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28-546: MSH may refer to: Biology and medicine [ edit ] Melanocyte-stimulating hormone , a hormone produced in the pituitary gland, and related to skin pigmentation DNA mismatch repair genes: MSH2 MSH3 MSH4 MSH5 MSH6 Multiple system atrophy Mycothiol , an unusual thiol that is found in Actinobacteria Computing [ edit ] Microsoft Surface Hub Monad Shell (msh),

56-534: A family of peptide hormones and neuropeptides consisting of α-melanocyte-stimulating hormone (α-MSH), β-melanocyte-stimulating hormone (β-MSH), and γ-melanocyte-stimulating hormone (γ-MSH) that are produced by cells in the pars intermedia of the anterior lobe of the pituitary gland . Synthetic analogues of α-MSH, such as afamelanotide (melanotan I; Scenesse), melanotan II , and bremelanotide (PT-141), have been developed and researched. The various forms of MSH are generated from different cleavages of

84-590: A former name for the Microsoft Windows PowerShell Places [ edit ] Maharashtra state highway , India Markham Stouffville Hospital , Ontario, Canada RAFO Masirah airport, Oman (IATA: MSH) Mississippi State Hospital , US Mossley Hill railway station , England Mount St. Helens , volcano in Washington, US Mount Sinai Hospital, Toronto , Canada Other uses [ edit ] Maison des Sciences de L'Homme ,

112-474: A regulative force must exist within living bodies. Berzelius also contended that compounds could be distinguished by whether they required any organisms in their synthesis (organic compounds) or whether they did not ( inorganic compounds ). Vitalism taught that formation of these "organic" compounds were fundamentally different from the "inorganic" compounds that could be obtained from the elements by chemical manipulations in laboratories. Vitalism survived for

140-503: A research foundation in Paris, France Management Sciences for Health , a non-profit Marvel Super Heroes (disambiguation) , in entertainment Masikoro language , spoken in Madagascar (ISO 639: msh) Topics referred to by the same term [REDACTED] This disambiguation page lists articles associated with the title MSH . If an internal link led you here, you may wish to change

168-452: A short period after the formulation of modern ideas about the atomic theory and chemical elements . It first came under question in 1824, when Friedrich Wöhler synthesized oxalic acid , a compound known to occur only in living organisms, from cyanogen . A further experiment was Wöhler's 1828 synthesis of urea from the inorganic salts potassium cyanate and ammonium sulfate . Urea had long been considered an "organic" compound, as it

196-404: A single element and so not generally considered chemical compounds . The word "organic" in this context does not mean "natural". Vitalism was a widespread conception that substances found in organic nature are formed from the chemical elements by the action of a "vital force" or "life-force" ( vis vitalis ) that only living organisms possess. In the 1810s, Jöns Jacob Berzelius argued that

224-634: A small percentage of Earth's crust , they are of central importance because all known life is based on organic compounds. Living things incorporate inorganic carbon compounds into organic compounds through a network of processes ( the carbon cycle ) that begins with the conversion of carbon dioxide and a hydrogen source like water into simple sugars and other organic molecules by autotrophic organisms using light ( photosynthesis ) or other sources of energy. Most synthetically-produced organic compounds are ultimately derived from petrochemicals consisting mainly of hydrocarbons , which are themselves formed from

252-421: A transition metal and to oxygen, and are often prepared directly from metal and carbon monoxide . Nickel tetracarbonyl is typically classified as an organometallic compound as it satisfies the broad definition that organometallic chemistry covers all compounds that contain at least one carbon to metal covalent bond; it is unknown whether organometallic compounds form a subset of organic compounds. For example,

280-1692: A variety of ways. One major distinction is between natural and synthetic compounds. Organic compounds can also be classified or subdivided by the presence of heteroatoms , e.g., organometallic compounds , which feature bonds between carbon and a metal , and organophosphorus compounds , which feature bonds between carbon and a phosphorus . Another distinction, based on the size of organic compounds, distinguishes between small molecules and polymers . Natural compounds refer to those that are produced by plants or animals. Many of these are still extracted from natural sources because they would be more expensive to produce artificially. Examples include most sugars , some alkaloids and terpenoids , certain nutrients such as vitamin B 12 , and, in general, those natural products with large or stereoisometrically complicated molecules present in reasonable concentrations in living organisms. Further compounds of prime importance in biochemistry are antigens , carbohydrates , enzymes , hormones , lipids and fatty acids , neurotransmitters , nucleic acids , proteins , peptides and amino acids , lectins , vitamins , and fats and oils . Compounds that are prepared by reaction of other compounds are known as " synthetic ". They may be either compounds that are already found in plants/animals or those artificial compounds that do not occur naturally . Most polymers (a category that includes all plastics and rubbers ) are organic synthetic or semi-synthetic compounds. Many organic compounds—two examples are ethanol and insulin —are manufactured industrially using organisms such as bacteria and yeast. Typically,

