水杨酸钠可逆性抑制耳蜗螺旋神经节神经元GABAa受体电流

目的探讨水杨酸钠对大鼠耳蜗螺旋神经节神经元(SGN)GABAa受体的作用。方法采用全细胞膜片钳记录技术,观察离体培养大鼠SGN的GABAa受体激活电流的特性及水杨酸钠对其作用特点。结果在SGN上可记录到GABAa受体激动剂GABA诱发的内向电流,该电流呈浓度依赖性且可被荷包牡丹碱所阻断;水杨酸钠作用在SGN上未诱出电流,100μM、500μM的GABA与不同浓度的水杨酸钠(500μM、1000μM、5000μM)分别联合作用时,GABA诱发的电流可被不同程度地抑制,且该抑制作用呈可逆性。结论大鼠SGN上可记录到GABAa受体电流,且水杨酸钠以浓度依赖的方式可逆性抑制GABAa受体电流,抑制作用与GABA浓度有关。     

豚鼠耳蜗外毛细胞乙酰胆碱敏感性钾电流特性

目的 研究豚鼠耳蜗外毛细胞乙酰胆碱(acetylcholine,ACh)敏感性钾电流离子特性及其受体的药理学特性.方法 健康豚鼠38只,断头后取出基底膜,经胶原酶Ⅳ消化后获取外毛细胞.采用全细胞记录膜片钳技术检测新鲜单离外毛细胞ACh-敏感性钾电流对细胞外钙依赖性钾电流阻断剂和N型胆碱能受体抑制剂的敏感性.结果 ①细胞外ACh激活一快速去敏感化的外向性钾电流,其平均(-x±s,以下同)反转电位为(-67.3±8.2)mV(n=10);-50 mV钳制电压下,100 μmol/LACh激活电流的幅值为(506.6±186.3)pA(n=9).②ACh-敏感性钾电流对细胞外四乙铵(tetraethylammonium,TEA,10 mmol/L)、蜂毒明肽(apamin,1 μmol/L)敏感,而细胞外的IBTX(iberiotoxin,200 nmol/L)对ACh-敏感性钾电流幅值无抑制作用.③ACh-敏感性钾电流的半数激活浓度(EC50)为(33.5±5.7)μmol/L(n=7).④ACh-敏感性钾电流对细胞外γ-氨基丁酸(gammaaminobutyric acid,GABA)-A受体阻断剂荷包牡丹碱(bicuculline)和α9-N型胆碱能受体(α9受体)特异性抑制剂士的宁(strychnine)敏感.士的宁和荷包牡丹碱对ACh-敏感性钾电流的抑制作用具有浓度依赖性,其半数抑制浓度(IC50)分别为(22.3±2.6)nmol/L(n=7)和(1.2±0.4)μmol/L(n=6).结论 细胞外ACh激活豚鼠耳蜗外毛细胞产生小电导钙依赖性钾电流(SK),此电流可能由α9受体介导.     

光学成像蜗核谷氨酸受体的兴奋性传导

目的在神经细胞群的水平上二维动态观测蜗核(CN)神经元兴奋性谷氨酸递质受体的传导机制.方法自新生小鼠制备脑干切片,用吸光性电压敏感染料RH 155染色,并成像于16×16 elements Photodiode Arrays光学记录系统,电刺激位听神经(第8颅神经,nⅧth)断端.为了观察谷氨酸是否为耳蜗核神经元的兴奋性递质,用受体拮抗剂(NMDA受体拮抗剂APV,non-NMDA受体拮抗剂CNQX)灌流脑片.结果①电刺激nⅧth断端后光学记录显示兴奋传导至CN区域;②CN神经兴奋有激发延迟和高峰延迟,DCN和VCN之间激发和高峰延迟之间比较,差异有显著性意义(P＜0.01);③光学记录可以同步观察氨基酸拮抗剂对多个神经元核团兴奋性传递的作用,NMDA受体拮抗剂APV和non-NMDA受体拮抗剂CNQX对EPSP的抑制作用及其在VCN和DCN的作用方式不同.APV灌流后神经元的EPSP被抑制,计算其减低比率,在VCN为99.10±0.02%(n=18 elements),DCN为76.00±19.20%(n=46 elements).同时,CNQX灌流后神经元的EPSP被抑制,用相同方法计算其减低比率,在VCN为0.90±0.02%(n=18elements),DCN为24.00±19.20%(n=46 elements).结论光学记录膜电位方法可以在神经细胞群的水平上直观观察CN神经电活动的时空二维方式及其兴奋性突触传递过程;药理实验证实,谷氨酸是CN的神经元突触后电位传导的兴奋性递质;谷氨酸两种受体NMDA和non-NMDA均参与介导CN神经元EPSP;NMDA受体和non-NMDA受体的作用在VCN和DCN的不同神经元核团之间有区别.     

