wiktionary antagonist antagonistic antagonists An antagonist is a character opposing the protagonist in literature. Antagonist may also refer to Antagonist muscle , a muscle type Receptor antagonist , a class of drugs that bind to but do not trigger a receptor Antagonist A.D. , a New Zealand metalcore band The Antagonists , a 1971 novel by Ernest K. Gann about the siege of Masada Antagonist , a book in Childe Cycle by Gordon R. Dickson and David W. Wixon Antagonist album Antagonist album , the debut album of the german Metalcore band Maroon HMS Antagonist See also Antagonism disambiguation Agonist , a chemical that binds to a receptor of a cell and triggers a response by that cell disambiguation ca Antagonista cs Antagonista de Antagonist et Antagonist fr Antagoniste he lt Antagonistas nl Antagonist pt Antagonista sk Antagonista sv Antagonist tr Antagonist ... more details
About the literary term the pharmacological term receptor antagonist other uses An antagonist from Greek language Greek antagonist s , opponent, competitor, enemy, rival ref cite web url http www.etymonline.com index.php?search antagonist&searchmode none title Antagonist publisher Online Etymology Dictionary accessdate 28 November 2010 ref is a character, group of characters, or institution , that represents the opposition against which the protagonist must contend. In other words, A person, or a group of people who oppose the main character, or the main characters. ref http contemporarylit.about.com cs literaryterms g antagonist.htm About.com, Literature Contemporary Antagonist. Online. October 18, 2007. ref In the classic style of stories wherein the action consists of a hero fighting a villain enemy , the two can be regarded as protagonist and antagonist, respectively. ref The antagonist may not always be a person or persons. In some cases an antagonist may be a force, such as a tidal wave that destroyed a city, or a storm that is causing havoc, or even the conditions in a certain area that is causing a problem. An antagonist also may or may not create obstacles for the protagonist ... The Elements of Literature publisher rscc.cc.tn.us ref The antagonist may also represent a major threat ... him or her. Examples in both film and theatre include Sauron , the main antagonist in The Lord of the Rings , who constantly battles the series protagonists, and Tybalt , an antagonist in Romeo ... da Antagonist de Antagonist Literatur es Antagonista literatura eu Antagonista fr Antagoniste litt rature ko hr Antagonist id Antagonis it Antagonista he mk ms Antagonis nl Antagonist narratologie ja no Antagonist pl Antagonista pt Antagonista literatura ro Antagonist ru sq Antagonisti simple Antagonist sk Antagonista literat ra fi Antagonisti sv Antagonist narratologi tr Antagonist terim uk ... more details
A competitive antagonist is a receptor antagonist that binds to a Receptor biochemistry receptor but does not activate the receptor. The antagonist will compete with available agonist for receptor binding site s on the same receptor. Sufficient antagonist will displace the agonist from the binding sites, resulting in a lower frequency of receptor activation. Presence of a competitive antagonist will shift an agonism dose response curve to the right. ref name prism http www.curvefit.com schild.htm Doseresponse curves in the presence of antagonists Bot generated title ref A Schild plot for a competitive antagonist will have a slope equal to 1, and the X intercept and Y intercept will each equal the dissociation constant of the antagonist. ref name prism A competitive antagonist can be reversible competitive antagonist or irreversible competitive antagonist . References reflist Category Pharmacology Pharma stub Pharmacology ca Antagonista competitiu de Kompetitiver Antagonist es Antagonista competitivo sr Kompetitivni antagonist ... more details
orphan date February 2009 In pharmacology the term agonist antagonist is used to refer to a drug which exhibits some properties of an agonist a substance that fully activates the neuronal receptor that it attaches to and some properties of an antagonist medial antagonist a substance that attaches to a receptor but does not activate it or if it displaces an agonist at that receptor it seemingly deactivates it thereby reversing the effect of the agonist . The best known agonists and antagonists are opioids morphine is an agonist to opioid receptors while naloxone Narcan is an antagonist. References Unreferenced date July 2008 Category Pharmacology ... more details
