华中科技大学学报（医学版）
華中科技大學學報（醫學版）
화중과기대학학보（의학판）
ACTA UNIVERSITATIS MEDICINAE TONGJI
2010年
1期
102-105,112
,共5页
江远明%肖红俊%何圆圆%杨琛%韦永豪%郑娜%马志跃
江遠明%肖紅俊%何圓圓%楊琛%韋永豪%鄭娜%馬誌躍
강원명%초홍준%하원원%양침%위영호%정나%마지약
螺旋神经节细胞%水杨酸钠%外向延迟整流钾电流%尾电流
螺鏇神經節細胞%水楊痠鈉%外嚮延遲整流鉀電流%尾電流
라선신경절세포%수양산납%외향연지정류갑전류%미전류
spiral ganglion neuron%sodium salicylate%outward delayed rectifier currents%tail currents
目的 采用全细胞膜片钳技术记录耳蜗螺旋神经节细胞(spiral ganglion neurons,SGNs)外向整流钾电流及其尾电流,分析水杨酸钠对耳蜗SGNs外向整流钾电流及其尾电流的影响,初步探讨其耳毒性机制.方法 采用全细胞膜片钳技术记录急性分离并进行细胞短时间(2～3 h)血清培养后,耳蜗SGNs外向延迟整流钾电流及其尾电流曲线,同时记录不同浓度水杨酸钠(0.01、0.1、0.5、1、10 mmol/L)对2种电流的影响.结果耳蜗SGNs上可记录到外向电流,该电流对4-氨基吡啶(4-AP)敏感,证明其为钾电流,该钾电流具有延迟整流特性;1 mmol/L水杨酸钠能明显抑制耳蜗SGNs外向延迟整流钾电流;+50 mV的去极化电压刺激可使最大稳态电流幅值减少(46.3±2.0)%,水杨酸钠对此电流的抑制具有浓度依赖性,外液洗脱后耳蜗SGNs外向延迟整流钾电流可基本恢复正常.另外,可记录出耳蜗SGNs延迟整流钾电流的尾电流曲线;水杨酸钠可降低此尾电流峰值,并缩短尾电流的时间常数,加速尾电流的失活.结论 钾电流在耳蜗SGNs正常电生理活动中有重要作用.水杨酸钠抑制耳蜗SGNs外向整流钾电流及其尾电流,并加速尾电流的失活,这种作用可导致耳蜗SGNs的电生理活动异常,从而引发水杨酸钠对听觉功能的损害.
目的 採用全細胞膜片鉗技術記錄耳蝸螺鏇神經節細胞(spiral ganglion neurons,SGNs)外嚮整流鉀電流及其尾電流,分析水楊痠鈉對耳蝸SGNs外嚮整流鉀電流及其尾電流的影響,初步探討其耳毒性機製.方法 採用全細胞膜片鉗技術記錄急性分離併進行細胞短時間(2～3 h)血清培養後,耳蝸SGNs外嚮延遲整流鉀電流及其尾電流麯線,同時記錄不同濃度水楊痠鈉(0.01、0.1、0.5、1、10 mmol/L)對2種電流的影響.結果耳蝸SGNs上可記錄到外嚮電流,該電流對4-氨基吡啶(4-AP)敏感,證明其為鉀電流,該鉀電流具有延遲整流特性;1 mmol/L水楊痠鈉能明顯抑製耳蝸SGNs外嚮延遲整流鉀電流;+50 mV的去極化電壓刺激可使最大穩態電流幅值減少(46.3±2.0)%,水楊痠鈉對此電流的抑製具有濃度依賴性,外液洗脫後耳蝸SGNs外嚮延遲整流鉀電流可基本恢複正常.另外,可記錄齣耳蝸SGNs延遲整流鉀電流的尾電流麯線;水楊痠鈉可降低此尾電流峰值,併縮短尾電流的時間常數,加速尾電流的失活.結論 鉀電流在耳蝸SGNs正常電生理活動中有重要作用.水楊痠鈉抑製耳蝸SGNs外嚮整流鉀電流及其尾電流,併加速尾電流的失活,這種作用可導緻耳蝸SGNs的電生理活動異常,從而引髮水楊痠鈉對聽覺功能的損害.
목적 채용전세포막편겸기술기록이와라선신경절세포(spiral ganglion neurons,SGNs)외향정류갑전류급기미전류,분석수양산납대이와SGNs외향정류갑전류급기미전류적영향,초보탐토기이독성궤제.방법 채용전세포막편겸기술기록급성분리병진행세포단시간(2～3 h)혈청배양후,이와SGNs외향연지정류갑전류급기미전류곡선,동시기록불동농도수양산납(0.01、0.1、0.5、1、10 mmol/L)대2충전류적영향.결과이와SGNs상가기록도외향전류,해전류대4-안기필정(4-AP)민감,증명기위갑전류,해갑전류구유연지정류특성;1 mmol/L수양산납능명현억제이와SGNs외향연지정류갑전류;+50 mV적거겁화전압자격가사최대은태전류폭치감소(46.3±2.0)%,수양산납대차전류적억제구유농도의뢰성,외액세탈후이와SGNs외향연지정류갑전류가기본회복정상.령외,가기록출이와SGNs연지정류갑전류적미전류곡선;수양산납가강저차미전류봉치,병축단미전류적시간상수,가속미전류적실활.결론 갑전류재이와SGNs정상전생리활동중유중요작용.수양산납억제이와SGNs외향정류갑전류급기미전류,병가속미전류적실활,저충작용가도치이와SGNs적전생리활동이상,종이인발수양산납대은각공능적손해.
Objective To investigate the effects of sodium salicylate on outward delayed rectifier potassium currents(I_(KDR))and their tail currents(I_(K-tail))in isolated spiral ganglion neurons(SGNs)using patch-clamp technique and to inquire into the toxic mechanism.Methods After acute isolation and cell culture in serum for short time(2-3 h),the SGNs' curves of the I_(KDR)and I_(K-tail) were recorded using whole cell patch-clamp technique.The effects of different concentrations of sodium salicylate(0.01,0.10,0.50,1.00,and 10.00 mmol/L)on the current curves of SGNs were observed.Results Because of its sensitivity to 4-AP,the outward current which could be recorded in SGNs was proved to be the potassium current(I_K).The I_(KDR) could be inhibited with 1 mmol/L sodium salicylate obviously.The maximal magnitude of I_(KDR) was decreased by(46.3±2.0)% after given the depolarized stimulation of +50 mV.Besides,the inhibitory effects of sodium salicylate on I_(KDR) were concentration-dependent,and I_(KDR) of SGNs could mostly recover to its normal level after washed out.The curves of I_(K-tail) in SGNs were recorded,and the peak of I_(K-tail) and time constant were reduced,and deactivation was accelerated with sodium salicylate.Conclusion The I_K played an important role in the normal electrophysiological activity of SGNs.But through inhibition of the I_(KDR) and I_(K-tail) and acceleration of I_(K-tail) deactivation,sodium salicylate could induce the electrophysiological abnormality of SGNs to damage the acoustic function.
