# Prostanoid > Mediated Wiki article. Canonical URL: https://mediated.wiki/source/Prostanoid > Markdown URL: https://mediated.wiki/source/Prostanoid.md > Source: https://en.wikipedia.org/wiki/Prostanoid > Source revision: 1329980186 > License: Creative Commons Attribution-ShareAlike 4.0 International (https://creativecommons.org/licenses/by-sa/4.0/) {{Short description|Class of biomolecules regulating inflammatory response}} {{Main|Prostaglandin|Prostacyclin|Thromboxane}} In [molecular biology](/source/molecular_biology), '''prostanoids''' are active [lipid](/source/lipid) mediators that regulate [inflammatory response](/source/Inflammation). Prostanoids are a subclass of [eicosanoid](/source/eicosanoid)s consisting of the [prostaglandin](/source/prostaglandin)s (mediators of [inflammatory](/source/Inflammation) and [anaphylactic](/source/Anaphylaxis) reactions), the [thromboxane](/source/thromboxane)s (mediators of [vasoconstriction](/source/vasoconstriction)), and the [prostacyclin](/source/prostacyclin)s (active in the resolution phase of inflammation).{{fact|date=December 2025}} Prostanoids are seen to target [NSAIDS](/source/NSAIDS) which allow for therapeutic potential. Prostanoids are present within areas of the body such as the [gastrointestinal tract](/source/gastrointestinal_tract), [urinary tract](/source/urinary_tract), [respiratory](/source/respiratory) and [cardiovascular system](/source/cardiovascular_system)s, [reproductive tract](/source/reproductive_tract) and [vascular system](/source/vascular_system). Prostanoids can even be seen with aid to the water and ion [transportation](/source/Active_transport) within cells. == History == Prostanoids were discovered through biological research studies conducted in the 1930s.{{Cite web |last=Christie |first=William (Bill) W. |title=Prostanoids: Prostaglandins, Prostacyclins and Thromboxanes |url=https://www.lipidmaps.org/resources/lipidweb/lipidweb_html/lipids/fa-eic/eicprost/index.htm |access-date=2022-05-12 |website=www.lipidmaps.org |language=en-gb}}{{Cite web |title=prostaglandin {{!}} Definition, Function, Synthesis, & Facts {{!}} Britannica |url=https://www.britannica.com/science/prostaglandin |access-date=2022-05-12 |website=www.britannica.com |language=en}} The first discovery was seen through semen by a Swedish Physiologist [Ulf von Euler](/source/Ulf_von_Euler), who assumed they originated from the prostate. After intensive study throughout the 1960-1970s [Sune K. Bergström](/source/Sune_Bergstr%C3%B6m) and [Bengt Ingemar Samuelsson](/source/Bengt_Ingemar_Samuelsson) and British biochemist Sir John Robert Vane were able to understand the function and chemical formation of Prostanoids: receiving a Nobel Prize for their analysis of prostanoids. == Biosynthesis of prostaglandins == {{Prostanoid biosynthesis|float=right}} [Cyclooxygenase](/source/Cyclooxygenase) (''COX'') catalyzes the conversion of the free essential fatty acids to prostanoids by a two-step process. In the first step, two molecules of O2 are added as two peroxide linkages and a 5-member carbon ring is forged near the middle of the fatty acid chain. This forms the short-lived, unstable intermediate Prostaglandin G (PGG). One of the peroxide linkages sheds a single oxygen, forming PGH. ''(See diagrams and more detail at [Cyclooxygenase](/source/Cyclooxygenase)).'' All other prostanoids originate from PGH (as PGH1, PGH2, or PGH3). The image at right shows how PGH2 (derived from [Arachidonic acid](/source/Arachidonic_acid)) is converted: * By [PGE synthetase](/source/PGE_synthetase) into PGE2 (which in turn is converted into PGF2) * By [PGD synthetase](/source/PGD_synthetase) into PGD2 * By [Prostacyclin synthase](/source/Prostacyclin_synthase) into [prostacyclin](/source/prostacyclin) (PGI2) * By [Thromboxane synthase](/source/Thromboxane_synthase) into [thromboxane](/source/thromboxane)s TXA [Arachidonic acid](/source/Arachidonic_acid) is made up of a 20-Carbon unnatural poly unsaturated Omega-fatty acid.{{fact|date=December 2025}} Arachidonic acid presents within the phospholipid bi-layer as well as in the plasma membrane of a cell. With [Arachidonic acid](/source/Arachidonic_acid) prostaglandins are formed through synthesis and oxygenation of enzymes. Active lipids in the oxylipin family derive from the synthesis of [Cyclooxygenase](/source/Cyclooxygenase) or Prostaglandins. The three classes of prostanoids have distinctive rings in the center of the molecule. They differ in their structures and do not share common structure as Thromboxane. The PGH compounds (parents to all the rest) have a 5-carbon ring, bridged by two oxygens (a [peroxide](/source/peroxide).) The derived prostaglandins contain a single, unsaturated 5-carbon ring. In prostacyclins, this ring is conjoined to another oxygen-containing ring. In thromboxanes the ring becomes a 6-member ring with one oxygen. Production of PGE2 in bacterial and viral infections appear to be stimulated by certain cytokines, e.g., [interleukin-1](/source/interleukin-1). {{cite web | author = University of Kansas Medical Center | year = 2004 | title = Eicosanoids and Inflammation | url = http://classes.kumc.edu/som/bioc801/small_group/eicosanoids/eicosanoids-2004.pdf | access-date = 2007-01-05 | archive-url = https://web.archive.org/web/20050516013327/http://classes.kumc.edu/som/bioc801/small_group/eicosanoids/eicosanoids-2004.pdf | archive-date = 2005-05-16 | url-status = dead }} ==See also== * [Prostaglandin](/source/Prostaglandin) * [Prostaglandin receptors](/source/Prostaglandin_receptors) * [Prostanoid receptor](/source/Prostanoid_receptor)s * [Essential fatty acid](/source/Essential_fatty_acid) * [Isoprostane](/source/Isoprostane) * [Prostacyclin](/source/Prostacyclin) ==References== {{Reflist}} {{Eicosanoids}} {{Prostanoidergics}} Category:Prostaglandins Category:Eicosanoids {{biochem-stub}} --- Adapted from the Wikipedia article [Prostanoid](https://en.wikipedia.org/wiki/Prostanoid) by Wikipedia contributors ([contributor history](https://en.wikipedia.org/wiki/Prostanoid?action=history)). 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