308-972: Is any compound that contains a significant amount of carbon—even though many of the organic compounds known today have no connection to any substance found in living organisms. The term carbogenic has been proposed by E. J. Corey as a modern alternative to organic , but this neologism remains relatively obscure. The organic compound L -isoleucine molecule presents some features typical of organic compounds: carbon–carbon bonds , carbon–hydrogen bonds , as well as covalent bonds from carbon to oxygen and to nitrogen. As described in detail below, any definition of organic compound that uses simple, broadly-applicable criteria turns out to be unsatisfactory, to varying degrees. The modern, commonly accepted definition of organic compound essentially amounts to any carbon-containing compound, excluding several classes of substances traditionally considered "inorganic". The list of substances so excluded varies from author to author. Still, it

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336-710: Is generally agreed upon that there are (at least) a few carbon-containing compounds that should not be considered organic. For instance, almost all authorities would require the exclusion of alloys that contain carbon, including steel (which contains cementite , Fe 3 C ), as well as other metal and semimetal carbides (including "ionic" carbides, e.g, Al 4 C 3 and CaC 2 and "covalent" carbides, e.g. B 4 C and SiC , and graphite intercalation compounds, e.g. KC 8 ). Other compounds and materials that are considered 'inorganic' by most authorities include: metal carbonates , simple oxides of carbon ( CO , CO 2 , and arguably, C 3 O 2 ),

364-485: Is increased when the animal is in a dark location. This causes pigment to be dispersed in pigment cells in the toad's skin, making it become darker, and harder for predators to spot. The pigment cells are called melanophores and therefore, in amphibians, the hormone is often called melanophore-stimulating hormone. An increase in MSH will cause darker skin in humans too. Pigmentation increases in humans during pregnancy ; though

392-479: Is on a carbon atom. For historical reasons discussed below, a few types of carbon-containing compounds, such as carbides , carbonates (excluding carbonate esters ), simple oxides of carbon (for example, CO and CO 2 ) and cyanides are generally considered inorganic compounds . Different forms ( allotropes ) of pure carbon, such as diamond , graphite , fullerenes and carbon nanotubes are also excluded because they are simple substances composed of

420-781: The allotropes of carbon, cyanide derivatives not containing an organic residue (e.g., KCN , (CN) 2 , BrCN , cyanate anion OCN , etc.), and heavier analogs thereof (e.g., cyaphide anion CP , CSe 2 , COS ; although carbon disulfide CS 2 is often classed as an organic solvent). Halides of carbon without hydrogen (e.g., CF 4 and CClF 3 ), phosgene ( COCl 2 ), carboranes , metal carbonyls (e.g., nickel tetracarbonyl ), mellitic anhydride ( C 12 O 9 ), and other exotic oxocarbons are also considered inorganic by some authorities. Nickel tetracarbonyl ( Ni(CO) 4 ) and other metal carbonyls are often volatile liquids, like many organic compounds, yet they contain only carbon bonded to

448-419: The proopiomelanocortin protein, which also yields other important neuropeptides like adrenocorticotropic hormone . Melanocytes in skin make and secrete MSH in response to ultraviolet light, where it increases synthesis of melanin . Some neurons in arcuate nucleus of the hypothalamus make and secrete α-MSH in response to leptin ; α-MSH is also made and secreted in the anterior lobe of

476-498: The better known are afamelanotide (melanotan I) in testing by Clinuvel Pharmaceuticals and bremelanotide by Palatin Technologies . Others include modimelanotide and setmelanotide . Organic compound#Synthetic compounds Due to carbon's ability to catenate (form chains with other carbon atoms ), millions of organic compounds are known. The study of the properties, reactions, and syntheses of organic compounds comprise

504-451: The blood. The different forms of MSH belong to a group called the melanocortins . This group includes ACTH, α-MSH, β-MSH, and γ-MSH; these peptides are all cleavage products of a large precursor peptide called proopiomelanocortin (POMC). α-MSH is the most important melanocortin for pigmentation. The different forms of MSH have the following amino acid sequences : Synthetic analogues of α-MSH have been developed for human use. Two of

