Subodh kumar senior scientist,senior scientist, division of animal geneticsdivision of animal genetics indian veterinary research institute, izatnagarindian veterinary research institute, izatnagar 2. Streptococcus pneumoniae anchor to activated human cells by the receptor for platelet activating factor. Plateletactivating factor and related lipid mediators annual. To generate paf, phospholipase a 2 removes fatty acid in the sn2 position of the estertype membrane phospholipid, followed by acetylation. Plateletactivating factor pafantagonists of natural. Plateletactivating factor an overview sciencedirect. Forty years since the structural elucidation of plateletactivating. The structure and function of plateletactivating factor. Platelet activating factor paf is a low molecular weight, etherlinked phospholipid originally identified as a soluble factor, released from sensitized rabbit basophils during ige anaphylaxis, that was capable of aggregating rabbit platelets 1, 2.
Plateletactivating factor paf is a potent, bioactive phospholipid that acts on multiple cells and tissues through its g proteincoupled receptor gpcr. Plateletactivating factor and the release of a platelet. Paf is formed by a smaller number of cell types than the eicosanoids, mainly leukocytes, platelets, and endothelial cells. The bioactivity of paf is effectively and tightly regulated by paf. Gray matter degeneration contributes to progressive disability in multiple sclerosis ms and can occur out of proportion to measures of white matter disease. Pdf on nov 1, 1990, s m prescott and others published plateletactivating factor find, read and cite all the research you need on. Platelet activating factor acetylglyceryletherphosphorylcholine. Because lipoprotein levels decrease after myocardial infarction, a possible reduction was suspected to occur in plasma. Paf is a potent phospholipid activator and mediator of many leukocyte functions, including platelet aggregation, inflammation, and anaphylaxis. Egido 0 2 0 fundacion jimenez diaz, avda reyes catolicos 2, 28040 madrid, spain 1 pediatric renal unit, hospital 12 octubre, madrid, spain 2 renal unit, fundacion. Elisa kit for platelet activating factor receptor pafr. Because platelet activating factor paf participates in the inflammatory process, the effect of a pafspecific antagonist, bn52021, on the ovulatory response was tested in rats. Plateletactivating factor paf is a lipid mediator involved in several allergic reactions. Platelet activating factor paf at 100nm induced a biphasic calcium response in microglia culture.
Plateletactivating factor paf is a mediator of inflammation that is implicated in cvd and hiv1 infection, shares mechanisms of immune activation with oxidized lipoproteins, and its receptor pafr is also found on tcells and macrophages. Paf was originally described as a soluble factor in blood, so it is apparent that some cells secrete it following synthesis. Emphasis is given on recent results about a new class of the socalled metalbased inhibitors of paf. Coagulation factors, phosphatidylserine, platelet receptors, thrombin summary platelet activation and blood coagulation are complementary, mutually dependent processes in haemostasis and thrombosis. Pdf plateletactivating factor and related lipid mediators. Later observations by siraganuan and osler observed the existence of a diluted substance that had the capacity to cause platelet activation.
Informations about elisa kit for platelet activating factor receptor pafr sec753hu5. Platelet activating factor is a potent biological mediator that exerts its effects in a variety of cells and tissues. If a firm is not confident in its ability to collect on its credit sales, it may sell the right to receive payment to the factor at a discount. Slideshare uses cookies to improve functionality and performance, and to provide you with relevant advertising. Platelet activating factor is a biologically potent phospholipid that may mediate cell damage in patients with myocardial ischemia. Plateletactivating factor receptor pafr is a g q g 11coupledprotein receptor that has a role in a wide range of biological processes such as vasodilation, superoxide formation, cell proliferation, angiogenesis and regulation of the inflammatory response. Platelet activating factor paf, 10alkyl2acetylsnglycero3phosphocholine is a potent mediator of inflammation that causes neutrophil activation, increased vascular permeability, vasodilation, and bronchoconstriction in addition to platelet activation.
The synthesis, transport, and degradation of paf are tightly regulated, and the biochemical basis for many of these processes has been elucidated in recent years. In 1972, the term platelet activating factor paf was coined by benveniste, henson, and cochrane. Platelet activating factor paf is a potent phospholipid mediator, which has previously reported biological activities in bc progression and osteoclast differentiation by activating its receptor. Pafr is linked to multiple intracellular signaling pathways, including the p38 mapk and pi 3k pathways, through increasing. Factor a third party that buys a firms accounts receivable. Variation in plasma plateletactivating factor degradation. The involvement of platelet activating factor in ovulation. Platelet activating factor binds to a unique gprotein coupled seven transmembrane receptor and triggers multiple intracellular signaling pathways. It is released from multiple cells of the immune system, such as eosinophils, neutrophils, and mast cells, and also exerts its effect on most of them upon specific binding to its receptor, becoming a pleiotropic mediator.