可视法脑片膜片钳技术观察大鼠前庭内侧核神经元毒蕈碱样胆碱能受体的电生理特性

目的 建立大鼠前庭内侧核脑片可视法膜片钳实验技术,探讨前庭内侧核神经元毒蕈碱样胆碱能受体(muscarinic cholinergic receptor,M受体)介导电流的生物学特性.方法 选用15只Wistar大鼠用于制备前庭内侧核脑片,应用红外微分干涉相差(infrared differential interference contrast,IR-DIC)技术结合电荷耦合式感光成像(charge coupled device-camera,CCD-camera)系统,在可视法膜片钳全细胞记录模式下对20个正常功能状态的前庭内侧核神经元M受体的通道电流性质进行观察和分析.结果 可视法脑片膜片钳技术可对神经元直接进行准确定位和功能状态的筛选.前庭内侧核神经元给予毒蕈碱后电流-电压(I-V)曲线斜率增加,毒蕈碱引发效应电流的反转电位为(-88.4±4.9)mV((-x)±s,下同),表明M受体去极化效应是由钾电导的减少所介导;M受体介导电流的电压敏感性测试显示:毒蕈碱引发的效应曲线呈线性关系,反转电位为(-86.7±3.5)mV,提示毒蕈碱所阻断的钾电流为非电压敏感性的漏钾电流.结论 可视法脑片膜片钳实验技术克服了盲法脑片膜片钳技术的缺陷,提高了神经元封接的成功率.通过对前庭内侧核神经元M受体通道电流性质的分析,进一步揭示毒蕈碱样胆碱能机制的兴奋性调节作用,为临床抗胆碱药物的应用提供新思路.     

硝普钠对豚鼠单离耳蜗外毛细胞全细胞电流的影响

目的研究并探讨硝普钠(sodium nitroprusside,SNP)对豚鼠耳蜗外毛细胞(outer hair cells,OHC)全细胞电流的影响及其作用机制.方法利用急性分离的OHC和特异性的离子通道阻断剂作为工具药,通过膜片钳电压钳记录技术观察了SNP对豚鼠耳蜗OHC全细胞电流的影响,结果①在以 40mV的指令电压刺激时,10-3mol/L的SNP抑制15.34±6.59%的细胞电流(n=5);②SNP对全细胞电流的抑制作用有电压依赖性,在刺激高于0mV时作用明显,10-2mol/L的SNP在 10mV时抑制率为4.97±1.74%,而在 40mV时的抑制率为33.82±1.61%;③SNP对全细胞电流的抑制呈量效关系,在浓度大于10-3mol/L时,抑制作用逐渐明显,10-1mol/L的SNP时接近达到最大抑制效应;④分离离子电流成分后,SNP仅对Ca2 电流有抑制作用.结论SNP对豚鼠耳蜗外毛细胞的全细胞电流的抑制作用,主要通过抑制细胞外Ca2 的内流,进而影响Ca2 依赖性K 通道而实现.     

听力学

20021291豚鼠耳蜗单离外毛细胞的外向整流钾电流/杨军…//临床耳鼻咽喉科杂志一2002,16(1)一27一30 目的:观察豚鼠耳蜗单离外毛细胞(OHC)的电生理特性,记录不同长度OHC的外向整流钾电流,分析区分外向整流钾电流所包含的通道电流成分,研究外向整流钾电流的动力学特征。方法:采用酶消化法及机械分离OHC。运动全细胞膜片钳技术,在电压钳下记录K 通道电流。结果:OHC的全细胞膜电容为(30.96士2.79)pF(n=29),零电流电位(30士2.1)mV(n=16),反转电位为(一51.67士1.84)mV(n一9)。不同长度OHC的外向整流钾电流存在系统差异,短OHC表现出大的钾…     

