Beta-3 adrenergic receptor
Encyclopedia
The beta-3 adrenergic receptor (β3 adrenoreceptor), also known as ADRB3, is an beta-adrenergic receptor, and also denotes the human gene
encoding it.
It is located mainly in adipose tissue
and is involved in the regulation of lipolysis and thermogenesis
. Some β3 agonists have demonstrated antistress effects in animal studies, suggesting it also has a role in the CNS. Beta3-Receptors are found in the gallbladder, urinary bladder, and in brown adipose tissue. Their role in gallbladder physiology is unknown, but they are thought to play a role in lipolysis and thermogenesis in brown fat. In the urinary bladder it is thought to cause relaxation of the bladder and prevention of urination.
- and norepinephrine
-induced activation of adenylate cyclase through the action of the G proteins of the type Gs
.
A selective β3 agonist
has potential weight loss effects through modulation of lipolysis.
with Src
.
Gene
A gene is a molecular unit of heredity of a living organism. It is a name given to some stretches of DNA and RNA that code for a type of protein or for an RNA chain that has a function in the organism. Living beings depend on genes, as they specify all proteins and functional RNA chains...
encoding it.
Function
Actions of the β3 receptor include:- Enhancement of lipolysisLipolysisLipolysis is the breakdown of lipids and involves the hydrolysis of triglycerides into free fatty acids followed by further degradation into acetyl units by beta oxidation. The process produces Ketones, which are found in large quantities in ketosis, a metabolic state that occurs when the liver...
in adipose tissueAdipose tissueIn histology, adipose tissue or body fat or fat depot or just fat is loose connective tissue composed of adipocytes. It is technically composed of roughly only 80% fat; fat in its solitary state exists in the liver and muscles. Adipose tissue is derived from lipoblasts...
. - ThermogenesisThermogenesisThermogenesis is the process of heat production in organisms. It occurs mostly in warm-blooded animals, but a few species of thermogenic plants exist.-Types:...
in skeletal muscleSkeletal muscleSkeletal muscle is a form of striated muscle tissue existing under control of the somatic nervous system- i.e. it is voluntarily controlled. It is one of three major muscle types, the others being cardiac and smooth muscle...
It is located mainly in adipose tissue
Adipose tissue
In histology, adipose tissue or body fat or fat depot or just fat is loose connective tissue composed of adipocytes. It is technically composed of roughly only 80% fat; fat in its solitary state exists in the liver and muscles. Adipose tissue is derived from lipoblasts...
and is involved in the regulation of lipolysis and thermogenesis
Thermogenesis
Thermogenesis is the process of heat production in organisms. It occurs mostly in warm-blooded animals, but a few species of thermogenic plants exist.-Types:...
. Some β3 agonists have demonstrated antistress effects in animal studies, suggesting it also has a role in the CNS. Beta3-Receptors are found in the gallbladder, urinary bladder, and in brown adipose tissue. Their role in gallbladder physiology is unknown, but they are thought to play a role in lipolysis and thermogenesis in brown fat. In the urinary bladder it is thought to cause relaxation of the bladder and prevention of urination.
Mechanism of action
Beta adrenergic receptors are involved in the epinephrineEpinephrine
Epinephrine is a hormone and a neurotransmitter. It increases heart rate, constricts blood vessels, dilates air passages and participates in the fight-or-flight response of the sympathetic nervous system. In chemical terms, adrenaline is one of a group of monoamines called the catecholamines...
- and norepinephrine
Norepinephrine
Norepinephrine is the US name for noradrenaline , a catecholamine with multiple roles including as a hormone and a neurotransmitter...
-induced activation of adenylate cyclase through the action of the G proteins of the type 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:...
.
Agonists
- AmibegronAmibegronAmibegron is a drug developed by Sanofi-Aventis which acts as a selective agonist for the β3 adrenergic receptor. It is the first orally active β3 agonist developed that is capable of entering the Central Nervous System, and has antidepressant and anxiolytic effects.On July 31, 2008,...
(SR-58611A)
- SolabegronSolabegronSolabegron is a drug which acts as a selective agonist for the β3 adrenergic receptor. It is being developed for the treatment of overactive bladder and irritable bowel syndrome.,, It has been shown to produce visceral analgesia by releasing somatostatin from adipocytes. ,-Synthesis:K.H....
(GW-427,353)
- NebivololNebivololNebivolol is a β1 receptor blocker with nitric oxide-potentiating vasodilatory effect used in treatment of hypertension and, in Europe, also for left ventricular failure...
- L-796,568
- CL-316,243
- LY-368,842
- Ro40-2148
A selective β3 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...
has potential weight loss effects through modulation of lipolysis.
Antagonists
- SR 59230ASR 59230ASR 59230A is a selective antagonist of the beta-3 adrenergic receptor, but subsequently shown to also act at α1 adrenoceptors at high doses. It has been shown to block the hyperthermia produced by MDMA in animal studies....
was thought to be a selective β3 antagonistReceptor antagonistA 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...
but later found to also be an antagonist of the α1 receptor.
See also
- Other adrenergic receptorAdrenergic receptorThe adrenergic receptors are a class of metabotropic G protein-coupled receptors that are targets of the catecholamines, especially noradrenaline and adrenaline ....
s- Alpha-1 adrenergic receptorAlpha-1 adrenergic receptorThe alpha-1 adrenergic receptor is a G protein-coupled receptor associated with the Gq heterotrimeric G-protein. It consists of three highly homologous subtypes, including α1A-, α1B-, and α1D-adrenergic...
- Alpha-2 adrenergic receptorAlpha-2 adrenergic receptorThe alpha-2 adrenergic receptor is a G protein-coupled receptor associated with the Gi heterotrimeric G-protein. It consists of three highly homologous subtypes, including α2A-, α2B-, and α2C-adrenergic. Some species other than humans express a fourth α2D-adrenergic receptor as well...
- Beta-1 adrenergic receptorBeta-1 adrenergic receptorThe beta-1 adrenergic receptor , also known as ADRB1, is a beta-adrenergic receptor, and also denotes the human gene encoding it...
- Beta-2 adrenergic receptorBeta-2 adrenergic receptorThe beta-2 adrenergic receptor , also known as ADRB2, is a beta-adrenergic receptor, and also denotes the human gene encoding it.-Gene:The gene is intronless...
- Beta BlockerBeta blockerBeta blockers or beta-adrenergic blocking agents, beta-adrenergic antagonists, beta-adrenoreceptor antagonists or beta antagonists, are a class of drugs used for various indications. They are particularly for the management of cardiac arrhythmias, cardioprotection after myocardial infarction ,...
- Alpha-1 adrenergic receptor
Interactions
Beta-3 adrenergic receptor 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 Src
Src (gene)
Proto-oncogene tyrosine-protein kinase Src is an enzyme that in humans is encoded by the SRC gene.Src is a proto-oncogene encoding a tyrosine kinase originally discovered by J. Michael Bishop and Harold E. Varmus, for which they won the 1989 Nobel Prize in Physiology or Medicine. It belongs to a...
.