简介:Toelucidatethemechanismofphotodynamicdamageofcells,theeffectofHPDpluslightontranscriptlonalectlvltyInthemucleusIsolatefromthenormalratliverwasstudiedinvitorby3H-UTPincorporationintoRNA.MeasurementsoffluorescencespectrumshowedthatHPDwasboundtothenucleusanditsfluorescenceIntensityIncreasedwiththeIncreaseofHPDconcentration.TheexperimentalresultsIndicatedthatnochangescouldbeobservedwheneitherHPDorlightwasusedalone.WhereasthenucleartranscriptionactivitywasfoundtobeinhibitedsignificantlybybothHPDandlighttreatment,andthedegreeofInhibitionwasdependentontheHPDconcentrationandthetimeofexposuretolight.Aftertreatmentby3μg/mlHPD,theinhibitionrateofthenucleartranscriptionactivitywas23%,45%,69%,80%and90%,respectivelyforlightexposureof2,5,10,20and30minutes.Ourresultssuggestedthatdose-dependentdecreasesinthenucleartranscriptionactivity,andmarkedinhibitionofthe
简介:AmethodisdescribedwhichpermitstransmissionelectronmicroscopeofsinglecellstreatedwithHpDpluslasermicroirradiation.Thepreselectedsinglecellthatwasirradiatedbylaserunderlightmicroscopeandfollowedfixation,embeddedandsectioningisexaminedunderelectronmicroscope.Theresultsdemonstratedthatatthelightdoseof1.88ml/μm2notonlytheirradiatednucleolusappearedtransparentregion,buttheotherpartssuchasnon-irradiatedmitochondriaincytoplasmcanalsobedamaged.Whenpartialcytoplasmisirradiatedwiththelightdoseof4.50ml/μm2,thedamagesappearinallcytoplasm,butthereislittlechangeinthenucleus.Theexperimentalresultsalsodemonstratethatcytoplasmismoresensitivethannucleus.ItisthemitochondriaincytoplasmthatareverysensitivetoHpDpluslaser.