资源描述：
《ATP和ACH诱发豚鼠外毛细胞CICR的激光共聚焦研究》由会员上传分享，免费在线阅读，更多相关内容在学术论文-天天文库。
1、上海交通大学硕士学位论文ATP和ACh诱发豚鼠外毛细胞CICR的激光共聚焦研究姓名：黄莉申请学位级别：硕士专业：耳鼻咽喉-头颈外科指导教师：杨军200805012+Thapsigargin+ATP分别引起[Ca]i缓慢升高。2+结论:在细胞外液有Ca的条件下，ATP和ACh引起OHC的2+2+[Ca]i升高，除了通过离子通道引起胞外Ca内流，还有IP3敏感钙库2+的释放及诱发CICR。在无Ca的条件下，ATP仍能诱发CICR，其机2+2+制可能是ATP促进IP3敏感钙库释放Ca，Ca又诱发了CICR。而ACh2+2+的反应是C
2、a依赖性的，在细胞外液无Ca的条件下，ACh不能引起IP3敏感钙库的释放和诱发CICR。关键词:ATP,ACh,CICR,外毛细胞,钙,耳蜗ATPANDACHINDUCEDCICRINOUTERHAIRCELLSOFTHEGUINEAPIG:STUDYOFCONFOCALMICROSCOPYABSTRACTObjective：EffectsofATPandacetylcholine(ACh)onintracellular2+2+2+Caconcentrations([Ca]i)andpossiblemechanismofCa-
3、induced2+Carelease(CICR)oftheisolatedouterhaircells(OHCs)intheguineapigcochleawerestudiedwithconfocalmicroscopy.Methods：OHCswereisolatedfromguineapigcochleabyenzymaticandmechanicalmethods.TheeffectsofATP﹑ACh﹑Ryanodine+ATP(orACh)andThapsigargin+ATP(orACh)inthe2+2+pre
4、senceorabsenceofextracellularCaon[Ca]iinOHCswereexaminedbyconfocalmicroscopy.Results：InthepresenceofATP﹑Ryanodine+ATP﹑Thapsigargin+ATP﹑ACh﹑Ryanodine+AChandThapsigargin+ACh2+increased[Ca]iandevokedanevidentwave,respectively,therelativemagnitudeoffluorescencewere1.60±
5、0.01(ATP),1.644±0.005(Ryanodine+ATP),1.491±0.005(Thapsigargin+ATP),1.43±0.01(ACh),1.58±0.02(Ryanodine+ACh),1.398±0.003(Thapsigargin+ACh)inOHCsinthepresenceof2+2+extracellularCarespectively.IntheabsenceofextracellularCa,ATP2+andRyanodine+ATPinducedagradualandsmall[Ca
6、]iwave,therelativemagnitudeoffluorescencewere1.341±0.006and1.386±0.008,however,ACh、Ryanodine+ACh、Thapsigargin+AChand2+Thapsigargin+ATPcannotinducewavebutagradual[Ca]ielevation.2+AChcannotincrease[Ca]i.2+Conclusion:InthepresenceofextracellularCa,ATPandACh2+2+increase
7、d[Ca]iinOHCsnotonlybyCainfluxthroughionchannelon2+cellmembrancebutalsoareleaseofCafromIP3-sensitivecalcium2+reservoirandCICR.IntheabsenceofextracellularCa,ATPactivated2+IP3sensitivecalciumreservoirandCareleasethroughIP3sensitivecalciumreservoir,inturnCICRwasinduced.
8、AChcannotactivateIP32+sensitivecalciumreservoirandCICRintheabsenceofextracellularCa,2+therefore,theeffectofAChwasdependentofextracellularC
