C_6神经胶质瘤细胞的电压依赖性钾电流

VOLTAGE-DEPENDENT POTASSIUM CURRENTS IN RAT C_6 GLIOMA CELLS

本文用全细胞膜片箝方法对大鼠传代培养C6神经胶质瘤细胞（C6细胞）的电压依赖性K+电流进行了研究。实验共记录了97个细胞，膜电位均值（SD）为-47．5±9．4mV。有7％的C6细胞没有外向K+电流。具有外向K+电流的细胞，维持电压在-70mV时K+电流的激活阈值为-36．5±5．9mV。通过对尾电流的分析其逆转电位（SD）为-84．6±4．1mV，接近于K+平衡电位。在记录的细胞中所含K+电流的成分不同，约占总数60％的细胞，其K+电流包含呈暂态的快成分和呈稳态的慢成分。约占总数33％的细胞只具有慢成分。

n the present study, the properties of voltage-dependent K+ currents in culturedrat C6 glioma cells were investigated with the whole cell Patch-clamp recording technique. A total of 97 cells were recorded. The mean value of the membrane potentialwas- 47. 5±9. 4 mV. Seven Percent of the recorded C6 glioma cells did not show anyoutward potassium currents. The rest had outward K+ currents which could be activated at - 36. 5± 5. 9 mV from a holding potential of - 70 mV. Ananalysis of tail currents,showed the mean value of the reversal potential was - 84. 6± 4. 1 mV, close tothe K+ equilibrium potential. The K+ currents of 6O% of the recorded C6 cells consistedof both a fast and a slow component, while those of the 33% only with a slow component.