Plateletactivating factor paf is a phospholipid with potent, diverse physiological actions, particularly as a mediator of inflammation. Plateletactivating factor is identified as 1oalkyl2acetylsnglycero3phosphocholine 12. Plateletactivating factor paf is a potent inflammatory mediator that mimics many of the features of asthma, including eosinophil recruitment and activation and induction of ahr. Abstract plateletactivating factor paf is a phospholipid with potent, diverse physiological actions, particularly as a mediator of inflammation. Plateletactivating factor receptors mediate excitatory. Paf is not stored but is rapidly generated via enzymatic acetylation of the precursor 1 o hexadecyl2hydroxy sn glycero3phosphocholine lysopaf. Files are available under licenses specified on their description page. The ginkgolide, a unique c 20 cage molecule, is a naturally occurring plateletactivating factor paf antagonist braquet 1987. Paf is a potent mediator of anaphylaxis and inflammation and is also implicated in shock, graft rejection, renal diseases. Jcm free fulltext plateletactivating factor paf in. Kay department ofallergyandclinicalimmunology, cardiothoracicinstitute, bromptonhospital, london, sw36hp, unitedkingdom abstract plateletactivating factor pafacether, an inflammatory me diator with a wide range ofbiological activities. Streptococcus pneumoniae anchor to activated human cells. Plateletactivating factor acetylhydrolases pafahs, ec 3.
Bn52021, administered locally, inhibited follicle rupture in rats stimulated to ovulate with human chorionic gonadotropin hcg. Plateletactivating factor paf in allergic rhinitis. Plateletactivating factor the journal of lipid research. Plateletactivating factor and related lipid mediators springerlink. Many of the actions of paf can be mimicked by structurally related phospholipids that are. Paf is a unique and novel signalling phospholipid that has pleiotrophic biological properties in addition to platelet activation and is produced by a variety of cell types snyder, 1987. Sudden release of platelet activating factor paf into the circulation can cause hypotension, tachycardia, and circulatory collapse. At first, results of organic compounds natural and synthetic ones and specific and nonspecific as inhibitors of paf are reported. Plateletactivating factor paf financial definition of.
Paf is a phospholipid 10alkyl2acetylsnglycero3phosphorylcholine that has been implicated as a mediator in diverse pathologic processes. Follicle rupture during ovulation is associated with inflammationlike changes. In plasma, its inactivation to lyso platelet activating factor is catalyzed by a specific, lipoproteinassociated acetylhydrolase. The plateletactivating factor receptor is a gprotein coupled receptor which binds platelet activating factor the paf receptor shows structural characteristics of the rhodopsin mim 180380 gene family and binds platelet activating factor paf. All structured data from the file and property namespaces is available under the creative commons cc0 license. Pdf plateletactivating factor paf is a phospholipid with potent, diverse physiological actions, particularly as a mediator of inflammation. Plateletactivating factor paf is a phospholipid that was discovered as a platelet agglutinating factor derived from rabbit basophils and as a depressor substance derived from the renal medulla. The factor then assumes the credit risk associated. The structure of paf was later elucidated by demopoulos, pinckard, and hanahan in 1979. However, we found that the paf made by endothelial cells is. Paf is considered a potential relevant mediator in allergic rhinitis, with a key. The distinguishing property of pafahs is their unique substrate specificity they act on the phospholipid. It is also involved in changes to vascular permeability, the oxidative burst, chemotaxis of leukocytes, as well as augmentation of.
Due to its role, it has been also considered as a hormone or a primitiveuniversal cellular biological regulator 12. Plateletactivating factor is a ubiquitous and potent lipid inflammatory mediator 12. Rupatadine, a new potent, orally active dual antagonist of. Platelet activating factor paf is a lipid mediator involved in several allergic reactions.
Plateletactivating factor, also known as paf, pafacether or agepc acetylglyceryletherphosphorylcholine, is a potent phospholipid activator and mediator of many leukocyte functions, platelet aggregation and degranulation, inflammation, and anaphylaxis. Urinary excretion of plateletactivating factor in human. To further examine this response, we performed detailed studies of cardiovascular function after paf administration. Opposing effects of plateletactivating factor and lyso.
Role of plateletactivating factor paf in the initiation. Plateletactivating factor paf is a potent inflammatory mediator that mimics many of the features of asthma, including eosinophil recruitment and activation and. Plateletactivating factor and related lipid mediators. Plateletactivating factor paf is a proinflammatory lipid mediator possessing a unique 1oalkyl glycerophospholipid gpc backbone. Forty years since the structural elucidation of platelet. It has a role as a betaadrenergic antagonist, an antihypertensive agent, a bronchoconstrictor agent.
Role of platelet activating factor paf in the initiation of the decidual reaction in the rat in reproduction. Platelets interact with several coagulation factors, while the coagulation product thrombin is a potent platelet activating agonist. Plateletactivating factor paf, 10alkyl2acetylsn glycero3phosphocholine is a potent biological mediator that exerts its effects in a variety of cells and. Pdf enzymatic pathways for plateletactivating factor, related alkyl. Pdf cardiovascular effects of plateletactivating factor. Factor a financial institution that buys a firms accounts receivable and collects the accounts. Plateletactivating factor an overview sciencedirect topics. Plateletactivating factor paf is the commonly used name for a group of potent.
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