Vasopressin antidiuretic

Stmctural defects at the receptor level are determinant for a number of receptor diseases. In nephrogenic diabetes insipidus, where patients void large volumes of dilute urine even in the presence of vasopressin (antidiuretic hormone) (105), the disease is linked to mutations in three discrete regions of the G-protein-linked vasopressin (V2) receptor (106,107). 

Vasopressin (antidiuretic hormone [ADH]) secretion increases in response to decreased blood volume and/or reductions in effective blood volume via a decrease in inhibitory tone from both low-pressure and high-pressure baroreceptors to the hypothalamus. The neuronal pathways that mediate hemodynamic regulation of... 

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. 

Vasopressin (antidiuretic hormone) is a peptide synthesized in the hypothalamus and secreted from the neurohypophysis of the pituitary gland. This substance plays an important role in the long-term regulation of blood pressure through its action on the kidney to increase reabsorption of water. The major stimulus for release of vasopressin is an increase in plasma osmolarity. The resulting reabsorption of water dilutes the plasma toward its normal value of 290 mOsM. This activity is discussed in more detail in Chapter 10 (the endocrine system) and Chapter 19 (the renal system). 

In order to make adjustments in the water load, the reabsorption of the remaining 20% of the filtered water from the distal tubule and the collecting duct is physiologically controlled by antidiuretic hormone (ADH), also referred to as vasopressin. Antidiuretic hormone, synthesized in the hypothalamus and released from the neurohypophysis of the pituitary gland, promotes the... 

Neurohypophysis. Release of vasopressin (antidiuretic hormone) results in lowered urinary output (p. 164). Levels of vasopressin necessary for vasoconstriction will rarely be produced by nicotine. 

The smallest functional unit of the kidney is the nephron. In the glomerular capillary loops, ultrafiltration of plasma fluid into Bowman s capsule (BC) yields primary urine. In the proximal tubules (pT), approx. 70% of the ultrafiltrate is retrieved by isoosmotic reabsorption of NaCl and water. In the thick portion of the ascending limb of Henle s loop (HL), NaCl is absorbed unaccompanied by water. This is the prerequisite for the hairpin countercurrent mechanism that allows build-up of a very high NaQ concentration in the renal medulla In the distal tubules (dT), NaCl and water are again jointly reabsorbed. At the end of the nephron, this process involves an aldosterone-controlled exchange of Na+ against 1C or H. In the collecting tubule (C), vasopressin (antidiuretic hormone, ADH) increases the epithelial permeability for water, which is drawn into the hyperosmolar milieu of the renal medulla and thus retained in the body. As a result, a concentrated urine enters the renal pelvis. 

Water. Water resorption in the proximal tubule is a passive process in which water follows the osmotically active particles, particularly the Na" ions. Fine regulation of water excretion (diuresis) takes place in the collecting ducts, where the peptide hormone vasopressin (antidiuretic hormone, ADH) operates. This promotes recovery of water by stimulating the transfer of aquaporins (see p. 220) into the plasma membrane of the tubule cells via V2 receptors. A lack of ADH leads to the disease picture of diabetes insipidus, in which up to 30 L of final urine is produced per day. 

Vasopressin (antidiuretic hormone) 9 Inhibitory to neurons may facilitate learning and memory... 

Historically vasopressin and oxytocin, two nonapep-tides, were the first peptide neurohormones to be considered they are stored in the neurohypophysis and released into the bloodstream upon an appropriate stimulus. In the periphery, oxytocin stimulates the contraction of epididymal and uterine smooth muscle (see Chapter 62) and vasopressin (antidiuretic hormone) facilitates the reabsorption of water from the kidney tubules. In addition to these well-accepted roles as neurohormones, there is convincing evidence that these compounds function as neurotransmitters they both possess potent inhibitory actions on neurohypophyseal neurons. The significance of their neurotransmitter function is not yet clear. 

Arginine vasopressin antidiuretic hormone ADH pitressin tonephin vasophysin)... 

Other examples include the pituitary hormones vasopressin (antidiuretic hormone, ADH), oxytocin, and adrenocorticotrophic (stimulating) hormone (ACTH) ... 

The axonal processes of hypothalamic neurons project to the neurohypophysis, where they store the nonapeptides vasopressin (= antidiuretic hormone, ADH) and oxytocin and release them on demand into the blood. Therapeutically (ADH, p.168, oxytocin, p.130), these peptide hormones are given parenterally or via the nasal mucosa. 

Vasopressin (antidiuretic ADH Kidney, constriction of Re-absorption of water. 

B. Aldosterone causes resorption of sodium ions and, consequently, the resorption of water. Vasopressin (antidiuretic hormone) causes water resorption. 

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... 

Vasopressin (antidiuretic Hyperosmolality Hypervolemia Acts on renal collecting ducts to... 

Vasopressin Antidiuretic hormone a nine-amino acid peptide that is synthesized by the hypothalamus and controls resorption of water by distal tubules of the kidney. It stimulates the insertion of water channels (aqua-porins) into the apical membranes of kidney tubules. 

Chlorpromazine may have weak diuretic effects because of a depressant action on the secretion of vasopressin (antidiuretic hormone, ADH), inhibition of reabsorption of water and electrolytes by a direct action on the renal tubule, or both. The syndrome of idiopathic polydipsia and hyponatremia sometimes associated with psychotic illness has respotuled to clozapine, presumably via... 

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. 

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