Release of respiratory control by 2,4-dinitrophenol in different stages of sea urchin development☆
[摘要] TheaimofthisresearchwastostudytherespiratorycontrolindifferentstagesofearlydevelopmentuntilthepluteusstageoftheseaurchinsParacentrotuslividusandPsammechinusmiliaris.Itwasstartedfromthewell-establishedfactthatcertainlowconcentrationsof2,4-dinitrophenol(DNP)releaserespiratorycontroltomaximalextent.TherespiratoryrateinthepresenceofDNPgivesthusthecapacityoftherespiratorysystemofthecellsexamined(cf.uppercurvesinFigs.2and3).Therespiratorycontrolratio(theDNP-releasedoverthenormalrespiratoryrate)wascalculatedinagreatervarietyofmaterial(Figs.4and5,Table2).Theratioishighintheearlypostfertilizationstagebutdecreasesrathersteeplyduringthefirstdevelopmentalperiod(fromfertilizationtotheonsetofthemesenchymeblastulastage).Duringthesecondperiod(fromthemesenchymeblastulatothepluteusstage)theratioremainsalmostconstantorshowsaslopemuchlesssteepthaninthepreviousperiod.Theexponentialriseofrespiratoryrateoccurringinthefirstdevelopmentalperiodmeansapartialreleaseofrespiratorycontrol.Inviewofcurrentexperiencefromstudiesonmitochondrialsystemsitispostulatedthatthepartialreleaseresultsfromanincreasedformationofphosphateacceptorsduetotheutilizationofenergy-richphosphateforsynthesesofembryoniccomponents.TherespiratoryrateprevailinginanearlypostfertilizationstageofParacentrotuseggswaslowerinthewinterandearlyspringthaninthelatespring.Neverthelesstherespiratorycontrolratioshowednosignificantvariationwhenthetwoperiodswerecompared.Therespiratorychangesoccurringuponfertilizationarebrieflydiscussed.
[发布日期] [发布机构]
[效力级别] [学科分类] 生物科学（综合）
[关键词] [时效性]