About the biochemistry term other uses Antagonistdisambiguation File Antagonist 2.png thumb Antagonists ... produced by a receptor agonist coupling. A receptor antagonist is a type of Receptor biochemistry ... of the receptor s activity. Antagonist activity may be reversible or irreversible depending on the longevity of the antagonist receptor complex, which, in turn, depends on the nature of antagonist ... pmid 12690954 doi 10.1080 10606820214640 ref The term antagonist was originally coined to describe ... 1866283 ref The biochemical definition of a receptor antagonist was introduced by Ariens ref cite journal ... article. ref in the 1950s. The current accepted definition of receptor antagonist is based on the Receptor ... activation and receptor theory and the biochemical definition of a receptor antagonist continues ... . In functional antagonist assays, a dose response curve measures the effect of the ability ... The potency of an antagonist is usually defined by its IC50 IC sub 50 sub value. This can be calculated for a given antagonist by determining the concentration of antagonist needed to elicit half ... 10.1111 j.1365 2885.2004.00620.x ref The lower the IC sub 50 sub the greater the potency of the antagonist ... doi 10.1038 nrd1500 ref Affinity The affinity of an antagonist for its binding site K sub i sub , i.e. .... The affinity of an antagonist can be determined experimentally using Schild regression or for competitive ... of a competitive antagonist as determined on a dose response curve. Altering the amount of antagonist ... dose ratio 1 versus the log concentration of antagonist for a range of antagonist concentrations ... the line cuts the x axis on the regression plot. Whereas, with Schild regression, antagonist ... by the Cheng Prusoff factor used to calculate the K sub i sub affinity constant for an antagonist ... Competitive Competitive antagonist s also known as surmountable antagonists reversibly bind to receptors ..., an antagonist will block agonist binding. The level of activity of the receptor will be determined ... more details
GABA antagonists are drugs which inhibit the action of GABA . In general these drugs produce stimulant and convulsant effects, and are mainly used for counteracting overdose of sedative drugs. Examples include Bicuculline and Metrazol , and the benzodiazepine GABA A receptor GABA sub A sub receptor antagonist Flumazenil . Also Thujone has properties of GABA sub A sub receptor antagonist. External links MeshName GABA antagonists Receptor agonists and antagonists GABA agonists and antagonists Category GABA antagonists biochem stub da GABA antagonist ... more details
For the use of hormone antagonists in cancer , see hormonal therapy oncology A Hormone antagonist is a specific type of receptor antagonist which acts upon hormone s. External links MeshName Hormone antagonists Hormone antagonists biochemistry stub Category Hormonal agents Category Receptor antagonists ... more details
An Adrenergic antagonist is a pharmaceutical substance that acts to inhibit the action of the adrenergic receptor s. It is thus a type of sympatholytic . It has the opposite effect as adrenergic agonist s. More specifically, they can be divided into Alpha blocker s Beta blocker s Structure Activity Relationship If the amine on the Adrenergic agent has a substituent bigger than a tertiary butyl, then the compound becomes an adrenergic antagonist. ref http pharmaxchange.info notes medicinal chemistry adrenergics cholinergics.html Medicinal Chemistry of Adrenergics and Cholinergics ref References Reflist External links MeshName Adrenergic antagonists Antihypertensives and diuretics Receptor agonists and antagonists Alpha blockers DEFAULTSORT Adrenergic Antagonist Category Antihypertensive agents cardiovascular drug stub es Antagonista adren rgico ... more details
About the type of muscle other uses Antagonist Unreferenced date December 2009 Most muscles work in pairs, and when a muscle works it needs to have an Agonist muscle agonist and an antagonist , unless the muscle s natural state is opposite to that which is produced by the muscle, example Sphincter ani externus muscle . antagonistic pairs are located in opposite sides of a joint or bone. An antagonist is a classification used to describe a muscle that acts in opposition to the specific movement generated by the Agonist muscle agonist and is responsible for returning a limb to its initial position. Antagonistic pairs Antagonistic muscles are found in pairs called antagonistic pairs. These consist of an extensor muscle , which opens the joint i.e. increasing the angle