Receptor (biochemistry)

In biochemistry and pharmacology, a receptor is a protein-molecule that receives chemical-signals from outside a cell. When such chemical-signals bind to a receptor, they cause some form of cellular/tissue-response, e.g. a change in the electrical-activity of a cell. In this sense, a receptor is a protein-molecule that recognises and responds to endogenous-chemical signals, e.g. an acetylcholine-receptor recognizes and responds to its endogenous-ligand, acetylcholine. However, sometimes in pharmacology, the term is also used to include other proteins that are drug-targets, such as enzymes, transporters and ion-channels.

Receptor-proteins are embedded in all cells' plasmatic-membranes; facing extracellular-(cell surface receptors), cytoplasmic (cytoplasmic-receptors), or in the nucleus (nuclear receptors). A molecule that binds to a receptor is called a ligand, and can be a peptide (short-protein) or another small molecule such as a neurotransmitter, hormone, pharmaceutical-drug, toxin, or parts of the outside of a virus or microbe. The endogenously designated-molecule for a particular receptor is referred to as its endogenous-ligand. E.g. the endogenous-ligand for the nicotinic-acetylcholine receptor is acetylcholine but the receptor can also be activated by nicotine and blocked by curare.

Immune receptor

An immune receptor (or immunologic receptor) is a receptor, usually on a cell membrane, which binds to a substance (for example, a cytokine) and causes a response in the immune system.

Types

The main receptors in the immune system are pattern recognition receptors (PRRs), Toll-like receptors (TLRs), killer activated and killer inhibitor receptors (KARs and KIRs), complement receptors, Fc receptors, B cell receptors and T cell receptors.

See also

References

External links

Beta-1 adrenergic receptor

The beta-1 adrenergic receptor (β₁ adrenoreceptor), also known as ADRB1, is a beta-adrenergic receptor, and also denotes the human gene encoding it. It is a G-protein coupled receptor associated with the Gs heterotrimeric G-protein and is expressed predominantly in cardiac tissue.

Receptor

Actions

Actions of the β₁ receptor include:

Burst (village)

Burst is a sub-municipality of Erpe-Mere in Belgium. It is located on the Molenbeek in the Denderstreek, southeast of East Flanders and belongs to the Arrondissement of Aalst. It is bordered by the sub-municipalities of Bambrugge and Aaigem, as well as the municipalities of Herzele (sub-municipalities Ressegem and Borsbeke) and Sint-Lievens-Houtem (sub-municipalities Zonnegem and Vlierzele). Burst had 2968 inhabitants on 1 January 2003 and an area of 3.83 km. The population density was 776 / km ².

History

The name Burst was first found in a charter of the Sint-Pietersabdij (Abbey) in Ghent. In this document of 1042 it is said that the village Burste is in the neighbourhood of a river with the same name, the "Bursitia juxta fluviolum Burste". It was not until a century later however, in 1151, that Burst was described under its present name, and the village was in the following decades, also named in several documents as Borst, Bost and Bust. The village had 125 farms in 1846, including some large ones. At that time there was a wheat windmill, three breweries and three distilleries in the village. At the beginning of the 19th century, the village had 304 inhabitants, and by the beginning of the 20th century it had 963 inhabitants.

Burst Radio

Bristol University Radio Station (Burst) is the radio station run by students of the University of Bristol, England. Its studios are located within the University of Bristol Union building, and it broadcasts online. The station was initially known as BURST FM, but this name has now been dropped as the station no longer regularly broadcasts on FM. The station is generally not on air during university vacations.

History

In 1995, students from Bristol University and the University of the West of England (UWE) co-operated to run Fresh FM. After Fresh FM ceased to exist, BURST FM was conceived by Bristol University students in 1997. When sufficient funds had been raised, a one-month licence to broadcast on 106.6 FM was awarded for March 1998. Housed in St Paul's Church in Clifton.

However, the unavailability of further FM licences due to the launch of a new full-time station (The Eagle, now renamed Star) prevented further broadcasts. In early 2000 speakers were installed within the Union building, and broadcasts mounted for during Fresh (Bristol University's Freshers' Week) 2000. At the same time, a grant from the Alumni foundation and fundraising through advertising and sponsorship allowed BURST to build new studios inside the Union and stream programming onto the internet around campus.