Relaxin - wikipedia Relaxin For the Miles Davis album, see Relaxin ' with the Miles Davis Quintet. Relaxin 1 Identifiers Symbol RLN1 Alt. symbols H1 Entrez 6013 HUGO 10026 OMIM 179730 RefSeq NM_006911 UniProt P04808 Other data Locus Chr. 9 qter - q12 Relaxin 2 Identifiers Symbol RLN2 Alt. symbols H2, RLXH2, bA12D24. 1.1, bA12D24. 1.2 Entrez 6019 HUGO 10027 OMIM 179740 PDB 6RLX RefSeq NM_134441 UniProt P04090 Other data Locus Chr. 9 qter - q12 Relaxin 3 Identifiers Symbol RLN3 Alt. symbols ZINS4, RXN3, H3 Entrez 117579 HUGO 17135 OMIM 606855 RefSeq NM_080864 UniProt Q8WXF3 Other data Locus Chr. 19 p13. 3 Relaxin is a protein hormone of about 6000 Da first described in 1926 by Frederick Hisaw. The relaxin - like peptide family belongs in the insulin superfamily and consists of 7 peptides of high structural but low sequence similarity ; relaxin - 1 ( RLN1 ), 2 ( RLN2 ) and 3 ( RLN3 ), and the insulin - like ( INSL ) peptides, INSL3, INSL4, INSL5 and INSL6. The functions of relaxin - 3, INSL4, INSL5, INSL6 remain uncharacterised. Contents 1 Synthesis 2 Structure 3 Function 3.1 In humans 3.2 In other animals 4 Receptors 5 Disorders 6 Pharmacological targets 7 Evolution 8 See also 9 References 10 External links Synthesis In the female, it is produced by the corpus luteum of the ovary, the breast and, during pregnancy, also by the placenta, chorion, and decidua. In the male, it is produced in the prostate and is present in human semen. Structure See also : Insulin / IGF / Relaxin family Structurally, relaxin is a heterodimer of two peptide chains of 24 and 29 amino acids linked by disulfide bridges, and it appears related to insulin. Relaxin is produced from its prohormone, `` prorelaxin '', by splitting off one additional peptide chain reaction. Function In humans In females, relaxin is produced mainly by the corpus luteum, in both pregnant and nonpregnant females ; it rises to a peak within approximately 14 days of ovulation, and then declines in the absence of pregnancy, resulting in menstruation ). During the first trimester of pregnancy, levels rise and additional relaxin is produced by the decidua. Relaxin 's peak is reached during the 14 weeks of the first trimester and at delivery. It is known to mediate the hemodynamic changes that occur during pregnancy, such as increased cardiac output, increased renal blood flow, and increased arterial compliance. It also relaxes other pelvic ligaments. It is believed to soften the pubic symphysis. In males, relaxin enhances motility of sperm in semen. In other animals In animals, relaxin widens the pubic bone and facilitates labor ; it also softens the cervix ( cervical ripening ), and relaxes the uterine musculature. Thus, for a long time, relaxin was looked at as a pregnancy hormone. However, its significance may reach much further. Relaxin affects collagen metabolism, inhibiting collagen synthesis and enhancing its breakdown by increasing matrix metalloproteinases. It also enhances angiogenesis and is a potent renal vasodilator. In the European Rabbit, ( Oryctolagus cuniculus ), relaxin is associated with squamous differentiation and is expressed in tracheobronchial epithelial cells as opposed to being involved with reproduction. Receptors Relaxin interacts with the relaxin receptor LGR7 ( RXFP1 ) and LGR8 ( RXFP2 ), which belong to the G protein - coupled receptor superfamily. They contain a heptahelical transmembrane domain and a large glycosylated ectodomain, distantly related to the receptors for the glycoproteohormones, such as the LH - receptor or FSH - receptor. Relaxin receptors have been found in the heart, smooth muscle, the connective tissue, and central and autonomous nervous system. Disorders Specific disorders related to relaxin have not been described, yet a link to scleroderma and fibromyalgia has been suggested. Pharmacological targets A recombinant form of human relaxin - 2 has been developed as investigational drug RLX030 ( serelaxin ). Evolution. Relaxin 1 and Relaxin 2 arose from the duplication of a proto - RLN gene between 44.2 and 29.6 million years ago in the last common ancestor of catarrhine primates. The duplication that led to RLN1 and RLN2 is thought to have been a result of positive selection and convergent evolution at the nucleotide level between the relaxin gene in New World monkeys and the RLN1 gene in apes. As a result, Old World monkeys, a group that includes the subfamilies colobines and cercopithecines, have lost the RLN1 paralog, but apes have retained both the RLN1 and the RLN2 genes ; Lawrence and Cords, 2012 ). See also Relaxin family peptide hormones Insulin / IGF / Relaxin ' family Relaxin ' / insulin - like family peptide receptor 1 References ^ Jump up to : Bani D ( January 1997 ). `` Relaxin : a pleiotropic hormone ''. General pharmacology. 28 ( 1 ) : 13 -- 22. doi : 10.1016 / s0306 - 3623 ( 96 ) 00171 - 1. PMID 9112071. Jump up ^ `` If a Gopher Can Do It... '' Time Magazine. 1944 - 04 - 10. Retrieved 2009 - 05 - 20. Jump up ^ Becker GJ, Hewitson TD ( March 2001 ). `` Relaxin and renal fibrosis ''. Kidney Int. 59 ( 3 ) : 1184 -- 5. doi : 10.1046 / j. 1523 - 1755.2001. 0590031184. x. PMID 11231378. Jump up ^ Wilkinson TN, Speed TP, Tregear GW, Bathgate RA ( February 2005 ). `` Evolution of the relaxin - like peptide family ''. BMC Evolutionary Biology. 5 : 14. doi : 10.1186 / 1471 - 2148 - 5 - 14. PMC 551602. PMID 15707501. Jump up ^ MacLennan AH ( 1991 ). `` The role of the hormone relaxin in human reproduction and pelvic girdle relaxation ''. Scandinavian journal of rheumatology. Supplement. 88 : 7 -- 15. PMID 2011710. Jump up ^ Conrad KP ( August 2011 ). `` Maternal vasodilation in pregnancy : the emerging role of relaxin ''. Am. J. Physiol. Regul. Integr. Comp. Physiol. 301 ( 2 ) : R267 -- 75. doi : 10.1152 / ajpregu. 00156.2011. PMC 3154715. PMID 21613576. Jump up ^ Weiss G ( February 1989 ). `` Relaxin in the male ''. Biol. Reprod. 40 ( 2 ) : 197 -- 200. doi : 10.1095 / biolreprod40. 2.197. PMID 2497805. Jump up ^ Mookerjee I, Solly NR, Royce SG, Tregear GW, Samuel CS, Tang ML ( 2006 ). `` Endogenous relaxin regulates collagen deposition in an animal model of allergic airway disease ''. Endocrinology. 147 ( 2 ) : 754 -- 61. doi : 10.1210 / en. 2005 - 1006. PMID 16254028. Jump up ^ Arroyo JI, Hoffmann FG, Opazo JC ( 2012 ). `` Gene duplication and positive selection explains unusual physiological roles of the relaxin gene in the European rabbit ''. Journal of Molecular Evolution. 