between the two bones , flexor muscle , which does the opposite to an extensor muscle .lax Antagonistic pairs are needed in the body because muscles can only exert a pulling force, and can t push themselves back into their original positions. An example of this kind of muscle pairing is the biceps brachii and triceps brachii . When the biceps brachii biceps are contracting, the triceps are relaxed, and stretches back to its original position. The opposite happens when the triceps contract. Another example on antagonistic pairs abductor and adductor muscles. DEFAULTSORT Antagonist Muscle Category Muscular system ca M scul antagonista de Antagonist Muskel es M sculo antagonista fr Antagoniste anatomie nl Agonistische en antagonistische spieren ja pt Antagonista m sculo fi Vastavaikuttajalihakset th ... more details
Infobox album See Wikipedia WikiProject Albums Name Antagonist Type studio Artist Maroon band Maroon Cover Antagonist album .jpeg Released 2002 ref cite web url http www.metal archives.com release.php?id 59776 title Encyclopaedia Metallum The Metal Archives Maroon Antagonist publisher The Metal Archives date 2004 10 13 accessdate 2012 01 14 ref Recorded Genre Metalcore Length 38 33 Label Catalyst Records Producer Last album This album Antagonist br 2002 Next album Endorsed By Hate album Endorsed By Hate br 2004 Antagonist is the debut album of the Germans german metalcore band Maroon band Maroon . Track listing Tempest I 01 58 The Beginning of the End 04 05 An End Like This 03 57 Shadow of the Vengeance 03 41 Tempest II 00 19 Drowning 04 37 Still Believe In What Has Fallen Apart 05 01 Beneath The Ashes 03 40 Stillborn 05 29 What Remains 02 31 Declaration 03 15 References Reflist Category 2002 debut albums Category Maroon albums ... more details
A serotonin antagonist is a drug used to inhibit the action at serotonin receptor s. Many of the most important medications of this class selectively act at the 5 HT3 receptor , and thus are known as 5 HT3 antagonist s. However, other drugs such as ketanserin act upon other types of serotonin receptors. Antagonists of the 5 HT2A 5 HT sub 2A sub receptor are sometimes used as atypical antipsychotic s, with the typical antipsychotic s being purely dopamine antagonist s. Ketanserine blocks 5 HT2A 5 HT sub 2A sub , 5 HT2C 5 HT sub 2C sub and Alpha 1 Adrenoreceptors . Ondansetron , Dolansetron and Granisetron are 5 HT3 receptor antagonist. They are efficacious in treating chemotherapy induced emesis citation needed date April 2012 . Clozapine blocks 5 HT2A 5 HT sub 2A sub , 5 HT2C 5 HT sub 2C sub and D4 receptors . Quetiapine blocks 5 HT2A 5 HT sub 2A sub , 5 HT1A 5 HT sub 1A sub , D1 2, HI, Alpha 1 Adrenoreceptors . Methsergide is a 5 HT2A 5 HT sub 2A sub antagonist and nonselective 5 HT1 5 HT sub 1 sub receptor blocker. It causes retroperitoneal fibrosis and mediastinal fibrosis citation needed date April 2012 . Cyproheptadine blocks 5 HT2A 5 HT sub 2A sub , HI and is a mild anticholinergic . Pizotifen is a 5 HT2C 5 HT sub 2C sub antagonist, H1 blocker and anticholinergic useful in migraine prophylaxis citation needed date April 2012 . See also Serotonin receptor agonist External links MeshName Serotonin Antagonists MeshPharmaList 82012702 Receptor agonists and antagonists Serotonergics Category Serotonin antagonists nervous system drug stub ... more details
An irreversible antagonist is a type of antagonist pharmacology antagonist that binds permanently to a Receptor biochemistry receptor , either by forming a covalent bond to the active site, or alternatively just by binding so tightly that the rate of dissociation is effectively zero at relevant time scales. ref Goodman and Gilman s Manual of Pharmacology and Therapeutics. 11th edition, 2008 . p25. ISBN 0071443436 ref This permanently deactivates the receptor and is usually followed by rapid Receptor mediated endocytosis internalisation and recycling of the non functional receptor protein. Irreversible enzyme inhibitors that act similarly are clinically used and include drugs such as aspirin, omeprazole and monoamine oxidase inhibitors. ref Rang and Dale s Pharmacology. 6th edition, 2007 . p19. ISBN 0443069115 ref Examples Naloxazone Phenoxybenzamine See also Irreversible agonist Irreversible inhibition Irreversible enzyme inhibitor References reflist Pharmacology Category Receptor antagonists pharmacology stub ... more details
