ObjectivesToinvestigatetheeffectandmechanismofendovaseularbraehytherapywith^192IronexpressionoftypeIcollagen,metalloproteinases-1(MMP-1)andthetissueinhibitor(TIMP-1)afterangioplasty.MethodsRestenotiemodelofdomesticmieroswinewasemployedandtheiliaearterieswererandomizedtoradiationgroup(n=12),whichweretreatedwith20-25Gyof^192Ir,andnon-radiationgroup(n=36)afterangioplasty.Thetargetvesselswereharvestedintheendof3monthsand6monthsafterangioplasty.Im-munohistochemistryandinsituhybridizationwereusedtodetectproteinsoftypeIcollagen,MMP-1andTIMP-1,andmRNAexpressionoftypeIcollagen.ResultsTheproteinandmRNAoftypeIcollagen,theratiosofTIMP-1/MMP-1weresignificantlylowerinradiationgroupthaninnon-radiationgroup(P<0.05or0.01).ThepeakoftranscriptionoftypeIcollagenmRNAwasat6monthsand3monthsinnon-radiationgroupandradiationgrouprespectively.ConclusionsEndovascularbrachytherapywith^192IrmightmodifythemetabolismofextracellularmatrixafterangioplastybyinhibitingthesynthesisoftypeIcollagenandtheactivitiesofMMP-1andTIMP-1.
