones localize infection. The nurse observes the skin daily for vasopressin (antidiuretic hormone) and oxytocin (see localized signs of infection, especially at injection sites Chap. 53). Posterior pituitary hormones are summarized or IV access sites. Visitors are monitored to protect the in the Summary Drag Table Anterior and Posterior patient against those witii infectious illness. Pituitary Hormones. 

Posterior pituitary Two hormones, vasopressin and oxytocin, are synthesised in the hypothalamus and then transported through nerve axons to the posterior pituitary, where they are stored until released. Vasopressin acts on the kidney to conserve water. Its secretion is stimulated by thirst and a decrease in blood pressure. Secretion of oxytocin initiates uterine contraction for parturition. It also stimulates milk ejection from the mammary glands. 

Water excretion is further controlled by the antidiuretic hormone from the posterior pituitary gland which acts to increase water resorption in the kidney through making the collecting tubule permeable to water for additional resorption beyond what took place in the tubule. The posterior pituitary gland secretes the hormone as a rapid and sensitive response... 

The posterior pituitary gland is the source of circulating oxytocin and vasopressin (iantidiuretic hormone, ADH). These hormones are actually produced in specific nerve cells in the hypothalamus and travel down the axons into the neuro-hypophysis. The structures of oxytocin and vasopressin are shown in Chapter 4. It may be seen that both are nanopeptides with disulfide bonds and that they differ by two amino acids only. Both hormones originate from larger proteins vasopressin from prepressophysin and oxytocin from pro-oxyphysin. These are converted to pressophysin and oxyphysin, respectively (collectively,... 

Any significant rise or drop in plasma osmolality is detected by the hypothalamus, which communicates directly with the posterior pituitary gland. A rise in osmolality causes the gland to secrete antidiuretic hormone, resulting in water reabsorption by the kidney and an increase in urine concentration. The two factors work together to return the plasma osmolality to its normal levels. 

Q9 The hormone that contracts the uterus during labour is the peptide hormone oxytocin, which is released from the posterior pituitary gland. 

Oxytocin is a peptide hormone of the posterior pituitary gland. It stimulates the contractions of the pregnant uterus, which becomes much more sensitive to it at term. Patients with posterior pituitary disease (diabetes insipidus) can, however, go into labour normally. 

Water and electrolyte metabohsm is regulated by aldosterone from the adrenal gland, renin from the kidney, and vasopressin (antidiuretic hormone [ADH]) from the posterior pituitary gland (see Chapters 45 and 46). 

The posterior pituitary gland secretes two major hormones, oxytocin and vasopressin (antidiuretic hormone) (Table 75-1). Oxytocin... 

Oxytocin—A pol5q)eptide hormone secreted by the posterior pituitary gland that stimulates uterine contraction. 

Neurophysin A protein that is secreted with oxytocin and vasopressin from the posterior pituitary gland. Neurophysin binds to these two hormones and stabihzes them. 

The posterior pituitary gland secretes two hormones, antidiuretic hormone (ADH) and oxytocin. They are both synthesized in the hypothalamus and reach the posterior pituitary via a neural connection. See Figure 6.2. 

The second hormone that originates from the posterior pituitary gland is antidiuretic hormone, or vasopressin. It has the following amino-acid sequence ... 

The kidneys play important roles in regulating acid-base balance, water and electrolyte balance, blood volume, and blood pressure by interacting with blood hormones. For example, any major change of plasma osmolality is detected by the hypothalamus, which relays messages to the posterior pituitary gland, which then alters the secretion of antidiuretic hormones. Some metabolites (e.g., amino acids and glucose, which are filtered by the glomeruli) are reabsorbed by the tubules and conserved for recirculation. 

Alcohol inhibits the release of vasopressin (antidiuretic hormone see Chapter 29) from the posterior pituitary gland, resulting in enhanced diuresis. The volume loading that accompanies imbibing complements the diuresis that occurs as a result of reduced vasopressin secretion. Alcoholics have less urine output than do control subjects in response to a challenge dose with ethanol, suggesting that tolerance develops to the diuretic effects of ethanol. Alcoholics withdrawing from alcohol exhibit increased vasopressin release and a consequent retention of water, as well as dilutional hyponatremia. 

The posterior pituitary gland produces two honnones vasopressin (antidiuretic honnone) and oxjrtncin (see (3iap. 53). Ibsterior ixtuitary honnones are summarized in die Summary Dmg Table Anterior and Ibsterior Rtuitary Hormones. 

The posterior pituitary gland secretes antidiuretic hormone (ADH) and oxytocin. ADH is a vasopressin. Ox5docin is released to start labor contractions. ADH promotes water reabsorption from the renal tubules to maintain water balance in the body s fluids. A deficiency of ADH, called diabetes insipidus (Dl), causes the kidneys to excrete large amounts of water. This leads to severe fluid volume deficit and electrol5de imbalances. 

Oxytocin is a hormone produced naturally in females posterior pituitary glands, which are located at the back of the brain. It is responsible for causing lactation and uterine contractions in pregnant women. Oxytocin is also used to induce labor when a pregnancy does not begin on time naturally. 

In an investigation by Heller and Zaimir (1949), the antidiuretic hormone concentration of the posterior pituitary gland was determined in samples obtained from 15 newborn children, 2 adolescent children, and 12 adults. The posterior lobe of the newborn infants was found to possess only about one-fifth of the hormone activity observed in adults, the mean values for the two groups being, respectively, 166 and 762 milliunits per milligram of dry tissue. Moderately higher hormone values (approximately 1000 milliunits per milligram of dry tissue) were recorded for the tissue samples from 14- and 15-year-old children. 

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