Kitsize12x8MethodELISAIncubationtime1x1h,1x10minStandardrange25-2500pg/mLSpecimen/Volumes50µLserum/withoutextractionSubstrate/isotopeTMB450nmRegulatoryStatus:EU:CE,CDN:IVDDetailsfor: 5alpha-DihydrotestosteroneELISAMarkerforandrogenicactivityIBLInternationalofferstheonlyworldwidecommerciallyavailabledirectELISAformeasuring5α–Dihydrotestosterone(DHT)inserum.Resultscanbeobtainedwithin1.5hours.MeasuringDHTlevelsfindsitsapplicationingynecology,pediatrics,endocrinologyandbiochemistry.AndrogenicSteroidDHTisessentialforthedevelopmentofthemalesexcharacteristicsbeforebirth,particularlytheformationoftheexternalgenitalia.Intheadult,DHTisneededtodevelopandmaintainmalegendercharacteristics,suchasfacialhair,deepvoice,andmusclegrowth.Inwomen,DHTmayinducetheonsetofpubertyandcausesthebodyandpubichairgrowth.Inmales,about70%ofDHTisderivedfromconversionoftestosteroneby5α–Reductaseintheprostate,testes,hairfollicles,andadrenalglands.InfemalesmostoftheDHTisderivedfromandrostenedione.DHThasapproximately3timesgreateraffinityforandrogenreceptorsthantestosteroneandhas15-30timesgreateraffinitythanadrenalandrogens.DHTPathologies5α–Reductasedeficiencycanresultinpseudo–hermaphroditism.DHTistheprimarycontributingfactorinmalepatternbaldnessandmaycontributetothedevelopmentofbenignprostatichyperplasia,aswellasprostatecancer.WomenwithincreasedlevelsofDHTmaysufferfromfemaleandrogenismbydevelopingandrogynoussecondarysexcharacteristics.ActionofDHTandtestosteroneontheandrogenreceptorsandinductionofBIOLOGicaleffects.SynonymsAndrostanolone(5α–Androstan–17β–ol–3–one)17β–hydroxy–5α–Androstan–3–oneClinicalapplicationsFemaleAndrogenismDHTisthebestmarkerforfemaleandrogenism,complementarymarkertotestosterone.IncreasedDHTlevelsarefoundinabout40%ofpatientswithidiopathichirsutismand35%ofpatientswithpolycysticovariansyndrome.WomenwithtoomuchDHTmaydevelopincreasedbody,facialandpubichairgrowth,amenorrhoeaandincreasedacne.AbnormalchangestothegenitaliamayalsooccurinwomenwithtoomuchDHT.MalePatternBaldness(MPB)DHTistheprimarycontributingfactorinmalepatternbaldness(MPB)orAndrogenicalopecia.MenwithMPBtypicallyhavehigherlevelsofDHT,lowerlevelsoftotaltestosteroneandhigherlevelsoffreetestosterone.ThetargetinterventiononthepatientsthatsufferfrombaldnessistopreventDHTfromactingonscalpandrogenreceptors.BenignProstaticHyperplasia(BPH)DHTplaysaroleinthedevelopmentandexacerbationofbenignprostatichyperplasia,aswellasprostatecancer,byenlargingtheprostategland.Prostategrowthanddifferentiationarehighlydependentonsexsteroidhormones,particularlyDHT.5α–Reductase(5–AR)deficiencyPatientspresentingwith46XYkaryotypeandfemaleorambiguousgenitaliamaylacktheenzymetestosterone5α–reductase.Thisgenelesioncanresultinpseudohermaphroditism.Thisconditiontypicallypresentswithunderdevelopedmalegenitaliaandprostate.Theseindividualsareoftenraisedasgirlsduetotheirlackofconspicuousmalegenitalia.Intheonsetofpuberty,althoughtheirDHTlevelsremainverylow,theirtestosteronelevelselevatenormally.Theirmusculaturedevelopslikethatofothermaleadults.Afterpuberty,menwiththisconditionhavealargedeficiencyofpubicandbodyhair,andnoincidenceofmalepatternbaldness.5α–reductasedeficiencycanbediagnosedafterpubertybymeasurementoftestosteroneandDHTconcentrations.ExcerptfromtheInstructionsforUseEnzymeimmunoassayforthein-vitro-diagnosticquantitativedeterminationof5alpha-Dihydrotestosteroneinhumanserum.5a-dihydrotestosterone(DHT)isasteroidsimilartotestosteroneandandrostenedione,whichbelongtoaclasscalledandrogens.DHTisaC19steroidandpossessesandrogenicactivity.ThebulkofandrogenproductiontakesplacemainlyintheLeydigcellsofthetestes.Androgenscirculateinthebloodboundtoproteins,especiallysexhormonebindingglobulin(SHBG)andalbumin.Atraceamountofthesesteroidscirculateintheunboundforminthebloodandarereferredtoasthefreefractions.DHThasatleastthreetimesthebindingaffinityforSHBGthantestosterone.Inmalesabout70%ofDHTisderivedfromperipheralconversionoftestosterone,whileinfemalesmostoftheDHTisderivedfromandrostenedione.Themajororgantoneutralizeandrogensistheliver.Thereforeintheliverthesteroidhormonesundergostructuralmodificationsthataregenerallyregardedasprerequisitesfortheirbiologicalinactivation.Somemetabolitesareformedandsomearereturnedtothecirculationbeforerenalexcretion.Therefore,eliminationofsteroidsfromthebodyisdonethroughtheurine.ClinicalTrends:InKlinefelter"ssyndrometheDHTlevelismuchlowerthanthatfoundinnormalmen.Inidiopathichirsutismabout40%ofthepatientshaveanincreasedlevelofDHT.Inpolycysticovaries(PCO)about35%ofthepatientshaveanincreasedDHTlevel.TheDHTlevelinyoungpeopleismuchhigherthanthosefoundinnormalolderpeople,henceandrogenproductionincreasesatpubertywhichgivesrisetomasculinizingcharacteristics.IthasbeendemonstratedthatthehumantestesproduceDHT,whichappearstooriginateintheseminiferoustubules.ThereforeintubulardamagetheproductionofDHTisimpaired,whichcausesadecreaseinthelevelsofplasmaDHT(patientswithgerminalcellaplasiaandazoospermia).ThereisaverylowlevelofplasmaDHTinpatientswithanorchia.Ithasbeenreportedthatinsomeprostatecancer(especiallyinstageD)thedeterminationofDHTcouldbeusefulinpredictingtheresponsetoanti-androgentherapy.ForconcretedatapleaseconsulttheInstructionforUseinthedownloadboxontherightside.