Refimprove date April 2009 cleanup date April 2009 Infobox musical artist name Antagonist A.D. background group or band origin Auckland, New Zealand genre Metalcore label Trial & Error Records Trial & Error br Elevenfiftyseven website http www.antagonistad.com Antagonist A.D. current members Sam Crocker br Kris Boozey Bosman br Israel McDean br Matthew Livingstone past members Sean O Kane Connelly br Brendan Wishnowsky br Joshua Moffitt br Ross McDougall Antagonist A.D. are a New Zealand metalcore band. History Formation and S T Demo 2005 Antagonist A.D started in 2005 by vocalist Sam Crocker and bassist Joshua Moffitt. The intention was to create a fast heavy metallic hardcore band in the vein ... to European bands Arkangel and Maroon. Known then as simply Antagonist feeling the bands shared ... greats such as DSM, Balance and The Bleeders . ref http www.elevenfiftyseven.com bands.php Antagonist ... by Melbourne based label Trial & Error Records . ref http www.myspace.com trialanderrorhardcore Antagonist ... Heart, Antagonist & Break Even Tour Punknews.org Bot Generated title ref Following the tour the band ... show. We Are The Dead 2008&ndash 2010 Antagonist A.D. released its Second Studio album in Australia ... looming on the horizon the band released We Are The Dead under the name Antagonist A.D. adding the suffix to avoid confusion with an American band using the name Antagonist already. ref name We are Antagonist from the USA, NOT from New Zealand Cite web last first title We are Antagonist from the USA, NOT from New Zealand publisher myspace.com antagonist date url http www.myspace.com antagonist blog ... Reflist http www.antagonistad.com Antagonist A.D. Official Website External links http www.myspace.com antagonistad Antagonist A.D. Myspace Page http www.twitter.com antagonistad Antagonist A.D. Twitter Page http antagonistad.bigcartel.com Antagonist A.D. Big Cartel Page http www.antagonistad.com Antagonist A.D. Website blockquote Category Musical groups established in 2005 Category New Zealand ... more details
Image Potassium sparing diuretics2.svg thumb Skeletal formula e of the aldosterone antagonists Aldosterone antagonist refers to diuretic drugs which receptor antagonist antagonize the action of aldosterone at mineralocorticoid receptor s. This group of drugs is often used as adjunctive therapy, in combination with other drugs, for the management of chronic heart failure . Spironolactone , the first member of the class, is also used in the management of hyperaldosteronism including Conn s syndrome and female hirsutism . Mechanism of Action Aldosterone antagonists are, as the name suggests, receptor antagonist s at the mineralocorticoid receptor . Antagonism of these receptors inhibits sodium resorption in the collecting duct of the nephron in the kidneys. This interferes with sodium potassium exchange, reducing urinary potassium excretion and weakly increasing water excretion diuresis . ref Rossi S, editor. Australian Medicines Handbook 2006. Adelaide Australian Medicines Handbook 2006. ref In congestive heart failure , they are used in addition to other drugs for additive diuretic effect, which reduces edema and the heart cardiac workload. Examples Members of this class in clinical use include Spironolactone Eplerenone more specific than spironolactone on target, but also more expensive Canrenone canrenoate potassium Prorenone prorenoate potassium Mexrenone mexrenoate potassium See also Potassium sparing diuretic ATC code C03 C03DA Aldosterone antagonists References references External links MeshName Aldosterone Antagonists MeshPharmaList 82000451 Hormone antagonists Diuretics Category Aldosterone antagonists Category Potassium sparing diuretics Category Steroids es Antagonista de la aldosterona pl Blokery receptora aldosteronowego ... more details
For the New Zealand band once known as Antagonist, see Antagonist A.D. . Infobox musical artist See Wikipedia WikiProject Musicians name Antagonist background group or band alias origin Whittier, California ... This City website http www.myspace.com antagonist www.myspace.com antagonist current members ... Salem br David Zamora br Marcus Hill Antagonist is an American metalcore band from Whittier, California ... 1998 2006 Antagonist began when middle school friends Carlos Garcia, Marcus Hill and David ... Wunty and His Band of Merry Elephants, but they agreed on Antagonist after it was suggested by Zamora ... EP 2002 , Live at the Showcase EP 2003 , and Intended to Hurt or Wound EP 2003 . Antagonist parted ... of Discord 2005 . This would be their last self released effort. 