摘要
作者观察了严重早期烧伤及假伤(正常)血浆提取物(分别以BPT及NPE表示)对离体灌流正常豚鼠乳头肌细胞电活动的影响。结果发现:高、中、低3种浓度的BPT,①均可使静息电位减小,其时程曲线略呈“S”形,其潜伏期有明显的浓度依赖性;②均可引起乳头肌节律不整的自发兴奋;③高浓度BPT明显使动作电位幅度(APA)降低,中、低浓度的BPT对APA及最大除极速度均无明显影响;④BPT对复极化时程APD10的影响不大,但使APD50及APD90显著延长,使动作电位波形在复极化初期出现明显的凹陷和平台期延长;⑤高浓度NPE有相当于低浓度BPT的生物效应。提示BPT可能直接影响心肌细胞K+、Ca2+的转运。
Theefectsofplasmaextractofnormal(NPE)andburned(BPT)guineapigsonbioelectricactivityofisolatednormalguineapig′spapilarymusclewereobservedandcompared.Theburnedanimalssuferfor35%fulthicknessburninjury.After8hthere-sultsareshownasfolows.1.AlBPTofhigh,middleandlowconcentrationsandNPEinhighconcentratonsygnificantlydecreasetherestingpotential(RP).ThevariationoftimecourseofRPexpressesastheshapeof“S”.Thereisanobviousconcentrationdependencefortheresponselatency.2.ThearrhythmicspontaneousexcitationmaybeevokedbyeitherBPTofthreeconcentrationsorNPEinhighconcentration.3.ThehighconcentrationofBPTdecreasestheamplitudeofactionpotential(APA)obviously,otherBPTconcentrationsandalNPEhavenoefectonAPAandmaximaldepolarizationrate(Vmax).4.BothBPTandNPEhavenoefecton10%repolarizationduration(APD10),butBPTobviouslyprolongedthe50%and90%repolarizationduration(APD50,APD90)respectively.Thewaveformoftheactionpotentialshowedanobviousconcaveatearlyrepolarizationcourseandaprolongedplateau.5.ThebiologicalefectofNPEinhighconcentrationcorespondswiththatofBPTinalowconcentration.TheseresultssuggestthatBPTmaybeabletodirectlyinfluencethetransportofK+andCa2+andmayhavelitleefectonNa+transportacrossthecelmem-brane.
基金
国家自然科学基金