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目的 :分离豚鼠内耳活性良好的单离 Deiters细胞 ,观察其形态 ;探讨该细胞的基本电生理特性。方法 :采用酶孵育加机械分离法分离 Deiters细胞 ;利用膜电钳技术在全细胞模式下检测全细胞电容 ,记录在正常外液中的钾电流 ,零电流电位 ,反转电位 ,并根据相应公式计算离子通道 K+ 与 Na+ 的相对通透性比率 (PK/ PNa)及 K+平衡电位 (EK)。结果 :单离 Deiters细胞多呈逗点状 ,分为胞体 ,细柄和指突三部分 ,核靠近胞体中央 ,平均长度为(6 1.6± 2 0 ) μM(n=45 )。平均全细胞电容为 (2 7.5± 9.2 ) p F(n=2 8) ,零电流电位 (- 2 0± 1.8) m V(n=2 8) ,反转电位平均为 (- 6 4.3± 2 .9) m V(n =2 4) ,PK/ PNa=2 5 .4∶ 1,EK=- 84.2 m V。记录出 Deiters细胞在正常外液中的钾电流。结论 :根据 Deiters细胞的长度可以间接推断其在耳蜗中的位置 ,Deiters细胞离子通道具有高 K+ 选择性 ,其钾电流具有外向整流性和电压依赖性
OBJECTIVE: To isolate the detached Deiters cells with good activity in the inner ear of guinea pig and to observe its morphology. The basic electrophysiological properties of the cells were explored. Methods: Deiters cells were isolated by enzymatic incubation and mechanical separation. Whole cell capacitance was detected by membrane clamp technique in whole cell mode. Potassium currents, zero current potentials and reversal potentials were recorded in normal external fluid. According to the corresponding formula The relative permeability ratios (PK / PNa) and K + equilibrium potentials (EK) of ion channels K + and Na + were calculated. Results: The isolated Deiters cells were mostly comma-shaped. They were divided into three parts: cell body, fine stalk and finger. The nucleus was close to the center of the cell body and the average length was (6 1.6 ± 20) μM (n = 45). The mean total cell capacitance was (2 7.5 ± 9.2) p F (n = 2 8) and zero current potential (-2 0 ± 1.8) m V (n = 2 8) .9) m V (n = 2 4), PK / PNa = 2.54: 1, EK = -84.2 mV. The potassium current of Deiters cells in normal extracorporeal fluid was recorded. CONCLUSIONS: The location of Deiters cells in the cochlea can be indirectly deduced based on the length of Deiters cells. The Deiters ion channel has high K + selectivity and its potassium current has outward rectification and voltage dependence