adrenergic receptor

(redirected from Beta receptors)
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adrenergic receptor

Etymology: L, ad + ren, kidney; Gk, ergon, work; L, recipere, to receive
a site in a sympathetic effector cell that reacts to adrenergic stimulation. Two types of adrenergic receptors are recognized: alpha-adrenergic, which act in response to sympathomimetic stimuli, and beta-adrenergic, which block sympathomimetic activity. In general, stimulation of alpha receptors is excitatory of the function of the host organ or tissue, and stimulation of the beta receptors is inhibitory.

Adrenergic Receptor

Any of a family of G protein-coupled cell membrane receptors which receive neuronal impulses from postganglionic adrenergic fibres of the sympathetic nervous system, which are divided into:
(1) Alpha receptors, which evoke an excitatory response of smooth muscle cells to catecholamines. Alpha receptors are divided into alpha1 (Gq) and alpha2 (Gi) coupled receptors.
Selective agonist, alpha receptor Phenylephrine
Alpha receptor effects Vasoconstriction, reduced GI tract motility.
(2) Beta receptors, which dampen the response to catecholamines. Beta receptors are divided into beta1, beta2, beta3, which are linked to Gs, and adenylate cyclase, increasing cAMP, which in turn drives cAMP-dependent protein kinase that mediates intracellular events.
Selective agonist, beta receptor Isoprenaline
Beta receptor effects Increased cardiac output, increased renin secretion from juxtaglomerular cells, increased gastric ghrelin secretion, smooth muscle relaxation resulting in bronchodilation, reduced GI motility, relaxation of detrusor muscle of the bladder, lipolysis, glycogenolysis and gluconeogenesis, increased renin secretion, insulin secretion, vasodilation, anabolism and thermogenesis of skeletal muscle.

adrenergic receptor

Neurophysiology Any of a family of cell membrane receptors that receive neuronal impulses from postganglionic adrenergic fibers from the sympathetic nervous sytem, which are divided into α receptors, which results in an excitatory response of smooth muscle cells to catecholamines, and β receptors, which result in an inhibitory response to catecholamines; the GI tract is an exception, in that either α or β receptor stimulation results in relaxation

Adrenergic receptor

There are three families of adrenergic receptors, alpha1, alpha2 and beta, and each family contains three distinct subtypes. Each of the nine subtypes are coded by separate genes, and display specific drug specificities and regulatory properties.
References in periodicals archive ?
Discovered only a decade ago, the beta receptor has been found to protect against cancer, keep the immune system in check, help serious trauma patients survive their injuries, and keep people from being too anxious.
Though mice without the beta receptor can live, they are plagued by a list of health problems--a list that continues to grow as researchers observe the mice aging.
Bonnie Deroo, of the University of Western Ontario, in London (Canada), studies one impact of the missing beta receptor in female mice--fertility problems.
This link doesn't surprise Gustafsson--the beta receptor responds to phytoestrogens much more potently than the alpha receptor does.
Gustafsson's lab has shown that compounds that bind to only the beta receptor stop cells from multiplying.
Compounds that bind to the beta receptor but not the alpha version, called ER[beta]-specific agonists, also may be beneficial for a host of other health problems.
Around the same time the link to chronic inflammation was found, researchers studying mice lacking the beta receptor noticed that the mice's immune systems weren't good at fighting off pathogens.