豚鼠耳蜗单离外毛细胞的外向整流钾电流

目的 :观察豚鼠耳蜗单离外毛细胞 (OHC)的电生理特性 ,记录不同长度OHC的外向整流钾电流 ,分析区分外向整流钾电流所包含的通道电流成分 ,研究外向整流钾电流的动力学特征。方法 :采用酶消化法及机械分离OHC。运用全细胞膜片钳技术 ,在电压钳下记录K+ 通道电流。结果 :OHC的全细胞膜电容为 (30 .96±2 .79) pF(n =2 9) ,零电流电位 (30± 2 .1)mV(n =16 ) ,反转电位为 (- 5 1.6 7± 1.84 )mV(n =9)。不同长度OHC的外向整流钾电流存在系统差异 ,短OHC表现出大的钾电导 ,长OHC则相反。 10 0 μmol/L的氯化镉 (Cd Cl2 )抑制了OHC外向整流钾电流的最大电流幅度的 6 0 % ,且改变了电流的动力学特征 ,对峰电流的影响明显大于稳态电流 (P<0 .0 1,n =5 ) ;1mmol/L的四氨基吡啶 (4 AP)抑制了最大电流幅度的 4 3% ,没有改变电流的动力学特征。外向整流钾电流的激活符合Boltzmann方程 ,V1/ 2 =(- 11.0 7± 0 .2 6 )mV ,S =(6 .6 2± 1.74 )mV(n=13)。结论 :外向整流钾电流包含有钙离子激活的钾离子电流、外向延迟整流钾电流和A型电流     

GABAB受体对位听神经脑干传人通路神经活动的影响

目的 本实验旨在探讨GABA能神经递质及GABAB受体对电刺激位听神经传入脑干通路兴奋性变化的影响.方法 使用出生后0～5 d的ddy/ddy小鼠制备脑干切片.脑片经电压敏感染料NK3041染色,电刺激与脑片相连的位听神经残端,使用16×16像素的硅光电二极管阵列测量膜电位变化引起的电压敏感染料吸光度的改变.观察GABA及GABAB受体拮抗剂2-Hydroxysaclofen(saclofen)对神经活动的影响,使用ARGUS-50/PDA软件分析实验数据.结果 多部位的光学记录方法显示了从位听神经到耳蜗核和前庭核兴奋性传导的时间-空间分布.神经活动可用电位或色彩的改变显示.每一个像素记录的电信号由快的峰电位样反应和慢反应组成.抑制性神经递质GABA可降低快的峰电位样反应及慢反应的幅度;GABAB受体拮抗剂saclofen能够部分逆转GABA的作用,随着saclofen(50μmol/L～100μmol/L)的浓度增加,在耳蜗核及小脑可引起去极化电位增强及后超极化电位.结论 电刺激位听神经在脑干传人通路可引起兴奋性神经活动,GABA及saclofen对诱发的神经活动有调节作用,提示GABA及GABAB受体在听觉传人通路和小脑担负重要的生理功能.     

硝普钠对豚鼠耳蜗外毛细胞全细胞钙电流作用的实验研究

目的　探讨一氧化氮供体———硝普钠 (sodiumnitroprusside ,SNP)对豚鼠单离耳蜗外毛细胞钙电流的影响及作用机制。方法　利用急性分离的豚鼠耳蜗外毛细胞 ,在全细胞膜片钳电压钳记录技术下 ,通过分离离子电流成分的方法 ,记录豚鼠耳蜗外毛细胞全细胞钙电流。结果　SNP对内向钙电流有抑制作用 ,在钳制电位为 -60mV ,刺激电压为 + 10mV的条件下 ,10mmol/L的SNP能抑制 (61 12± 1 99) %的内向钙电流 ( x±s ,n =5)。从 5～ 8个细胞得到的量效关系曲线中 ,其半数作用浓度为 1 9mmol/L ,最大抑制浓度为 10 0mmol/L ,斜率为 0 98。作用的机制为SNP可选择性地阻断外毛细胞膜上的L 型钙通道 (n =6)。结论　SNP作为一氧化氮的一种供体 ,能影响豚鼠耳蜗外毛细胞的生理功能 ,是通过阻断外毛细胞L 型钙通道电流的内流来实现的     

乙酰胆碱和三磷酸腺苷介导的豚鼠外毛细胞和Deiters细胞的离子电流

目的研究乙酰胆碱(acetylcholine, ACh)和三磷酸腺苷(adenosine triphosphate, ATP)介导的豚鼠耳蜗单离外毛细胞(outer hair cell, OHC)的离子电流.方法应用全细胞膜片钳技术,记录不同的钳制电压对ACh和ATP介导的离子电流的影响以及不同浓度的ACh和ATP分别引致的离子电流.结果 100 μmol/L ACh在钳制电压为-70 mV时引出一个内向电流和一个外向电流,-60 mV以上只引出了外向电流,其反转电位为(-80±5.61) mV(n=6). 100 μmol/L ATP在给予去极化钳制电压时,所引出的内向电流的幅度越来越小,在(3.2±0.23) mV(n=8)反转为外向电流.在单离的Deiters细胞上也记录出100 μmol/L ATP介导的离子电流.结论 ACh介导的外向电流是一种钾离子电流,ATP介导的内向电流是非选择性的阳离子电流,ACh和ATP对OHC的作用是电压依赖的.     

