简介：Objective:Toobservetheeffectofelectroacupuncture(EA)onsynapticstructureofhippocampalnervefeltsandsynaptophysin(SYN)expressioninratswithcerebralischernicinjury.Methods:SixtyWistarratswererandomizedintoshah-operationgroup,cerebralischemia(CI)groupandEAgroup,eachofwhichwasfurtherdividedinto1week(W)and5Wsubgroups.Clinjurymodelwasestablishedbyocclusionofthebilateralcomrnoncarotidarter-ies.“Baihui”(百会GV20),“Dazhui”(大椎GV14),“Renzhong”(人中GV26)and“Guenyuan”(关元CV4)werepuncturedandstimulatedelectrically.Thebraintissuesectionscontaininghippocampusregionwerestainedwithirnrrunohistochernicaltechniqueandobservedunderlightmicroscopeandtransmissionelectronicmicroscope.Results:AfterCI,theischemicinjuryasdegenerationofthepresynapsecompositions,decreaseofthesynapticnumeraldensity,andlowexpressionofSYNwereobservedinhippocampalCA1area.Bythe5^thweekafterCI,theneonatalsynapsesofCIandEAgroupsappeared,andSYNexpressionwasupregulated.InEAgroup,therecoveryofthenumeraldensityofsynapseswasespeciallynoticeable,being93.8%ofthatofsham-operationgroupandsignificantlyhigherthanthatinCIgroup(P<0.01).Comparedwithsham-operationgroup,thecalibratedopticaldensity(COD)valuesofSYNincreasedto70%inCIgroup,and93.3%inEAgroup,andCODvalueinEAgroupwassignificantlyhigherthanthatinCIgroup(P<0.01).Conclusion,EAcanfunctioninpromotingsynapticregenerationandenhancingandperfectingtheactionsofthereconstructedsynapsesinhippocampalCA1areainCIrats.

简介：BACKGROUND:Synapsesundergohighlevelsofplasticitywithinthenervoussystem,andcerebralischemiainducessynapticplasticitychanges.OBJECTIVE:Todemonstratetheeffectsofelectroacupunctureonultrastructuralsynapticchangesinthefocalcerebralischemiamarginalzoneinratsusingquantitativeanalysisofstereologicalmeasurement.DESIGN,TIMEANDSETTING:Arandomized,controlled,animalexperimentwasperformedattheExperimentalAnimalCenterandLaboratoryofElectronMicroscopy,GuangzhouUniversityofTraditionalChineseMedicinefromJanuary2008toJanuary2009.MATERIALS:TheG-6805electricacupunctureapparatuswasprovidedbyShanghaiHuayiInstrumentFactory,China.METHODS:Atotalof90male,Wistarratswererandomlyassignedtosham-surgery,model,andelectroacupuncturegroups,with30animalsineachgroup.Eachgroupwassubdividedinto1hour,aswellas1,3,7,and21dayspost-surgerygroups,withsixanimalsassignedtoeachtimepoint.Heatcoagulation-inducedocclusionofthemiddlecerebralarterywasperformedtoestablishamodeloffocalcerebralischemia.Electroacupuncturewasappliedimmediatelyfollowingsurgerytotheelectroacupuncturegroup[4/20Hz,2.0-3.0V,1-3mA,toBaihui(GV20)andDazhui(GV14)]for30minutes.Treatmentwasperformedonceaday,andexperimentalanimalsweresacrificed,at1hour,aswellas1,3,7and21dayspost-surgery.MAINOUTCOMEMEASURES:Atdifferenttimepointsafterintervention,changesinsynapticultrastructure,suchaspostsynapticdensitythickness,synapticcleftwidth,andsynapticinterfacecurvature,wereobservedinthefocalcerebralischemiamarginalzoneinratsthroughtheuseoftransmissionelectronicmicroscopy.RESULTS:Brokensynapseswereobservedfollowingcerebralischemia,andthenumberofsynapseswassignificantlydecreased.Comparedtothemodelgroup,synapticultrastructurewassignificantlyimprovedintheelectroacupuncturegroup.Comparedtothesham-surgerygroup,postsynapticdensitythicknesswassignificantlydecreased,asweresynaptic

简介：PreliminaryworkbyourresearchteamrevealedthatSchisandra,arenownedtraditionalChinesemedicine,causeslearningandmemoryimprovementsinovariectomizedmice.ThisactivitywasattributedtoactiveingredientsextractedwithN-butylalcohol,namedSchisandraN-butanolextract.Inthisstudy,ovariectomizedmicewerepretreatedwithSchisandraN-butanolextractgivenbyintragastricadministration.Thistreatmentledtotheenhancementoflearning,andanincreaseinhippocampalCA1synaptic,surfaceandpostsynapticdensity.Adecreaseintheaveragesizeofthesynapticactivezonewasalsoobserved.TheseexperimentalfindingsshowingthatSchisandraN-butanolextractimprovedsynapticmorphologyindicateanunderlyingmechanismbywhichtheabilityoflearningisenhancedinovariectomizedmice.

