:Kallidin
{{Chembox
| Watchedfields = changed
| verifiedrevid = 405924903
| ImageFile=Kallidin.svg
| ImageSize=200px
| ImageFile2=Kallidin 3D.png
| ImageSize2=200px
| IUPACName= L-Lysyl-L-arginyl-L-prolyl-L-prolyl-glycyl-L-phenylalanyl-L-seryl-L-prolyl-L-phenylalanyl-L-arginine
| OtherNames=
|Section1={{Chembox Identifiers
| IUPHAR_ligand = 650
| ChemSpiderID_Ref = {{chemspidercite|correct|chemspider}}
| ChemSpiderID = 4470640
| InChI = 1/C56H85N17O12/c57-24-8-7-18-36(58)46(76)67-37(19-9-25-63-55(59)60)51(81)73-29-13-23-44(73)53(83)72-28-11-21-42(72)49(79)65-32-45(75)66-39(30-34-14-3-1-4-15-34)47(77)70-41(33-74)52(82)71-27-12-22-43(71)50(80)69-40(31-35-16-5-2-6-17-35)48(78)68-38(54(84)85)20-10-26-64-56(61)62/h1-6,14-17,36-44,74H,7-13,18-33,57-58H2,(H,65,79)(H,66,75)(H,67,76)(H,68,78)(H,69,80)(H,70,77)(H,84,85)(H4,59,60,63)(H4,61,62,64)/t36-,37-,38-,39-,40-,41-,42-,43-,44-/m0/s1
| InChIKey = FYSKZKQBTVLYEQ-FSLKYBNLBR
| StdInChI_Ref = {{stdinchicite|correct|chemspider}}
| StdInChI = 1S/C56H85N17O12/c57-24-8-7-18-36(58)46(76)67-37(19-9-25-63-55(59)60)51(81)73-29-13-23-44(73)53(83)72-28-11-21-42(72)49(79)65-32-45(75)66-39(30-34-14-3-1-4-15-34)47(77)70-41(33-74)52(82)71-27-12-22-43(71)50(80)69-40(31-35-16-5-2-6-17-35)48(78)68-38(54(84)85)20-10-26-64-56(61)62/h1-6,14-17,36-44,74H,7-13,18-33,57-58H2,(H,65,79)(H,66,75)(H,67,76)(H,68,78)(H,69,80)(H,70,77)(H,84,85)(H4,59,60,63)(H4,61,62,64)/t36-,37-,38-,39-,40-,41-,42-,43-,44-/m0/s1
| StdInChIKey_Ref = {{stdinchicite|correct|chemspider}}
| StdInChIKey = FYSKZKQBTVLYEQ-FSLKYBNLSA-N
| CASNo_Ref = {{cascite|correct|??}}
| CASNo=342-10-9
| UNII_Ref = {{fdacite|correct|FDA}}
| UNII = 0T8T4A440G
| PubChem = 5311111
| SMILES = O=C(N[C@H](C(=O)N[C@H](C(=O)O)CCC/N=C(\N)N)Cc1ccccc1)[C@H]5N(C(=O)[C@@H](NC(=O)[C@@H](NC(=O)CNC(=O)[C@H]3N(C(=O)[C@H]2N(C(=O)[C@@H](NC(=O)[C@@H](N)CCCCN)CCC/N=C(\N)N)CCC2)CCC3)Cc4ccccc4)CO)CCC5
| MeSHName=Kallidin
}}
|Section2={{Chembox Properties
| C=56 | H=85 | N=17 | O=12
| Appearance=
| Density=
| MeltingPt=
| BoilingPt=
| Solubility=
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|Section3={{Chembox Hazards
| MainHazards=
| FlashPt=
| AutoignitionPt =
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Kallidin belongs to the family kinins, which are the peptide hormones.{{Cite journal |last=Hilgenfeldt |first=U. |last2=Linke |first2=R. |last3=Riester |first3=U. |last4=Konig |first4=W. |last5=Breipohl |first5=G. |date=June 1995 |title=Strategy of Measuring Bradykinin and Kallidin and Their Concentration in Plasma and Urine |url=https://linkinghub.elsevier.com/retrieve/pii/S0003269785713115 |journal=Analytical Biochemistry |language=en |volume=228 |issue=1 |pages=35–41 |doi=10.1006/abio.1995.1311|url-access=subscription }} Kallidin is a decapeptide whose sequence is H-Lys-Arg-Pro-Pro-Gly-Phe-Ser-Pro-Phe-Arg-OH. It can be converted to bradykinin by the aminopeptidase enzyme.{{fact|date=January 2025}}
Effects of Kinins