74 ( 1 -- 2 ) : 52 -- 60. doi : 10.1007 / s00239 - 012 - 9487 - 2. PMID 22354201. Jump up ^ Hsu SY, Nakabayashi K, Nishi S, Kumagai J, Kudo M, Sherwood OD, Hsueh AJ ( 2002 ). `` Activation of orphan receptors by the hormone relaxin ''. Science. 295 ( 5555 ) : 674 -- 6. doi : 10.1126 / science. 1065654. PMID 11809971. Jump up ^ Van Der Westhuizen ET, Summers RJ, Halls ML, Bathgate RA, Sexton PM ( 2007 ). `` Relaxin receptors -- new drug targets for multiple disease states ''. Curr Drug Targets. 8 ( 1 ) : 91 -- 104. doi : 10.2174 / 138945007779315650. PMID 17266534. ^ Jump up to : Arroyo JI, Hoffmann FG, Opazo JC ( 2014 ). `` Evolution of the relaxin / insulin - like gene family in anthropoid primates ''. Genome Biology and Evolution. 6 ( 3 ) : 491 -- 9. doi : 10.1093 / gbe / evu023. PMC 3971578. PMID 24493383. External links Relaxin ' at the US National Library of Medicine Medical Subject Headings ( MeSH ) `` Relaxin ''. Human Protein Reference Database. Johns Hopkins University and the Institute of Bioinformatics. Retrieved 2009 - 05 - 20. Hormones Endocrine glands Hypothalamic - pituitary Hypothalamus GnRH TRH Dopamine CRH GHRH Somatostatin ( GHIH ) MCH Posterior pituitary Oxytocin Vasopressin Anterior pituitary FSH LH TSH Prolactin POMC CLIP ACTH MSH Endorphins Lipotropin GH Adrenal axis Adrenal cortex aldosterone cortisol cortisone DHEA DHEA - S androstenedione Adrenal medulla epinephrine norepinephrine Thyroid Thyroid hormones Calcitonin Thyroid axis Parathyroid PTH Gonadal axis Testis testosterone AMH inhibin Ovary estradiol progesterone activin and inhibin relaxin Placenta hCG HPL estrogen progesterone Pancreas glucagon insulin amylin somatostatin pancreatic polypeptide Pineal gland melatonin N, N - dimethyltryptamine 5 - methoxy - N, N - dimethyltryptamine Other Thymus Thymosins Thymosin α1 Beta thymosins Thymopoietin Thymulin Digestive system Stomach gastrin ghrelin Duodenum CCK Incretins GIP GLP - 1 secretin motilin VIP Ileum enteroglucagon peptide YY Liver / other Insulin - like growth factor IGF - 1 IGF - 2 Adipose tissue leptin adiponectin resistin Skeleton Osteocalcin Kidney renin EPO calcitriol prostaglandin Heart Natriuretic peptide ANP BNP Signaling peptide / protein receptor modulators Adiponectin AdipoR Agonists : Peptide : Adiponectin ADP - 355 ADP - 399 ; Non-peptide : AdipoRon ( -- ) - Arctigenin Arctiin Gramine Matairesinol Antagonists : Peptide : ADP - 400 AdipoR Agonists : Peptide : Adiponectin ADP - 355 ADP - 399 ; Non-peptide : AdipoRon Deoxyschizandrin Parthenolide Syringing Taxifoliol Antagonists : Peptide : ADP - 400 Angiotensin See here instead. Bradykinin Agonists : Bradykinin Kallidin Antagonists : FR - 173657 Icatibant LF22 - 0542 CGRP Agonists : Amylin CGRP Pramlintide Antagonists : Atogepant BI 44370 TA CGRP ( 8 - 37 ) MK - 3207 Olcegepant Rimegepant SB - 268262 Telcagepant Ubrogepant Antibodies : Eptinezumab Erenumab Fremanezumab Galcanezumab Cholecystokinin CCK Agonists : Cholecystokinin Antagonists : Amiglumide Asperlicin Devazepide Dexloxiglumide Lintitript Lorglumide Loxiglumide Pranazepide Proglumide Tarazepide Tomoglumide CCK Agonists : Cholecystokinin CCK - 4 Gastrin Pentagastrin ( CCK - 5 ) Antagonists : Ceclazepide CI - 988 ( PD - 134308 ) Itriglumide L - 365,360 Netazepide Proglumide Spiroglumide Unsorted Antagonists : Nastorazepide CRH CRF Agonists : Cortagine Corticorelin