Editing Histamine (section)

{{Short description|Organic compound involved in immune responses}}
{{About||the use as an immunostimulant drug|Histamine dihydrochloride}}
{{chembox
| Verifiedimages = changed
| Watchedfields = changed
| verifiedrevid = 443858090
| ImageFile_Ref = {{chemboximage|correct|??}}
| ImageFile = Histamine.svg
| ImageSize =
| ImageClass = skin-invert
| ImageFile2 = Histamine 3D ball.png
| ImageSize2 =
| IUPACName = 2-(1''H''-Imidazol-4-yl)ethanamine
| OtherNames =

|Section1 = {{Chembox Identifiers
| UNII_Ref = {{fdacite|correct|FDA}}
| UNII = 820484N8I3
| KEGG_Ref = {{keggcite|correct|kegg}}
| KEGG = D08040
| InChI = 1/C5H9N3/c6-2-1-5-3-7-4-8-5/h3-4H,1-2,6H2,(H,7,8)
| InChIKey = NTYJJOPFIAHURM-UHFFFAOYAP
| ChEMBL_Ref = {{ebicite|correct|EBI}}
| ChEMBL = 90
| StdInChI_Ref = {{stdinchicite|correct|chemspider}}
| StdInChI = 1S/C5H9N3/c6-2-1-5-3-7-4-8-5/h3-4H,1-2,6H2,(H,7,8)
| StdInChIKey_Ref = {{stdinchicite|correct|chemspider}}
| StdInChIKey = NTYJJOPFIAHURM-UHFFFAOYSA-N
| CASNo_Ref = {{cascite|correct|CAS}}
| CASNo = 51-45-6
| PubChem = 774
| IUPHAR_ligand = 1204
| ChemSpiderID_Ref = {{chemspidercite|correct|chemspider}}
| ChemSpiderID = 753
| ChEBI_Ref = {{ebicite|correct|EBI}}
| ChEBI = 18295
| SMILES = NCCc1c[nH]cn1
| MeSHName=Histamine
| DrugBank = DB05381
  }}

|Section2 = {{Chembox Properties
| C=5 | H=9 | N=3
| Appearance=
| Density=
| MeltingPtC= 83.5
| BoilingPtC= 209.5
| LogP = −0.7<ref name=Vuckovic>{{cite journal | vauthors = Vuckovic D, Pawliszyn J | title = Systematic evaluation of solid-phase microextraction coatings for untargeted metabolomic profiling of biological fluids by liquid chromatography-mass spectrometry | journal = Analytical Chemistry | volume = 83 | issue = 6 | pages = 1944–54 | date = March 2011 | pmid = 21332182 | doi = 10.1021/ac102614v }}</ref>
| pKa = [[Imidazole]]: 6.04 <br> Terminal NH<sub>2</sub>: 9.75<ref name=Vuckovic />
| Solubility = Easily soluble in cold water, hot water<ref name="sciencelab.com">{{cite tech report |title=Histamine Material Safety Data Sheet |institution=sciencelab.com |date=2013-05-21 |url=http://www.sciencelab.com/msds.php?msdsId=9924264 |url-status=live |archive-url=https://web.archive.org/web/20120324194707/http://www.sciencelab.com/msds.php?msdsId=9924264 |archive-date=2012-03-24 }}</ref>
| SolubleOther = Easily soluble in methanol. Very slightly soluble in diethyl ether.<ref name="sciencelab.com"/> Easily soluble in ethanol.
| Solvent = other solvents
  }}
|Section6 = {{Chembox Pharmacology
| ATCCode_prefix = L03
| ATCCode_suffix = AX14
| ATC_Supplemental = {{ATC|V04|CG03}} (phosphate)
}}
|Section7 = {{Chembox Hazards
| MainHazards =
| FlashPt =
| AutoignitionPt =
  }}
}}

'''Histamine''' is an organic [[nitrogen]]ous compound involved in local [[immune system|immune responses communication]], as well as regulating [[Physiology|physiological functions]] in the [[Gastrointestinal tract|gut]] and acting as a [[neurotransmitter]] for the [[brain]], [[spinal cord]], and [[uterus]].<ref>{{cite book | vauthors = Marieb E |title=Human anatomy & physiology |url=https://archive.org/details/humananatomyphys00mari |url-access=registration |publisher=Benjamin Cummings |location=San Francisco |year=2001 |pages=[https://archive.org/details/humananatomyphys00mari/page/414 414] |isbn=0-8053-4989-8 }}</ref><ref>{{cite journal | vauthors = Nieto-Alamilla G, Márquez-Gómez R, García-Gálvez AM, Morales-Figueroa GE, Arias-Montaño JA | title = The Histamine H3 Receptor: Structure, Pharmacology, and Function | journal = Molecular Pharmacology | volume = 90 | issue = 5 | pages = 649–673 | date = November 2016 | pmid = 27563055 | doi = 10.1124/mol.116.104752 | doi-access = free }}</ref> Discovered in 1910, histamine has been considered a local [[hormone]] ([[Autacoid|autocoid]]) because it is produced without involvement of the classic [[endocrine]] [[gland]]s; however, in recent years, histamine has been recognized as a central [[neurotransmitter]].<ref name="pmid27028114">{{cite journal | vauthors = Keppel Hesselink JM | title = The terms 'autacoid', 'hormone' and 'chalone' and how they have shifted with time | journal = Autonomic & Autacoid Pharmacology | volume = 35 | issue = 4 | pages = 51–8 | date = December 2015 | pmid = 27028114 | doi = 10.1111/aap.12037 | url = }}</ref> Histamine is involved in the [[inflammatory response]] and has a central role as a mediator of [[itching]].<ref name=andersen>{{cite journal | vauthors = Andersen HH, Elberling J, Arendt-Nielsen L | title = Human surrogate models of histaminergic and non-histaminergic itch | journal = Acta Dermato-Venereologica | volume = 95 | issue = 7 | pages = 771–7 | date = September 2015 | pmid = 26015312 | doi = 10.2340/00015555-2146 | doi-access = free | url = https://vbn.aau.dk/files/219083590/4442_9.pdf | access-date = 2024-02-20 | archive-date = 2019-03-30 | archive-url = https://web.archive.org/web/20190330070753/http://vbn.aau.dk/files/219083590/4442_9.pdf | url-status = live }}</ref> As part of an immune response to foreign [[pathogens]], histamine is produced by [[basophil]]s and by [[mast cell]]s found in nearby [[connective tissue]]s.  Histamine increases the [[Semipermeable membrane|permeability]] of the [[capillaries]] to [[white blood cells]] and some [[protein]]s, to allow them to engage [[pathogen]]s in the [[Infection|infected]] tissues.<ref>{{cite book |title=Nelson Biology 12 |url=https://archive.org/details/nelsonbiology12gius |url-access=limited | vauthors = Di Giuseppe M, Fraser D |year=2003 |publisher=Thomson Canada |location=Toronto |isbn=0-17-625987-2 |page=[https://archive.org/details/nelsonbiology12gius/page/n373 473] }}</ref> It consists of an [[imidazole]] ring attached to an [[ethylamine]] chain; under [[physiological condition]]s, the [[amino group]] of the side-chain is [[protonated]].