Kallidin is a bioactive kinin peptide formed in response to injury from kininogen precursors through the action of kallikreins.{{cite book |last1=Campbell |first1=Duncan John |title=Handbook of Biologically Active Peptides |date=2013 |isbn=978-0-12-385095-9 |pages=1386–1393 |chapter=Bradykinin Peptides |doi=10.1016/B978-0-12-385095-9.00188-3}} Like all kinins, kallidin, the deca-peptide, plays an important role in several body pathologies. Kinins can regulate the blood pressure by increasing the level of vasopressor substances.{{Cite journal |last=Guevara-Lora |first=Ibeth |last2=Labedz |first2=Anna |last3=Skrzeczynska-Moncznik |first3=Joanna |last4=and Kozik |first4=Andrzej |date=2011-08-01 |title=Bradykinin and des-Arg10-kallidin enhance the adhesion of polymorphonuclear leukocytes to extracellular matrix proteins and endothelial cells |url=https://www.tandfonline.com/doi/full/10.3109/15419061.2011.617854 |journal=Cell Communication & Adhesion |volume=18 |issue=4 |pages=67–71 |doi=10.3109/15419061.2011.617854 |issn=1541-9061 |pmid=21942713}} They can also bind to the B1 and B2 cell surface receptors, which are G-protein coupled receptors.{{Citation |last=Hall |first=Judith M. |title=2 - The Pharmacology and Immunopharmacology of Kinin Receptors |date=1997-01-01 |work=The Kinin System |pages=9–43 |editor-last=Farmer |editor-first=Stephen G. |url=https://linkinghub.elsevier.com/retrieve/pii/B9780122493409500048 |access-date=2025-05-03 |series=Handbook of Immunopharmacology |place=London |publisher=Academic Press |doi=10.1016/b978-012249340-9/50004-8 |isbn=978-0-12-249340-9 |last2=Morton |first2=Ian K. M.|url-access=subscription }} The mediation of the B1 receptors by des-Arg kinins as agonists can be expressed in several medical issues, such as cancer and trauma. By binding to the B2 receptors, kinins, endogenous agonists, can regulate the vasodilatation and bronchioconstriction.
Chemical Mechanisms
Since kinins are peptides, they can be cleaved by the peptidases. Peptidases such as the serine peptidases, carboxypeptidase N and carboxypeptidase M cleave kinins into des-Arg-bradykinin and Lys-des-Arg-bradykinin.{{Cite journal |last=Pelorosso |first=Facundo Germán |last2=Brodsky |first2=Paula Tamara |last3=Zold |first3=Camila Lidia |last4=Rothlin |first4=Rodolfo Pedro |date=June 2005 |title=Potentiation of des-Arg9-Kallidin-Induced Vasoconstrictor Responses by Metallopeptidase Inhibition in Isolated Human Umbilical Artery |url=https://linkinghub.elsevier.com/retrieve/pii/S0022356524320415 |journal=The Journal of Pharmacology and Experimental Therapeutics |language=en |volume=313 |issue=3 |pages=1355–1360 |doi=10.1124/jpet.105.083063|url-access=subscription }}{{cite book |doi=10.1007/978-3-540-38918-7_86 |chapter=Kinins |title=Encyclopedia of Molecular Pharmacology |date=2008 |last1=Herwald |first1=Heiko |last2=Müller-Esterl |first2=Werner |last3=Renné |first3=Thomas |pages=673–676 |isbn=978-3-540-38916-3 |chapter-url={{GBurl|iwwo5gx8aX8C|p=673}} }}
Clarification
Kallidin is identical to bradykinin with an additional lysine residue added at the N-terminal end and signals through the bradykinin receptor.{{fact|date=January 2025}}
Despite exhibiting similar functions and reactivities, kinins can be differentiated by combining an amino-terminal-directed radioimmunoassay with a carboxy-terminal-directed radioimmunoassay in combination with HPLC.