2005 was also the year Antagonist ... of Plague in the Winter of 2005 2006. In 2006, Antagonist signed a 1 album deal with Dwell Records. ref Antagonist signs w Dwell Records Cite web last first title Antagonist signs w Dwell ... ref ref An Envy Of Innocence Cite web last first title Antagonist Signs With Dwell Records publisher ... of 2007, Antagonist were signed to Prosthetic Records. ref Prosthetic Records signs Antagonist Cite web last first title Prosthetic Records signs Antagonist publisher Lambgoat.com date February 2 .... ref Matt Lopez Cite web last first title Antagonist guitarist leaves band publisher Lambgoat.com date January 7, 2009 url http www.lambgoat.com news view.aspx?id 12043 ref Antagonist hired long ... first title ANTAGONIST INTRODUCES NEW GUITARIST, POSTS NEW SONG publisher Prosthetic Records date March ... guitar duties and took over the roll of bassist for Antagonist. The new lineup played their first show in September 2009. ref Nick Reyes Cite web last first title Antagonist announces new bassist publisher ... Antagonist returned to the studio in the Spring of 2010 to record its second Prosthetic full length ... web last first title ANTAGONIST Album Streaming Now Hear World In Decline Courtesy of Hails And Horns ... more details
A histamine antagonist commonly called an antihistamine is a pharmaceutical drug that inhibits the action of histamine by blocking it from attaching to histamine receptor s or it may inhibit the enzymatic activity of histidine decarboxylase, catalyzing the transformation of histidine into histamine atypical antihistaminics . Antihistamines are commonly used for the relief of Protein allergy allergies caused by intolerance of proteins. ref Sicherer, Scott H. M.D., Understanding and Managing Your Child s Food Allergy. Baltimore The Johns Hopkins University Press, 2006 ISBN 0801884926. ref Clinical effects Histamine s produce increased vascular permeability, causing fluid to escape from capillaries into tissues, which leads to the classic symptoms of an allergic reaction a runny nose and watery eyes. Antihistamines suppress the histamine induced Cutaneous condition Morphology wheal response swelling and Vasodilation flare response vasodilation by blocking the binding of histamine to its receptors on nerves, vascular smooth muscle, glandular cells, endothelium, and mast cells. They exert a competitive antagonism to histamines. Itching and sneezing are suppressed by antihistamine blocking of H1 receptor s on nasal sensory nerves. ref cite journal pmid 9042073 title Appraisal of the validity ... 2 sub receptor antagonists H sub 1 sub receptor antagonists Main H1 antagonist l1 H sub 1 sub antagonist ... inverse agonist s at the histamine H sub 1 sub receptor, rather than receptor antagonist antagonists ... Triprolidine H sub 2 sub receptor antagonists Main H2 antagonist l1 H sub 2 sub antagonist ... receptor antagonist antagonists . H sub 2 sub histamine receptors, found principally in the parietal ... antagonists Main H3 antagonist l1 H sub 3 sub antagonist Examples A 349,821 ABT 239 Ciproxifan Clobenpropit ... Reflist External links MeshName Histamine antagonist Antihistamines Histaminergics Neuromodulation DEFAULTSORT Histamine Antagonist Category Antihistamines ar ca Antihistam nic ... more details
The Antagonist Art Movement is a cultural movement formed in New York, New York in 2000. The group grew ... and resources. The Antagonist Movement has worked with more than 3,000 artists from around the world over the past 11 years. Overview Antagonist activities have included public gatherings, demonstrations ... East Side , the Antagonist Movement has participants in other US cities, Europe and South America. Influenced by the punk rock and pop art and by the Dada movement , the Antagonist Movement seeks ... of the Antagonist Movement while working in bars in the Lower East Side. They wanted to create an event ... night have included Bryan Middleton, Richard Allen and Brother Mike Cohen. Minsker took the helm of the Antagonist ... between 8 pm and 9 pm and stayed up until 2 am. The Antagonist took a 20 commission on art ... each other. ref cite web url http animalnewyork.com 2006 05 the antagonist movement ignite title ... from 8 pm to 10 pm, free live shows were performed in the back of Niagara bar under the banner of the Antagonist ... also composed music for two Antagonist films, This Is Berlin, Not New York and The Dolls of Lisbon ... of the books published by the Antagonist Movement. Currently the Monday music night has moved to Motor ... on the theme. Themes are determined by a combination of curators, artists, and members of the Antagonist ... was exhibited in the front room of Niagara bar and