Arginine vasopressin receptor 2
Encyclopedia
Arginine vasopressin
receptor 2 (officially abbreviated AVPR2) is a protein
that acts as receptor
for arginine vasopressin. AVPR2 belongs to the subfamily of G-protein-coupled receptors. Its activity is mediated by the Gs
type of G proteins, which stimulate adenylate cyclase
.
AVPR2 is expressed in the kidney tubule, predominantly in the membrane of cells of the distal convoluted tubule
and collecting ducts, in fetal lung
tissue and lung cancer
, the last two being associated with alternative splicing
. AVPR2 is also expressed outside the kidney, and, when stimulated, a variety of clotting factors are released into the bloodstream.
In the kidney, AVPR2's primary property is to respond to arginine vasopressin by stimulating mechanisms that concentrate the urine
and maintain water
homeostasis
in the organism. When the function of AVPR2 is lost, the disease Nephrogenic Diabetes Insipidus
(NDI) results.
s that are selective for the V2 receptor include:
Their main uses are in hyponatremia
, such as that caused by syndrome of inappropriate antidiuretic hormone
(SIADH) and cirrhosis
.
with C1QTNF1
.
Vasopressin
Arginine vasopressin , also known as vasopressin, argipressin or antidiuretic hormone , is a neurohypophysial hormone found in most mammals, including humans. Vasopressin is a peptide hormone that controls the reabsorption of molecules in the tubules of the kidneys by affecting the tissue's...
receptor 2 (officially abbreviated AVPR2) is a protein
Protein
Proteins are biochemical compounds consisting of one or more polypeptides typically folded into a globular or fibrous form, facilitating a biological function. A polypeptide is a single linear polymer chain of amino acids bonded together by peptide bonds between the carboxyl and amino groups of...
that acts as receptor
Vasopressin receptor
A vasopressin receptor is a cell surface receptor which binds vasopressin. The three types of vasopressin receptor are members of the A6 subfamily of G-protein coupled receptors.-Subtypes:Humans express three subtypes: 1A, 1B and 2-Function:...
for arginine vasopressin. AVPR2 belongs to the subfamily of G-protein-coupled receptors. Its activity is mediated by the Gs
Gs alpha subunit
The Gs alpha subunit is a heterotrimeric G protein subunit that activates the cAMP-dependent pathway by activating adenylate cyclase.-Receptors:The G protein-coupled receptors that couple to this kind of G-protein include:...
type of G proteins, which stimulate adenylate cyclase
Adenylate cyclase
Adenylate cyclase is part of the G protein signalling cascade, which transmits chemical signals from outside the cell across the membrane to the inside of the cell ....
.
AVPR2 is expressed in the kidney tubule, predominantly in the membrane of cells of the distal convoluted tubule
Distal convoluted tubule
The distal convoluted tubule is a portion of kidney nephron between the loop of Henle and the collecting duct system.- Physiology :It is partly responsible for the regulation of potassium, sodium, calcium, and pH...
and collecting ducts, in fetal lung
Lung
The lung is the essential respiration organ in many air-breathing animals, including most tetrapods, a few fish and a few snails. In mammals and the more complex life forms, the two lungs are located near the backbone on either side of the heart...
tissue and lung cancer
Lung cancer
Lung cancer is a disease characterized by uncontrolled cell growth in tissues of the lung. If left untreated, this growth can spread beyond the lung in a process called metastasis into nearby tissue and, eventually, into other parts of the body. Most cancers that start in lung, known as primary...
, the last two being associated with alternative splicing
Alternative splicing
Alternative splicing is a process by which the exons of the RNA produced by transcription of a gene are reconnected in multiple ways during RNA splicing...
. AVPR2 is also expressed outside the kidney, and, when stimulated, a variety of clotting factors are released into the bloodstream.
