沙棘总黄酮对豚鼠心室乳头状肌和培养大鼠心肌细胞的电生理作用

沙棘总黄酮对豚鼠心室乳头状肌和培养大鼠心肌细胞的电生理作用 沙棘总黄酮对豚鼠心室乳头状肌和培养大 鼠心肌细胞的电生理作用 BIBLID?IssN0253—9756ActaPharrnacologicaSknira中国药理 EIectr0physi0l0giceffectsoftotalflavonesofHippophaerhamnoidesL oHguineapigpapillarymusclesandculturedratmyocardialcells WUJie,YUXiao’Jiang,MAXin,LIXiaoGuang,LIUDong (ElectrophysiologyLaboratory,XianMedicalUniversity,Xi’an710061,Ch ina) ABSTRACTTheeffectsoftotalflavouesof HippophaerhamnoidesL(TFH)wereevalu— atedusingconventiohalmicroelectr0deteeh— nic.AfteradministrationofTFH100——200 mg?L-.,theactionpotentialdurationof 50repolarization,(APD5o)wasshortened bothinculturedratmyocardialcellsandin guineapigpapillarymuscles.Theslopeof phase4ofdepolarization(SP.)inculturedrat myocardialcells?_丑sdecreasedandthecon— tractileforce(CF)inguineapigpapillary muscles—asweakened.Arrhythmiasevoked bystrophantinGinguineapigpapillarymu$ elesweresuppressedbyTFH100mg?L-i. Thesefindingssuggestedthattheinfluenceof TFHonmyocardialcellsmayberesulted mainlyfromitsinhibitionofCainfluxand itsinterferencewithintracellularCa”reser vojr. KEYWORDSHippophaerhamnoidesL flavones;papillarymuscles;cuhuredcells actionpotentials;ouabaintarrhythmia ThetotalflavonesofHippophaerham? noidesL(TFH)exertedananti—arrhythmic actionwhichwasprohablyrelatedtotheinhi bitionofCa抖channel”?Inordertodeter. tt~ineitsbnicandelectricmeehanisms.we studiedtheelectrophysiologiceffectsofTFH onguineapigpapillarymusclesandcultured ratmyocardialeelIs. MATERlALSANDMETH0DS sexes)werekilledbyaheavyblowonthehead.Pap- illarymusclesweexcisedfromtherightventricle andpinnedtoarecordingchambercontaining50mIof Tyrodes~lution(NaC1136,KCI5?4,Mga21.05t CaCI11.8,andglucose11mmo]?L,pH72--74) at35?andgassedwithoxygen10ndJmin一.Af- terane口uilibrationperiodof1h,themusclewasstim— ulatedthroughabipolarplatinumelectrodewithpuls- esof2一msduration,deliveredat15timesthreshold voltageatafrequencyof1Hz. Primaryculturesofratmyoeardialee1Iswereis0f 1atedfrom2-4一day-oldWistarrat8bythemethodof Wenzel,Wheatley.andByrd.Theheartswereex— cisedunderasepticcondition.Afterremova1ofthe blood,thelowertwo?thirdsoftheventeie1e8’?eTcut intosmallpiecesThefragmentswerewashedtwice inaflaskofcaLcium?freeandmagnesium-freephos— phatebuffersolution.Thenthefragmentsweredi- gestedtwiceinthepresenceof0.06trypsinsblu- tion,1Omineachtimeat37?.Thesuperabundant wasdiscardedandEagle’sculturemediumcontaintng 20fetalcalfserumwasadded.Theeu【tureswere incubatedat37?incultureflasksfor5dbefore study. Transmembraneactionpotentialswererecorded using3mol?LKCIfilledglassmicroeleetrodes.tD diametertessthanO.5tim,anddisplayedontheupper lineofCOS502Ooscilloscope.ThemaximalIrateol depolarization(,),0btainedbyelectronicdifferen— tiator,andthecontractileforce(CF)weshownon theIowerIineoftheoscilloscopeinturn.Theeffee. tirerefractoryperiod(ERP)wa3determinedbymea- suringtheshortestintervalbetweenanextrastimulus andaregularstimuIus. Dataweremeasuredbyphotograph.Allresurts wel-eexpressedas士s.Statlsticalanalysiswa3per. formedusingtest. Fortyguineapigsweighing250士20g(bothRESULTS Receivedl991—07—05Acceptedl994—03l4EffectsORelectricactivitiesofcullured 342?BIBLID:ISSN02539756ActaPharmacologicaSinica中国药理 1994Jut;15(4) ratmyocardialcellsandguineapigpapillary muscleTheculturedcellswithspontaneous— lyfiringactionpotentials(AP)werechosen. InthepresenceofTFH10Omg?l_,.the APD5.wasshortenedandtheSP4wasremark— ablydecreased.Uponfurtherincreasingthe concentrationofTFHto200mg?L.a shorteningofAPD9wasseefl(Tab1). Onguineapigpapil!arymuscle.TFH100 200mg?L叫shortenedtheAPD;and weakenedtheCF(Tab1). Effectsonarrhythmiasinducedbystro— phantinGinguineapigpapillarymuscleAf teranequilibrationfor1h,actionpotentials wereelicitedbythestandardtrainstimulation withrectangularpulsesof0.5——1.0msdura tionandanamplitudeof1.5threshold. Theoscillatoryafterpotentialswereevoked bytheadditionofstrophantinG0.4”m0l ? I一’.TFH100mg?Lledtothedisap pearanee0foscillatoryafter—potentialsfroma controlamplitude0f7.1?0.8mVwithin15 mininthe8preparationsstudied(P<0.01). Aftertheactionpotentialswereelicited bystimulation,strophantinG0.8~tmol?I wasadded.Spontaneouselectricactivities wereinducedbygraduallydecreasingthe stimulationfrequencydowntocompletecessa tion.After5min.inthepresence0fTFH 10Omg?L’,therateofspontaneouselectric activitywasdecreasedfrom196土17bmpto 67土9bpm(P<0.01). WhenbothstrophantinG0.8”moI?L andTFH100mg?Lwereaddedatthesame time,oscillationsdidnotappearinthetested preparations. DISCUSS10N 0urexperimentdemonstratedthatTFH 200mg?LshortenedtheAPDandlessened theSP4inculturedmyocardium.Thisresult indicatedTFHblockedthetransmembrane Cainflux.However.inourpreparation. thesignificantdecreaseexpectedinAPAand V…wasnotpbservedsinceCa.wasshownto beinvolvedinthecurrentunderlyingtheup strokeofAPandthepacemakeractivityin culturedmyocardium”.Assumptionisusti— fledthatTFH.attheconcentrationof200mg ? L’,onlypartiallyinhihiredthetransmem- braneCainfluxanddidnotaffectthe Tab1-EffectsoftotalflavonesofHippophaerhamnoidesL(TFH)oRelectrica ctivitiesofculturedratmyocar— dialcellsandguineapigpapillarymttsclesn—l0, 士.’P>O.05,P<O.05.P<O.O1ypriortoTFH administration. AP:actionpotentials;APD50andAPD=actionpotentialdurationat50and90 repo[arizatio}Vm一maxi malrateofdepolarization;SP’:slopeofphase4;ERP=effectiverefractoryper iodICF—contractileforce. BIBIID.ISSN02539755ActaPha~acologlcaSLinea中目药理 1994Jul;15(4)?343 currentdeterminingupstrokeofAPincul turedmyocardium.Inguineapigpapillary muscles,ourfindingsalsoconfirmedthatTFH exertedablockadeeffectonthetransmem braneCainflux.BecauseTFHrestricted thecontractileforceand.inthemeanwh-Ie, iustahhreviatedtheplateauofAPwithout influencingtheotherparameters’. Inaddition,wefoundTFHcouldantago nizearrhythmizsinducedbystrophantinG whichwereprovedtoberelatedtotheintra— cellularCaoverloadandatransidentoseilla- torymovementofCareleasedfromthesar— eoplasmreticulum’”.Therefore,itislikely arrhythmiceffectofTFHwasalso thatanti— resultedfromtheinhibitionoftransmembrane Ca”influxaswellasthejnterfereneeofthe intracellularCareservoir,sareoplasmreticu— lum.Inthispaper,wecannotruleOUtthe possibilitythatinculturedmyoeardiumtheah senceofchangeinupstrokeofAPwasdueto thedeficiencywhichwedidnotmakefurther studyathigherconcentrationsofTFH. REFERENCES 1L[uFM,LlZX,SIl【S.Effectsoftota【啊……ofHip- pophaerhamncddesl叻culturedrathartceilsandoQ cAMPlevelandadenyl&recyclaseinmyocard[um. ACtRPharmaeolSInl988I9539—43. 2LiuFM,I.iZX,ShiS.Antiarrhythtmceliotoftotal ftavonesofHiffT~ophaserha…ideILnthe[sotated heart.CbinPharnmco【BulJ1989;5{44—7 3WeberDG,WheatleyJW,ByrdGn Effectsofmcotineonculturedr&theartcells. Toxico】ApplPhar~co【1970|17i774—85. 4Ferr[erGR.DigLtat[sarrhythmLas:roleof~c[1latoryaf- terpotentLats.ProgCardiovascDtsl977;19:459—74. jSchanneOF.Ruiz—Ce~ttiE,PagetMD,Des】丑ur~rsY InfluenceofvarLed[ca”_]arm[Na]onelectricalact[vi— tvofclustersofcuLturedcardiaceellsfrom…atalrats. JMo【Cet【CardLoll979{11:477—84. 6FteckensteinA.Specificpharmacologyofcalciuminmy- ocardLum?rdLacpa~makers,andvascularsmoothmHs— cle.An…RevPhacolToxica【1977{11:l49—66. 7JanuaryCT,FotzardHA.DeLayedafterdepolaxi~ations Lnheartmuscle.mechanismsand~levance PharmacolRevl988;40j219—27., 一 ;4号 沙棘总黄酮对豚鼠心童乳头状肌和 培养大鼠心肌细胞的电生理作用力S. z 吴捷,于晓江,马欣,李光,刘东 (西安医科大学电生理研究室,西安710061,中国) ,1/c1摘要用传统微电技术研究了沙棘总黄酮 (TFH)对心肌细胞的电生理作用.TFH100 — 200mg?L使豚鼠心室乳头状肌APD缩 短,收缩力下降,培养大鼠心肌细胞APD缩短 及4相除极斜率降低.TFH100mg?L可抑 制毒毛花甙G诱发豚鼠乳头状肌心律失常. 提示,上述作用主要与TFH抑制心肌细胞 Ca内流影响心肌细胞内Ca储库有关. 乳头状肌;培养的 心律失常 The3rdCongressofFederationofAsian&OceanianPhysiologicalSoci eties 1994Nov7--10Shanghai PleasecontactProfessorYANGXion~一Li,PhD,Directort ShanghaiInstituteofPhysiotogy, ChtneseAcademyofSciences, 320Yue—yangR0ad. Shanghai200031.Ch… Phone:8621437—0080.Fax:86—21-433—2445.