is featured in the Antagonist movie Mark of the Ninja. Gallery shows From time to time, the Antagonist Movement holds group art shows in small commercial ..., the Mindy Wyatt Gallery presented a curated group show of select artists of the Antagonist Art Movement ... of Lisbon The Antagonist Art Movement combined the efforts of artists all over the world to put together ... in 2007, the Antagonist began actively developing cultural exchanges with artists in other countries. Antagonist artists traveled to Germany in 2007 and to Portugal in 2010. The Antagonists are planning a group trip to Ecuador in 2013. In addition, the Antagonist Movement is actively seeking contacts ... more details
An opioid antagonist is a receptor antagonist that acts on opioid receptor s. Naloxone and naltrexone are commonly used opioid antagonist drugs which are competitive antagonist s that bind to the opioid receptors with higher affinity than agonists but do not activate the receptors. This effectively blocks the receptor, preventing the body from responding to opiates and endorphins. Some opioid antagonists are not pure antagonists but in fact do produce some weak opioid partial agonist effects, and can produce analgesic effects when administered in high doses to opioid naive individuals. Examples of such compounds include nalorphine and levallorphan . However the analgesic effects from these drugs are limited and tend to be accompanied by dysphoria , most likely due to action at the kappa opioid receptor . As they induce opioid withdrawal effects in people who are taking, or have recently used, opioid full agonists, these drugs are considered to be antagonists for practical purposes. The weak partial agonist effect can be useful for some purposes, and has previously been used for purposes such as long term maintenance of former opioid addicts using nalorphine, however it can also have disadvantages such as worsening respiratory depression in patients who have overdosed on non opioid sedatives such as Alcoholic beverage alcohol or barbiturates . Naloxone on the other hand has no partial agonist effects, and is in fact a partial inverse agonist at mu opioid receptors, and so is the preferred ... Cyprodime is a selective mu opioid receptor antagonist Naltrindole is a selective delta opioid receptor antagonist Norbinaltorphimine is a selective kappa opioid receptor antagonist Other selective ... House episode Skin Deep , opioid antagonist drugs were administered in order to completely remove ... partial agonist and antagonist actions External links David S, Lancaster T, Stead LF. http www.cochrane.org ... References Reflist DEFAULTSORT Opioid Antagonist Category Opioid antagonists de Opioidantagonist ... more details
A Cholecystokinin antagonist is a specific type of receptor antagonist which blocks the receptor sites for the peptide hormone Cholecystokinin Cholecystokinin receptor CCK . There are two subtypes of this receptor known at present, defined as cholecystokinin A receptor CCK sub A sub and cholecystokinin B receptor CCK sub B sub also called CCK 1 and CCK 2 . CCK sub A sub is mainly expressed in the small intestine, and is involved in the regulation of enzyme secretion by the pancreas, secretion of gastric acid in the stomach, intestinal motility and signalling of satiety fullness . CCK sub B sub is expressed mainly in the central nervous system, and has functions relating to anxiety and the perception of pain. ref cite journal pmid 15533776 year 2004 last1 Rehfeld first1 JF title Clinical endocrinology and metabolism. Cholecystokinin volume 18 issue 4 pages 569 86 doi 10.1016 j.beem.2004.07.002 journal Best practice & research. Clinical endocrinology & metabolism ref Antagonists for the CCK receptors can thus have multiple functions in both the gut and brain. The best known CCK antagonist is the non selective antagonist proglumide , which blocks both CCK sub A sub and CCK sub B sub , and was originally developed for the treatment of stomach ulcers. This action derived from its blockade of CCK sub A sub in the gut and consequent reduction in secretion of gastric acid, however an interesting side effect of proglumide was found, namely that it increases the analgesic effects of opioid ... A first3 G first4 J first5 M first6 E first7 D ref However by far the main focus of CCK antagonist research ... of non peptide CCK2 receptor agonist and antagonist ligand volume 7 issue 12 pages 1195 204 journal ... are also expressed in the brain to some extent, and interestingly IQM 95333, an antagonist selective ... L pez title Pharmacological evaluation of IQM 95,333, a highly selective CCKA receptor antagonist ... Category Cholecystokinin antagonists sr Holecistokininski antagonist ... more details