简介：Membranedepolarizationinducesthereleaseoftheserineproteinasetissue-typeplasminogenactivator(tPA)fromthepresynapticterminalofcerebralcorticalneurons.OnceinthesynapticcleftthistPApromotestheexocytosisandsubsequentendocyticretrievalofglutamate-containingsynapticvesicles,andregulatesthepostsynapticresponsetothepresynapticreleaseofglutamate.Indeed,tPAhasabidirectionaleffectonthecompositionofthepostsynapticdensity(PSD)thatdoesnotrequireplasmingenerationorthepresynapticreleaseofglutamate,butvariesaccordingtothebaselinelevelofneuronalactivity.Hence,ininactiveneuronstPAinducesphosphorylationandaccumulationinthePSDoftheCa~(2+)/calmodulin-dependentproteinkinaseIIα(pCaMKIIα),followedbypCaMKIIα-inducedphosphorylationandsynapticrecruitmentofGluR1-containingα-amino-3-hydroxy-5-methyl-4-isoxazolepropionicacid(AMPA)receptors.Incontrast,inactiveneuronswithincreasedlevelsofpCaMKIIαinthePSDtPAinducespCaMKIIαandpGluR1dephosphorylationandtheirsubsequentremovalfromthePSD.TheseeffectsrequireactivesynapticN-methyl-D-aspartate(NMDA)receptorsandcyclin-dependentkinase5(Cdk5)-inducedphosphorylationoftheproteinphosphatase1(PP1)atT320.ThesedataindicatethattPAisahomeostaticregulatorofthepostsynapticresponseofcerebralcorticalneuronstothepresynapticreleaseofglutamateviabidirectionalregulationofthepCaMKIIα/PP1switchinthePSD.

简介：摘要ObjectiveThe present study aimed to investigate the effects of rTMS on astrocytic polarization during cerebral ischemic/reperfusion injury.MethodsThree rTMS protocols were applied to primary astrocytes under normal and oxygen-glucose deprivation/reoxygenation (OGD/R) conditions. Cell survival, proliferation, and phenotypic changes were assessed after 2-day treatment. Astrocytes culture medium (ACM) from control, OGD/R, and OGD/R + rTMS groups were mixed with neuronal medium to culture neurons for 48 h and 7 days, in order to explore the influence on neuronal survival and synaptic plasticity. In vivo, rats were subjected to middle cerebral artery occlusion (MCAO), and received posterior orbital intravenous injection of ACM collected from different groups at reperfusion, and at 3 days post reperfusion. The apoptosis in the ischemic penumbra, infarct volumes, and the modified Neurological Severity Score (mNSS) were evaluated at 1 week after reperfusion, and cognitive functions were evaluated using the Morris Water Maze (MWM) tests. Finally, the 10 Hz rTMS was directly applied to MCAO rats to verify the rTMS effects on astrocytic polarizationResultsAmong these three frequencies, the 10 Hz protocol exerted the greatest potential to modulate astrocytic polarization after OGD/R injury. Classically activated and A1 markers were significantly inhibited by rTMS treatment. In OGD/R model, the concentration of pro-inflammatory mediator TNF-α decreased from 57.7 to 23.0 pg/mL, while anti-inflammatory mediator IL-10 increased from 99.0 to 555.1 pg/mL in the ACM after rTMS treatment. The ACM collected from rTMS-treated astrocytes significantly alleviated neuronal apoptosis induced by OGD/R injury, and promoted neuronal plasticity. In MCAO rat model, the ACM collected from rTMS treatment decreased neuronal apoptosis and infarct volumes, and improved cognitive functions. The neurotoxic astrocytes were simultaneously inhibited after rTMS treatment.ConclusionsInhibition of neurotoxic astrocytic polarization is a potential mechanism for the effectiveness of high-frequency rTMS in cerebral ischemic stroke.

简介：ObjectiveToinvestigatetheearlychangeofcochlearribbonsynapsesoninnerhaircellsinresponsetoaminoglycosideototoxicity.MethodsC57BL/6Jmicereceivedintraperitonealinjectionofgentamicin(100mg/kg/day),andtheapicalcoilorganofCortiwasexaminedonthe4th,7thand10thday(n=10).Litter-mateswithoutgentamicintreatmentservedascontrols(n=10).RIBEYEonthepresynapticmembraneandAMPAreceptorsonthepostsynapticmembranewerelabeledwithCtBP2orGluR2/3respectively.Threedi-mensionreconstructionwasconductedusingthe3DSMAX8.0software.ResultsTherewerenodisruptionsofouterorinnerhaircellsinallgroups.However,thenumberofribbonsynapsesoncochlearinnerhaircellsincreasedsignificantlywithin7daysaftergentamicinexposure(P<0.01),followedbyasignificantde-creaseafter7days.ConclusionDuringtheearlystageofaminoglycosideototoxicity,increasedpopulationofcochlearribbonsynapsesmayindicateasignificantdown-regulationofsynapticfunction.

简介：由地可配置的nanogranularSiO2的基于的离子/电子的混合synaptic晶体管gated拍摄的indium–zinc-oxide(IZO)被报导。设备展出了上面的高当前的开／关比率107,∼14cm2V−1s−1和∼80mV/decade的一个低次于最低限度的秋千。门偏爱将在隧道/电介质接口调制在质子和电子之间的相互影响。由于在nanogranularSiO2电影以内的短暂质子流动的动态调整，隧道电流将动态地被修改。短期的synaptic粘性例如短期的potentiation和短期的消沉，在建议IZOsynaptic晶体管上被模仿。结果显示这里建议的synaptic晶体管在未来neuromorphic设备有潜在的应用。