Study on voltage-sensitive current of spiral ganglion cells in mice organ of Corti culture]

OBJECTIVE: To investigate the property of voltage-sensitive current in cochlear spiral ganglion cells of the C57BL/10J mice, an inbred strain which develops early onset hearing loss. METHODS: Organotypic cultures of organ of Corti were prepared from neonatal mice 0-5 days of age. Whole-cell current and voltage clamp techniques were used to study Na+, K+ and Ca2+ currents of the spiral ganglion cells in culture. RESULTS: Cultures were maintained for 8-48 hours before use. Ganglion cells were identified first through their anatomical positions and finally through fast negative Na+ current. Spontaneous action potentials were recorded from some ganglion cells (4 out of 39). When present, spontaneous rates were around 20 spikes/sec, and might be as high as 135 spikes/sec. The mean resting potential was (-55 +/- 5) mV (n = 39). Under voltage clamp conditions, transient inward currents (negative) and outward (positive), steady-state voltage-dependent currents were recorded in normal HBSS. Rapid inward currents were totally blocked by 300 nM TTX applied locally to the culture. Inward currents recovered quickly after TTX wash out suggesting that the transient inward current was carried by Na+. The mean maximum amplitude of Na+ current was (-2.0 +/- 1.1) nA (n = 39) recorded in HBSS. Adding TEA (10 mmol/L) and 4-AP (0.15 mmol/L) to the bath solution or replacing K+ with Ca+ in the pipette solution partly blocked the sustained outward current. This suggests that the outward current was carried by K+. The mean maximum amplitude of K+ was (3.0 +/- 1.3) nA (n = 39) with 140 mM K+ in the pipette. Inward Ca2+ current was recorded in Ba2+ solution which mean peak amplitude was (-1.0 +/- 0.7) nA (n = 20). Ca2+ currents were reversibly blocked by 100 microM Cd2+. CONCLUSION: Whole cell recordings from spiral ganglion neurons can be obtained from organotypic cultures of the organ of Corti. Fast Na+ current, sustained K+ current and L-type Ca2+ current were recorded in the spiral ganglion cells cultured for 1-2 days. Whole cell recording showed that cochlea spiral ganglion cells can generate spontaneous action potential one day after birth and the firing rates could reach levels equal to those recorded in vivo.     

乙酰胆碱和三磷酸腺苷介导的豚鼠外毛细胞和Deiters细胞的离子电流

OBJECTIVE: To determine ACh- and ATP-induced currents in isolated outer hair cells of guinea pig cochlea, respectively. METHOD: The whole-cell patch-clamp technique was used to investigate potential and concentration dependence of ACh- and ATP-induced ion currents. RESULTS: ACh(100 mumol/L) induced an early inward current followed by a late outward current when the cells were voltage-clamped at -70 mV. Only outward current occurred when potential was over -60 mV and its reversal potential was (-80 +/- 5.61) mV(n = 6). When depolarization protocols were applied, amplitude of inward currents activated by ATP(100 mumol/L) decreased and reversed at (3.2 +/- 0.23) mV(n = 8). Ion currents activated by ATP (100 mumol/L) were also recorded from isolated Deiters' cells. CONCLUSION: ACh-induced outward current was carried by K+ and ATP-induced inward current was through non-selective cations channel. Effects of ACh and ATP on OHCs were voltage dependent.     