An orexin antagonist is a drug that inhibits the effect of orexin by acting as a receptor antagonist of the orexin receptor . Potential applications include treatment of sleep disorders such as insomnia . ref name pmid18673167 cite journal author Roecker AJ, Coleman PJ title Orexin receptor antagonists medicinal chemistry and therapeutic potential journal Curr Top Med Chem volume 8 issue 11 pages 977 87 year 2008 pmid 18673167 doi ref ref name pmid21170610 cite journal author Cao M, Guilleminault C title Hypocretin and its emerging role as a target for treatment of sleep disorders journal Curr Neurol Neurosci Rep volume 11 issue 2 pages 227 34 year 2011 month April pmid 21170610 doi 10.1007 s11910 010 0172 9 url ref Examples Almorexant , development of the drug was abandoned in January 2011 SB 334,867 , has been shown to produce sedative and anorectic effects in animals, ref name pmid11298806 cite journal author Rodgers RJ, Halford JC, Nunes de Souza RL, Canto de Souza AL, Piper DC, Arch JR, Upton N, Porter RA, Johns A, Blundell JE title SB 334867, a selective orexin 1 receptor antagonist, enhances behavioural satiety and blocks the hyperphagic effect of orexin A in rats journal Eur. J. Neurosci. volume 13 issue 7 pages 1444 52 year 2001 month April pmid 11298806 doi 10.1046 j.0953 816x.2001.01518.x ref SB 408,124 SB 649,868 , in development for potential use in sleep disorders Suvorexant , in development for potential use in sleep disorders TCS OX2 29 References reflist Category Orexin antagonists ... more details
A Prostaglandin antagonist is a hormone antagonist acting upon prostaglandin . NSAID s inhibit cyclooxygenase and reduce prostaglandin synthesis. Corticosteroid s inhibit phospholipase A sub 2 sub production by boosting production of lipocortin , an inhibitor protein. Relatively new drugs, known as COX 2 selective inhibitor s or coxibs, are used as specific inhibitors of COX 2. The development of these drugs allowed the circumvention of the negative gastrointestinal effects while effectively reducing inflammation. Adverse effects Both NSAIDs and Coxibs can raise the risk of myocardial infarction , when taken on a chronic basis for at least 18 months. One emerging hypothesis that may explain the cardiovascular effects is that coxibs create an imbalance in circulating TxA2 thromboxane and PGI2 prostacyclin levels. An increased in the ratio of TxA2 PGI2 could lead to increased platelet aggregation and dysregulation of platelet homeostasis. ref Cheng Y et al., Role of prostacyclin in the cardiovascular response to thromboxane A2. Science 2002 296 539 51. PMID 11964481. ref See also Mechanism of action of aspirin References references External links MeshName Prostaglandin antagonists Hormone antagonists Biochemistry stub Category Corticosteroids Category Receptor antagonists Category Prostaglandins ... more details
DISPLAYTITLE H sub 2 sub antagonist Image Cimetidine xtal 3D balls.png thumb Ball and stick model of cimetidine , the prototypical H sub 2 sub receptor antagonist. The H sub 2 sub receptor antagonists are a class of medication drugs used to block the action of histamine on parietal cell s in the stomach , decreasing the production of acid by these cells. H sub 2 sub antagonists are used in the treatment of dyspepsia , although they have been surpassed in popularity by the more effective ref Eriksson S, L ngstr m G, Rikner L, Carlsson R, Naesdal J. Omeprazole and H2 receptor antagonists in the acute treatment of duodenal ulcer, gastric ulcer and reflux oesophagitis a meta analysis published correction appears in Eur J Gastroenterol Hepatol. 1996 8 192 . Eur J Gastroenterol Hepatol. 1995 7 467 475 ref proton pump inhibitor s. In the United States, all four Food and Drug Administration FDA approved ... the counter drug over the counter in relatively low doses. The prototypical H sub 2 sub antagonist ... . History and development Cimetidine was the prototypical histamine H sub 2 sub receptor antagonist ... to develop a histamine receptor receptor antagonistantagonist that would suppress stomach acid ... antagonist traditional antihistamine s had no effect on acid production. From these facts the SK&F ..., a partial H sub 2 sub receptor antagonist. From this lead the receptor model was further refined and eventually led to the development of burimamide , a specific competitive antagonist at the H ... the first clinically successful H sub 2 sub antagonist. Ranitidine common brand name Zantac was developed ... sub 2 sub receptors are blocked. Like the H1 antagonist H sub 1 sub antihistamines , the H sub 2 sub antagonists are inverse agonist s rather than true receptor antagonist s. Citation needed date ... 7 1378 ref The H2 antagonist Ranitidine is prescribed by some urologists for patients with interstitial ... sv H2 antagonist th 2 tr H resept r antagonisti ... more details