In the kidney, AVPR2's primary property is to respond to arginine vasopressin by stimulating mechanisms that concentrate the urine
Urine
Urine is a typically sterile liquid by-product of the body that is secreted by the kidneys through a process called urination and excreted through the urethra. Cellular metabolism generates numerous by-products, many rich in nitrogen, that require elimination from the bloodstream...
and maintain water
Water
Water is a chemical substance with the chemical formula H2O. A water molecule contains one oxygen and two hydrogen atoms connected by covalent bonds. Water is a liquid at ambient conditions, but it often co-exists on Earth with its solid state, ice, and gaseous state . Water also exists in a...
homeostasis
Homeostasis
Homeostasis is the property of a system that regulates its internal environment and tends to maintain a stable, constant condition of properties like temperature or pH...
in the organism. When the function of AVPR2 is lost, the disease Nephrogenic Diabetes Insipidus
Nephrogenic diabetes insipidus
Nephrogenic diabetes insipidus is a form of diabetes insipidus due primarily to pathology of the kidney. This is in contrast to central/neurogenic diabetes insipidus, which is caused by insufficient levels of antidiuretic hormone /Argenine Vasopressin...
(NDI) results.
Antagonists
Vasopressin receptor antagonistVasopressin receptor antagonist
A vasopressin receptor antagonist is an agent which interferes with action at the vasopressin receptors. They can be used in the treatment of hyponatremia, especially in patients with congestive heart failure or liver cirrhosis.-Tetracyclines:...
s that are selective for the V2 receptor include:
- TolvaptanTolvaptanTolvaptan , also known as OPC-41061, is a selective, competitive vasopressin receptor 2 antagonist used to treat hyponatremia associated with congestive heart failure, cirrhosis, and the syndrome of inappropriate antidiuretic hormone . Tolvaptan was approved by the U.S...
(FDA-approved) - LixivaptanLixivaptanLixivaptan is a phase III pharmaceutical being developed by Cardiokine, Inc., a specialty pharmaceutical company based in Philadelphia, PA, focused on the development of pharmaceuticals for the treatment and prevention of cardiovascular diseases...
- MozavaptanMozavaptanMozavaptan is a vasopressin receptor antagonist marketed by Otsuka. In Japan, it was approved in October 2006 for hyponatremia caused by syndrome of inappropriate antidiuretic hormone due to ADH producing tumors....
- SatavaptanSatavaptanSatavaptan is a vasopressin-2 receptor antagonist undergoing research for the treatment of hyponatremia. It is also being studied for the treatment of ascites....
Their main uses are in hyponatremia
Hyponatremia
Hyponatremia is an electrolyte disturbance in which the sodium concentration in the serum is lower than normal. In the vast majority of cases, hyponatremia occurs as a result of excess body water diluting the serum sodium and is not due to sodium deficiency. Sodium is the dominant extracellular...
, such as that caused by syndrome of inappropriate antidiuretic hormone
Syndrome of inappropriate antidiuretic hormone
The syndrome of inappropriate antidiuretic hormone hypersecretion is characterized by excessive release of antidiuretic hormone from the posterior pituitary gland or another source. The result is hyponatremia and sometimes fluid overload...
(SIADH) and cirrhosis
Cirrhosis
Cirrhosis is a consequence of chronic liver disease characterized by replacement of liver tissue by fibrosis, scar tissue and regenerative nodules , leading to loss of liver function...
.
Interactions
Arginine vasopressin receptor 2 has been shown to interactProtein-protein interaction
Protein–protein interactions occur when two or more proteins bind together, often to carry out their biological function. Many of the most important molecular processes in the cell such as DNA replication are carried out by large molecular machines that are built from a large number of protein...
with C1QTNF1
C1QTNF1
Complement C1q tumor necrosis factor-related protein 1 is a protein that in humans is encoded by the C1QTNF1 gene.-Interactions:C1QTNF1 has been shown to interact with Arginine vasopressin receptor 2.-Further reading:...
.