Arginine vasopressin receptor 1B (AVPR1B, previously known as vasopressin 3 receptor or antidiuretic hormone receptor 1b) 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. AVPR1B belongs to the subfamily of G-protein coupled receptors. Its activity is mediated by G proteins which stimulate a phosphatidylinositol

Phosphatidylinositol

Phosphatidylinositol is a negatively charged phospholipid and a minor component in the cytosolic side of eukaryotic cell membranes....

-calcium

Calcium

Calcium is the chemical element with the symbol Ca and atomic number 20. It has an atomic mass of 40.078 amu. Calcium is a soft gray alkaline earth metal, and is the fifth-most-abundant element by mass in the Earth's crust...

 second messenger system.

Tissue distribution

AVPR1B was initially described as a novel vasopressin receptor located in the anterior pituitary

Anterior pituitary

A major organ of the endocrine system, the anterior pituitary, also called the adenohypophysis, is the glandular, anterior lobe of the pituitary gland...

, where it stimulates ACTH release. Subsequent studies have shown that it is also present in the brain.

Behavioral

Inactivation of the Avpr1b gene in mice (knockout) produces mice with greatly reduced aggression and a reduced ability to recognize recently investigated mice. Interestingly, defensive behaviour and predatory behaviours appear normal in these knockout mice, but there is evidence that social motivation or awareness is reduced. The AVPR1B antagonist, SSR149415, has been shown to have anti-aggressive actions in hamsters and anti-depressant- and anxiety (anxiolytic)-like behaviors in rats. A single nucleotide polymorphism

Single nucleotide polymorphism

A single-nucleotide polymorphism is a DNA sequence variation occurring when a single nucleotide — A, T, C or G — in the genome differs between members of a biological species or paired chromosomes in an individual...

 (SNP) has been associated with susceptibility to depression in man.

Metabolic

Various stress-induced elevations of ACTH are blunted in the Avpr1b knockout mouse.

Oncology

AVPR1B is expressed at high levels in ACTH-secreting pituitary adenoma

Pituitary adenoma

Pituitary adenomas are tumors that occur in the pituitary gland, and account for about 15% of intracranial neoplasms. Tumors which exceed 10 mm in size are defined as macroadenomas, and those smaller than 10 mm are referred to as microadenomas...

s as well as in bronchial carcinoids responsible for the ectopic ACTH syndrome.

Ligands

Nelivaptan (SSR149415) and D-[Leu⁴-Lys⁸]-vasopressin are a specific antagonist

Receptor antagonist

A receptor antagonist is a type of receptor ligand or drug that does not provoke a biological response itself upon binding to a receptor, but blocks or dampens agonist-mediated responses...

 and agonist

Agonist

An agonist is a chemical that binds to a receptor of a cell and triggers a response by that cell. Agonists often mimic the action of a naturally occurring substance...

for the vasopressin 1b receptor, respectively.

External links