A nicotinic antagonist is a type of anticholinergic that inhibits the action at nicotinic acetylcholine receptor s. These compounds are mainly used for peripheral muscle paralysis in surgery, but some centrally acting compounds such as bupropion , mecamylamine , and 18 methoxycoronaridine block nicotinic acetylcholine receptors in the brain and can be used for treating drug addiction . class wikitable Comparison Mechanism Antagonist Preferred receptor Clinical use rowspan 3 Ganglionic blocking agents Hexamethonium Ganglion type nicotinic receptor Ganglion type none ref name Rang149 cite book author Rang, H. P. title Pharmacology publisher Churchill Livingstone location Edinburgh year 2003 pages isbn 0 443 07145 4 oclc doi Page 149 ref Mecamylamine Ganglion type nicotinic receptor Ganglion type Trimethaphan Ganglion type nicotinic receptor Ganglion type Rarely used for blood pressure decrease during surgery ref name Rang149 rowspan 6 Nondepolarizing neuromuscular blocking agents Atracurium Muscle type nicotinic receptor Muscle type muscle relaxant in anaesthesia ref name Rang149 Doxacurium Muscle type nicotinic receptor Muscle type Mivacurium Muscle type nicotinic receptor Muscle type Pancuronium Muscle type nicotinic receptor Muscle type muscle relaxant in anaesthesia ref name Rang149 Tubocurarine Muscle type nicotinic receptor Muscle type Rarely used ref name Rang149 Vecuronium Muscle type nicotinic receptor Muscle type muscle relaxant in anaesthesia ref name Rang149 rowspan 1 Depolarizing neuromuscular blocking agents Suxamethonium chloride Succinylcholine Muscle type nicotinic receptor Muscle type rowspan 1 Centrally acting nicotinic antagonists 18 Methoxycoronaridine alpha3beta4 nicotinic 3 4 See also Nicotinic agonist References Reflist 2 External links MeshName Nicotinic antagonists Receptor agonists and antagonists Antiaddictives Antihypertensives and diuretics Muscle relaxants Cholinergics Category Nicotinic antagonists antihypertensive stub musculoskeletal ... more details
DISPLAYTITLE 5 HT sub 3 sub antagonist Drugclassbox Name 5 HT sub 3 sub receptor antagonist Image Ondansetron skeletal.svg Caption Skeletal formula of ondansetron , the prototypical 5 HT sub 3 sub antagonist ... antagonist s at the 5 HT3 receptor 5 HT sub 3 sub receptor , a subtype of serotonin 5 HT receptor ... HT3 receptor antagonist efficacy in refractory patients? journal Cancer Chemother Pharmacol volume ... 5 HT sub 3 sub receptor antagonist. ref name King 1993 Cite book last King first Frank D. last2 Jones ..., workers at Sandoz identified the potent, selective 5 HT sub 3 sub receptor antagonist ICS 205 930 ... in 1997. ref name Billio 2008 A new and improved 5 HT sub 3 sub receptor antagonist, named palonosetron ... antagonist antagonists were first introduced in the early 1990s, and they have become the most ... antagonist granisetron is located close to R92 and the aromatic rings lie close to W90 ... a 5 HT sub 3 sub receptor antagonist in the 5 HT sub 3 sub receptor binding pocket is with its ... antagonist ref name Thompson 2006 5 HT sub 3 sub receptor antagonists Binding affinity K sub d sub ... Fig 3. Ondansetron First generation 5 HT sub 3 sub receptor antagonist Image Palonosetron.svg thumb 200px Fig 4. Palonosetron Second generation 5 HT sub 3 sub receptor antagonist Chemical structures of the first generation 5 HT sub 3 sub receptor antagonist can be categorized to three main classes ... The first generation 5 HT sub 3 sub receptor antagonist ondansetron, dolasetron , granisetron ... and highly selective, second generation 5 HT sub 3 sub receptor antagonist. ref name Tian 2006 cite ... 200px Fig. 6 The main pharmacophoric elements of the known 5 HT sub 3 sub antagonist 5 HT sub 3 ... are valuable to investigate their structure and function. An antagonist like molecule with low ... of 5 HT sub 3 sub antagonists Despite that the 5 HT sub 3 sub receptor antagonist share their mechanism ... antagonist have similar activity. However patients who are resistant to one antagonist might benefit ... more details
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