Postnatal development of catecholamine uptake and storage of the newborn rat heart☆
[摘要] TheabilityofatriaandventricularslicesofheartremovedfromSprague-Dawleyratsatages1–21daystotakeupandstorecatecholamineswasstudiedtocorrelatethisactivitywiththepreviouslyobservedphysiologicimmaturityofthecardiacsympatheticnervoussystemintheneonatalmammal.Totaluptakeandsubcellulardistributionat1,4,7,14,and21daysweredeterminedatvarioustimeintervalsbetween5and30min.Intheartriatherewasasmallamountofuptakeobservedduringthefirstpostnatalday,whichincreasedonlyslightlyby4daysofage.Thegreatestchangeoccurredbetween4and7days.Uptakesat7,14,and21daysweresimilartoadultvalues.Reserpineinhibitedthe30-minuptake57%duringthefirstdayoflife,increasingto69%inhibitionby7daysofage.Uptakeofnorepinephrineintotheventricularslices,bothwithandwithoutreserpine,waslessateachagepointuntil14daysofage,atwhichtimeitequaledatrialuptake.Theuptakeandtheeffectofreserpineintheparticulatefractionofhomogenatefrombothatriaandventricularslicesparalleledthedevelopmentalpatternseenintheslice.ApplicationofMichaelis-Mentenkineticstouptakeat4and7daysrevealedacommonKmbutdifferingVmax.Thesestudiessuggestthattheincreasesintheabilityofthedevelopingrathearttoaccumulatenorepinephrineisduetoincreasesinthenumberorstoragecapacityofsynapticvesicles.
[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]