豚鼠Ⅱ型前庭毛细胞乙酰胆碱敏感性大电导钙依赖性钾通道与L型钙通道共存

目的 研究豚鼠Ⅱ型前庭毛细胞乙酰胆碱(acetylcholine,ACh)敏感性大电导钙依赖性钾通道(big conductance,calcium-dependent potassium channel,BK)激活过程中的钙离子内流机制.方法 健康杂色豚鼠52只,断头后取出前庭终器,经胶原酶IA消化后获取Ⅱ型前庭毛细胞.采用全细胞膜片钳技术检测新鲜单离的Ⅱ型前庭毛细胞ACh-敏感性BK电流对细胞外钙通道阻断剂和激动剂的敏感性.结果 ①细胞外ACh激活一缓慢持久的外向性电流,其反转电位为(-70.5±10.6)mV(-x±s,下同,n=10);-50 mV钳制电压下,100 μmol/L ACh激活电流的幅值为(267±106)pA(n=11).②ACh-敏感性钾电流对细胞外IBTX(iberiotoxin,200 nmol/L)敏感,而细胞外蜂毒明肽(apamin,1 μmol/L)对ACh-敏感性钾电流幅值无抑制作用.③ACh-敏感性BK对细胞外钙通道阻断剂NiCl2敏感,可被细胞外钙通道阻断剂CdCl2强力阻断.NiCl2和CdCl2对ACh-敏感性BK的半数抑制浓度分别为(135.5±18.5)μmol/L(n=7)和(23.4±2.6)μmol/L(n=7).④L型钙通道激动剂(-)-Bay-K 8644激活Ⅱ型前庭毛细胞产生一种与ACh-敏感性BK类似的外向性电流,并能被IBTX强力阻断.结论 Ⅱ型前庭毛细胞中ACh-敏感性BK与细胞膜L型钙通道共存,可能具有重要的生理学作用和意义.     

BK channels mediate the voltage-dependent outward current in type I spiral ligament fibrocytes

Recent experimental and clinical studies have provided considerable evidence to support the phenomenon of K(+) recycling in the mammalian cochlea. However, the precise cellular and molecular mechanisms underlying and regulating this process remain only partially understood. Here, we report that cultured type I spiral ligament fibrocytes (SLFs), a major component of the K(+) recycling pathway, have a dominant K(+) membrane conductance that is mediated by BK channels. The averaged half-maximal voltage-dependent membrane potential for the whole-cell currents was 70+/-1.2 mV at 1 nM intracellular free Ca(2+) and shifted to 38+/-0.2 mV at 20 microM intracellular free Ca(2+) (n=4-6). The reversal potential of whole-cell tail currents against different bath K(+) concentrations was 52 mV per decade (n=3-6). The sequence of relative ion permeability of the whole-cell conductance was K(+)>Rb(+)z.Gt;Cs(+)>Na(+) (n=5-17). The whole-cell currents were inhibited by extracellular tetraethylammonium and iberiotoxin (IbTx) with IC(50) values of 0.07 mM and 0.013 microM, respectively (n=3-7). The membrane potentials of type I SLFs measured with conventional zero-current whole-cell configuration were highly K(+)-selective and sensitive to IbTx (n=4-9). In addition, the BK channels in these cells exhibited voltage-dependent and incomplete inactivation properties and the recovery time was estimated to be approximately 6 s with repetitive voltage pulses from -70 to 80 mV (n=3). These data suggest that BK channels in type I SLFs play a major role in regulating the intracellular electrochemical gradient in the lateral wall syncytium responsible for facilitating the K(+) movement from perilymph to the stria vascularis.     

Voltage-dependent K(+) currents in spiral prominence epithelial cells of rat cochlea

It has been suggested that spiral prominence is associated with ion transport, but the characterization of ion channels has not been explored so far. We studied the electrical properties and ion conductances of the spiral prominence epithelial cells (SPECs), which are epithelial cells covering the luminal side of spiral prominence, in the upper turn of neonatal rat cochlea using a whole-cell variant patch clamp technique. The cell capacitance was 16.3+/-2.1 pF (n=33) and the resting membrane potential was -68. 9+/-2.5 mV (n=14) in perilymph-like bath solution. It was found that those SPECs possess a large voltage-activated, outwardly rectifying K(+) current and a small inwardly rectifying K(+) current. The outward K(+) current was activated by depolarizing pulses more positive than -30 mV, and sensitive to tetraethylammonium chloride (20 mM), 4-aminopyridine (10 mM), but not to Ba(2+) (0.5 mM). Tail current analysis revealed that it was primarily K(+)-selective. The time course of activation was well fitted by an exponential function raised to second power. The small inwardly rectifying K(+) current was sensitive to Ba(2+) (0.5 mM), and the Ba(2+)-sensitive current was K(+)-selective. In cell-attached or inside-out patch recordings, no discernible K(+) channel currents were found in the apical membrane of SPECs. Based on these results, we conclude that SPECs have two types of voltage-dependent K(+) currents, which are most likely located in the basolateral membrane.     