532-576: The discipline known as organic chemistry . For historical reasons, a few classes of carbon-containing compounds (e.g., carbonate salts and cyanide salts ), along with a few other exceptions (e.g., carbon dioxide , and even hydrogen cyanide despite the fact it contains a carbon-hydrogen bond), are generally considered inorganic . Other than those just named, little consensus exists among chemists on precisely which carbon-containing compounds are excluded, making any rigorous definition of an organic compound elusive. Although organic compounds make up only

560-938: The evidence of covalent Fe-C bonding in cementite , a major component of steel, places it within this broad definition of organometallic, yet steel and other carbon-containing alloys are seldom regarded as organic compounds. Thus, it is unclear whether the definition of organometallic should be narrowed, whether these considerations imply that organometallic compounds are not necessarily organic, or both. Metal complexes with organic ligands but no carbon-metal bonds (e.g., (CH 3 CO 2 ) 2 Cu ) are not considered organometallic; instead, they are called metal-organic compounds (and might be considered organic). The relatively narrow definition of organic compounds as those containing C-H bonds excludes compounds that are (historically and practically) considered organic. Neither urea CO(NH 2 ) 2 nor oxalic acid (COOH) 2 are organic by this definition, yet they were two key compounds in

588-447: The exact endocrine cause is not known, α- and β-melanocyte-stimulating hormone are thought to be involved. Cushing's disease due to excess adrenocorticotropic hormone (ACTH) may also result in hyperpigmentation, such as acanthosis nigricans in the axilla . Most people with primary Addison's disease have darkening ( hyperpigmentation ) of the skin, including areas not exposed to the sun; characteristic sites are skin creases (e.g. of

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616-477: The hands), nipple, and the inside of the cheek (buccal mucosa), new scars become hyperpigmented, whereas older ones do not darken. This occurs because MSH and ACTH share the same precursor molecule, proopiomelanocortin (POMC). Different levels of MSH are not the major cause of variation in skin colour . However, in many red-headed people, and other people who do not tan well, there are variations in their hormone receptors , causing them to not respond to MSH in

644-404: The high pressure and temperature degradation of organic matter underground over geological timescales. This ultimate derivation notwithstanding, organic compounds are no longer defined as compounds originating in living things, as they were historically. In chemical nomenclature, an organyl group , frequently represented by the letter R, refers to any monovalent substituent whose open valence

672-495: The link to point directly to the intended article. Retrieved from " https://en.wikipedia.org/w/index.php?title=MSH&oldid=1173893181 " Category : Disambiguation pages Hidden categories: Short description is different from Wikidata All article disambiguation pages All disambiguation pages Melanocyte-stimulating hormone The melanocyte-stimulating hormones , known collectively as MSH , also known as melanotropins or intermedins , are

700-601: The mineral mellite ( Al 2 C 6 (COO) 6 ·16H 2 O ). A slightly broader definition of the organic compound includes all compounds bearing C-H or C-C bonds. This would still exclude urea. Moreover, this definition still leads to somewhat arbitrary divisions in sets of carbon-halogen compounds. For example, CF 4 and CCl 4 would be considered by this rule to be "inorganic", whereas CHF 3 , CHCl 3 , and C 2 Cl 6 would be organic, though these compounds share many physical and chemical properties. Organic compounds may be classified in

728-426: The pituitary gland . Acting through melanocortin 1 receptor , α-MSH stimulates the production and release of melanin (a process referred to as melanogenesis ) by melanocytes in skin and hair . Acting in the hypothalamus, α-MSH suppresses appetite. α-MSH secreted in the hypothalamus also contributes to sexual arousal . In some animals (such as the claw-toed frog Xenopus laevis ) production of MSH

756-577: The vitalism debate. However, the IUPAC Blue Book on organic nomenclature specifically mentions urea and oxalic acid as organic compounds. Other compounds lacking C-H bonds but traditionally considered organic include benzenehexol , mesoxalic acid , and carbon tetrachloride . Mellitic acid , which contains no C-H bonds, is considered a possible organic compound in Martian soil. Terrestrially, it, and its anhydride, mellitic anhydride , are associated with

784-445: Was known to occur only in the urine of living organisms. Wöhler's experiments were followed by many others, in which increasingly complex "organic" substances were produced from "inorganic" ones without the involvement of any living organism, thus disproving vitalism. Although vitalism has been discredited, scientific nomenclature retains the distinction between organic and inorganic compounds. The modern meaning of organic compound

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