Corticotropin releasing hormone Sauvagine Stressin I Urocortin Antagonists : Antalarmin Astressin - B CP - 154,526 Emicerfont Hypericin LWH - 234 NBI - 27914 Pexacerfont R - 121919 TS - 041 Verucerfont CRF Agonists : Corticorelin Corticotropin releasing hormone Sauvagine Urocortin Antagonists : Astressin - B Cytokine See here instead. Endothelin Agonists : Endothelin 1 Endothelin 2 Endothelin 3 IRL - 1620 Antagonists : A-192621 ACT - 132577 Ambrisentan Aprocitentan Atrasentan Avosentan Bosentan BQ - 123 BQ - 788 Clazosentan Darusentan Edonentan Enrasentan Fandosentan Feloprentan Macitentan Nebentan Sitaxentan Sparsentan Tezosentan Zibotentan Galanin GAL Agonists : Galanin Galanin ( 1 - 15 ) Galanin - like peptide Galmic Galnon NAX 810 - 2 Antagonists : C7 Dithiepine - 1, 1, 4, 4 - tetroxide Galantide ( M15 ) M32 M35 M40 SCH - 202596 GAL Agonists : Galanin Galanin ( 1 - 15 ) Galanin ( 2 - 11 ) Galanin - like peptide Galmic Galnon J18 NAX 810 - 2 Antagonists : C7 Galantide ( M15 ) M32 M35 M40 M871 GAL Agonists : Galanin Galanin ( 1 - 15 ) Galmic Galnon Antagonists : C7 Galantide ( M15 ) GalR3ant HT - 2157 M32 M35 M40 SNAP - 37889 SNAP - 398299 Ghrelin / GHS See here instead. GH See here instead. GHRH See here instead. GLP GLP - 1 Agonists : Albiglutide Beinaglutide Dulaglutide Efpeglenatide Exenatide GLP - 1 Langlenatide Liraglutide Lixisenatide Oxyntomodulin Semaglutide Taspoglutide GLP - 2 Agonists : Apraglutide Elsiglutide Glepaglutide GLP - 2 Teduglutide Others Propeptides : Preproglucagon Proglucagon Glucagon Agonists : Dasiglucagon Glucagon Oxyntomodulin Antagonists : Adomeglivant L - 168,049 LGD - 6972 Propeptides : Preproglucagon Proglucagon GnRH See here instead. Gonadotropin See here instead. Growth factor See here instead. Insulin Agonists : Chaetochromin ( 4548 - G05 ) Insulin - like growth factor 1 Insulin - like growth factor 2 Insulin Insulin aspart Insulin degludec Insulin detemir Insulin glargine Insulin glulisine Insulin lispro Mecasermin Mecasermin rinfabate Antagonists : BMS - 754807 S661 S961 Kinase inhibitors : Linsitinib Antibodies : Xentuzumab ( against IGF - 1 and IGF - 2 ) Kisspeptin Agonists : Kisspeptin Kisspeptin - 10 Antagonists : Kisspeptin - 234 Leptin Agonists : Leptin Metreleptin MCH MCH Agonists : Melanin concentrating hormone Antagonists : ATC - 0065 ATC - 0175 GW - 803430 NGD - 4715 SNAP - 7941 SNAP - 94847 MCH Agonists : Melanin concentrating hormone Melanocortin See here instead. Neuropeptide FF Agonists : Neuropeptide AF Neuropeptide FF Neuropeptide SF ( RFRP - 1 ) Neuropeptide VF ( RFRP - 3 ) Antagonists : BIBP - 3226 RF9 Neuropeptide S Agonists : Neuropeptide S Antagonists : ML - 154 SHA - 68 Neuropeptide Y Y Agonists : Neuropeptide Y Peptide YY Antagonists : BIBO - 3304 BIBP - 3226 BVD - 10 GR - 231118 PD - 160170 Y Agonists : 2 - Thiouridine 5 ' - triphosphate Neuropeptide Y Neuropeptide Y ( 13 - 36 ) Peptide YY Peptide YY ( 3 - 36 ) Antagonists : BIIE - 0246 JNJ - 5207787 SF - 11 Y Agonists : GR - 231118 Neuropeptide Y Pancreatic polypeptide Peptide YY Antagonists : UR - AK49 Y Agonists : BWX - 46 Neuropeptide Y Peptide YY Antagonists : CGP - 71683 FMS - 586 L - 152,804 Lu AA - 33810 MK - 0557 NTNCB Velneperit ( S - 2367 ) Neurotensin NTS Agonists : Neurotensin Neuromedin N Antagonists : Meclinertant SR - 142948 NTS Agonists : Neurotensin Antagonists : Levocabastine SR - 142948 Opioid See here instead. Orexin OX Agonists : Orexin ( A, B) Antagonists : ACT - 335827 ACT - 462206 Almorexant Filorexant Lemborexant SB - 334867 SB - 408124 SB - 649868 Suvorexant TCS - 1102 OX Agonists : Orexin ( A, B) SB - 668875 Antagonists : ACT - 335827 ACT - 462206 Almorexant EMPA Filorexant JNJ - 10397049 Lemborexant MK - 1064 SB - 649868 Seltorexant Suvorexant TCS - 1102 TCS - OX2 - 29 Oxytocin See here instead. Prolactin Agonists : Growth hormone Human placental lactogen Placental growth hormone ( growth hormone variant ) Prolactin S179D - hPRL Somatotropin Antagonists : Δ1 -- 9 - G129R - hPRL Δ1 -- 14 - G129R - hPRL G120K - hGH G129R - hPRL Prolactin modulators : Prolactin inhibitors : D receptor agonists ( e.g., bromocriptine, cabergoline ) ; Prolactin releasers : D receptor antagonists ( e.g., domperidone, metoclopramide, risperidone ) Estrogens ( e.g., estradiol ) Progestogens ( e.g., progesterone ) PTH Agonists : Abaloparatide Parathyroid hormone Parathyroid hormone - related protein ( PTHrP ) Semparatide Teriparatide Relaxin Agonists : Insulin - like factor 3 Relaxin ( 1, 2, 3 ) Serelaxin Somatostatin See here instead. Tachykinin See here instead. TRH Agonists : Azetirelin Fertirelin Montirelin Orotirelin Posatirelin Protirelin Rovatirelin Taltirelin TRH ( TRF ) TSH Agonists : Thyrotropin alfa TSH ( thyrotropin ) Vasopressin See here instead. VIP / PACAP VIPR Agonists : Peptide : Bay 55 - 9837 LBT - 3393 PACAP VIP VIPR Agonists : Peptide : LBT - 3627 PACAP VIP PAC Agonists : PACAP PACAP ( 1 - 27 ) PACAP ( 1 - 38 ) Antagonists : PACAP ( 6 - 38 ) Unsorted PHI PHM PHV Others Endogenous : Adrenomedullin Apelin Asprosin Bombesin Calcitonin Carnosine CART CLIP DSIP Enteroglucagon Formyl peptide GALP GIP GRP Integrin ligands ( collagens, fibrinogen, fibronectin, laminins, ICAM - 1, ICAM - 2, osteopontin, VCAM - 1, vitronectin ) Kininogens Motilin Natriuretic peptides ( ANP, BNP, CNP, urodilatin ) Nesfatin - 1 Neuromedin B Neuromedin N Neuromedin S Neuromedin U Obestatin Osteocalcin Resistin Secretin Thymopoietin Thymosins Thymulin Urotensin - II VGF Exogenous : Lifitegrast ( LFA - 1 antagonist ) See also Receptor / signaling modulators NDL : 00575760 Retrieved from `` https://en.wikipedia.org/w/index.php?title=Relaxin&oldid=836353911 '' Categories : Genes on human chromosome 9 Genes on human chromosome 19 Peptide hormones Hormones of the ovary Hormones of the placenta Hormones of the pregnant female Human female endocrine system Hidden categories : All articles with dead external links Articles with dead external links from April 2018 Articles with permanently dead external links Protein pages needing a picture All articles with unsourced statements Articles with unsourced statements from August 2013 Talk Contents About Wikipedia Dansk Deutsch ދިވެހިބަސް Español Français Galego Italiano 日本 語 Polski Português Română Русский Simple English Српски / srpski Srpskohrvatski / српскохрватски Svenska 8 more Edit links This page was last edited on 14 April 2018, at 07 : 54. 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Question: when does relaxin start being produced during pregnancy
Answer: During the first trimester of pregnancy