Actions of subtype-specific purinergic ligands on rat spiral ganglion neurons

In a previous study we showed that, in rat spiral ganglion neurons (SGNs), the adenosine 5'-triphosphate (ATP)-evoked currents were a combination of the activation of ionotropic receptors (the first fast current) and the activation of metabotropic receptors which secondarily opened non-selective cation channels. These two conductances imply the involvement of different receptor subtypes. In the present study, we tested three subtype-specific purinergic ligands: alpha,beta-methylene ATP (a;pha,beta-meATP) for P2X receptors, uridine 5'-triphosphate (UTP) for P2Y receptors and 2'-3'-O-(4-benzoylbenzoyl) ATP (Bz-ATP) for P2Z (P2X(7)) receptors. Application of 100 microM alpha,beta-meATP did not trigger any significant change in membrane conductance, while the SGNs were responsive to ATP. Pressure application of UTP (100 microM, 1 s) evoked an inward current averaging 344+/-169 pA at a holding potential of -50 mV. The conductance developed after a latency averaging 1.5+/-0.6 s, took 4-6 s to peak and reversed slowly within 15-30 s. The current-voltage curve reversed near 0 mV, suggesting a non-selective cation conductance, like the second component of the ATP conductance. Bz-ATP evoked an inward current which developed without latency, was sustained during ligand application and was rapidly inactivated at the end of application: the same characteristics as the first component of the ATP-evoked current. The Bz-ATP conductance reversed around -10 mV, indicating also a non-selective cation conductance. These results suggest that, in SGNs, ATP acts via two different receptor subtypes, ionotropic P2Z receptors and metabotropic P2Y receptors, and that these two receptor subtypes can assume different physiological roles.     

硝普钠对豚鼠耳蜗外毛细胞全细胞钙电流作用的实验研究

OBJECTIVE: To study the effects and mechanism of sodium nitroprusside (SNP), a donor of nitric oxide, on the calcium currents of isolated outer hair cells (OHCs) from the cochlear of guinea pigs. METHODS: Acute isolated outer hair cells of guinea pigs were performed, and the whole cell patch clamp recording techniques were used. The K+, Na+ ions were excepted to study effects of SNP on the calcium currents of outer hair cells. RESULTS: SNP inhibited the inward calcium currents of OHCs. Under the condition of holding at -60 mV and stimulation voltage as +10 mV, SNP (10 mmol/L) inhibited (61.12 +/- 1.99)% of the whole cell's calcium currents (n = 5). A dose-reaction response was obtained from 5-8 cells. The half inhibiting concentration was 1.9 mmol/L while the maximum inhibiting concentration was 100 mmol/L, but Hill coefficient was 0.98. SNP could selectively block the L-type calcium channels on outer hair cells (n = 6). CONCLUSION: As a donor of nitric oxide, SNP could affect the physiology function of outer hair cells by inhibition of the calcium currents by blocking the L-type calcium channels.     

大鼠耳蜗切片螺旋神经元的红外可视膜片钳技术

目的建立大鼠离体耳蜗切片技术，结合红外可视膜片钳技术探讨耳蜗螺旋神经元（spiral ganglion neuron，SGN）的电生理特性。方法0～2日龄、3～6日龄及7～14日龄的健康SD大鼠各10只，快速制作耳蜗切片，应用红外微分干涉相差技术，结合膜片钳记录，观察SGN的基本电生理特性，并分析影响耳蜗切片制作质量及膜片钳记录成功的因素。结果3～6日龄大鼠耳蜗切片的成功率最高，每只耳蜗可制备2～4张切片；保持部分颅骨与耳蜗的连接及耳蜗骨壳的完整是影响切片成功的关键，切片时蜗轴与刀片的位置及切片取材的时间也是影响切片质量和细胞活性的重要因素。红外可视膜片钳技术可准确找到状态良好的SGN，有助于对封接过程的判断。全细胞记录SGN静息膜电位平均为（-45．6±5．3）mV（x±s，n=52），可记录到Na^＋和K^＋电流。结论耳蜗切片技术能够较完整地保持耳蜗结构以及各种构成细胞的活性及其相互之间的联系，红外可视膜片钳技术具有实时、直视的特点，可操作性强，二者结合能为深入研究SGN的电生理特性及听觉传导机制提供良好的手段和平台。