Description:

ChromogenixS-2251™isachromogenicsubstrateforplasminandstreptokinase-activatedplasminogen.Thesubstratehasbeenusedforthedeterminationof:

• Antiplasmininplasma
• Plasminogeninplasma

Composition:

EachvialcontainschromogenicsubstrateS-2251™,25mgandmannitol60mgasabulkingagent.StABIlity:Substance:Stableuntilexpirydateifstoredat2-8°C.Avoidexposuretolight.Thesubstanceishygroscopicandshouldbestoreddry.Solution:3mmol/LinH2Oisstableforatleast6monthsat2-8°C.Contaminationbymicroorganismsmaycausehydrolysis.

Chemicalname:H-D-Valyl-L-leucyl-L-lysinep-Nitroanilinedihydrochloride

Formula:H-D-Val-Leu-Lys-pNA·2HCl

Mol.wt:551.6

PlasminogenandPlasminIUandEnzymeActivity:

Plasminogen(MW:92Kda)isthezymogenformofplasmin(83KDa).

Theactivationofplasminogenisaccomplishedbyt-PA,urokinaseorstreptokinase.

Itisnotthepurposeofthistexttodescribethemechanismsofactivationofplasminogenanditsinhibition,butitisimportanttounderlinethattheycanaffectthereactionoftheactiveenzymewithchromogenicsubstrates,caseinorfibrin.

FormoreinformationrefertoGaffney(1).

1mlofnormalplasmacontainsabout180µgor2nmolofplasminogen.Theactivityofplasminogencanbeexpressedincaseinunits(CU)e.g.forexampletoSgourisetal.(2).

Friberger(3)foundthattheamountofplasminogenin1mlofnormalplasmacorrespondsto3.8CU,asdeterminedbythechromogenicmethoddescribed(streptokinaseactivatedplasminogen).

TheChromogenixplasminogenreagentwhenactivatedwithstreptokinaseshowsanactivityof 7.3nkatchromogenicsubstrateS-2251™perCU.

In1983Friberger(4)reportedthat1µgofplasmincorrespondsto0.20nkatchromogenicsubstrateS-2251™,orto0.024CUorto0.028CTA-U.

In1975,thefirststandardforplasminwasestablished(5)andtheinternationalunitwasdefinedequivalenttoCTA-U(5-6).

Thiscontainedapurifiedhumanplasminin50%glycerol.WhentestedbyFribergeretal.(7),itshowedaboutthesameactivityastheKabipreparationintermsofµmolofsubstratehydrolysedperminuteperunitofenzyme. Sincethenthedifferentaspectsofcaseinolytic,amidolyticandfibrinolyticactivityhavebeenexploredindetailsand,thediscrepancybetweenamidolyticandfibrinolyticactivityinreferencepreparationswasunderlinedasinthecaseofthe2ndInternationalReferencePreparationofplasminin1983(8).

Thecurrent3rdInternationalStandardforplasmin,97/536wasestablishedin1998,andtheresultspresentedattheFibrinolysisSubcommitteeoftheScientificandStandardizationCommitteeoftheInternationalSocietyofThrombosisandHaemostasis(Ljubljana,Slovenia,June1998).The2ndInternationalReferencePreparationwasusedasreferencematerialandachromogenicassaywasthemethodused.ThereisnoestablishedWHOstandardforplasminogen,buttheNationalInstituteforBIOLOGicalStandardsandControl,establishedtheIstBritishReferencePreparation,78/646(9).

ItisapreparationofGlu-plasminogen,assayedbyfibrinolyticandchromogenicmethodsagainstthe2ndInternationalStandardforplasmin.Completeactivationofplasminogenwasachievedbybothurokinaseorstreptokinaseandtheactivitywascomparabletothatofthereferencepreparationofplasmin.

1. GaffneyPJ.
   Standardizationofplasminogenassays.Haemostasis18Suppl.1,47-60(1988).
2. SgourisJTetal.
   Thepreparationofhumanfibrinolysin(plasmin).VoxSang5,357-376(1960).
3. FribergerPandKnosM.
   Plasminogenactivationinnormalplasma.In:Chromogenicpeptidesubstrates,Eds,ScullyMFandKakkarVV,ChurchillLivingstone,128-140(1979).
4. FribergerPetal.
   Syntheticpeptidesubstrateassaysandfibrinolysisandtheirapplicationonautomates.In:SeminarsinThrombosisandHaemostasis,Vol.9,281-300(1983).
5. KirkwoodTBetal.
   Astandardforhumanplasmin.
   ThrombDiathHaemorrh34,20-30(1975).
6. 28thReport,WHOExpertCommitteeonBiologicalStandardization.WHOTechRepSerNo610;1977,pp13.
7. FribergerPetal.
   Anewspecificsubstrateforthedeterminationofplasmin.In:Chromogenicpeptidesubstrates,Eds,ScullyMFandKakkarVV,ChurchillLivingstone,121-127(1979).
8. GaffneyPJandMussettMV.
   Internationalcollaborativestudyfortheestablishmentofthesecondinternationalreferencepreparationofplasmin.ThrombHaemost50,645-649(1983).
9. GaffneyPJandCurtisAD.
   Theestablishmentofastandardforplasminogen.ThrombHaemost51,376-378(1984).