Rae J L, Rae J S
Department of Physiology, Mayo Foundation, Rochester, Minnesota 55905.
Invest Ophthalmol Vis Sci. 1992 Jun;33(7):2262-8.
Perforated patch techniques were used to measure whole-cell ionic currents in freshly dissociated human lens epithelial cells that had not been subjected to culture media or serum. With a 150 mmol/l K+ internal solution, the cells had resting voltages of -27.4 +/- 4.7 mV (mean +/- standard deviation [SD]) and capacitances of 10.4 +/- 2.8 pF (mean +/- SD). The input resistance of the cells was 1.6 +/- 0.7 G omega (mean +/- SD) at large negative voltages. A delayed outwardly rectifying K+ current was found in most cells studied. Current magnitudes of 1-2 nA at +80 mV were common. The current had selectivities, activation time constants, deactivation time constants, open probability versus voltage relationships, and inactivations similar to those of the delayed rectifying K+ current found in many cell types and studied previously in cultured human lens epithelium. These results verify the existence, at high density, of these currents in noncultured human epithelial cells.
采用穿孔膜片钳技术，对未接触过培养基或血清的新鲜解离的人晶状体上皮细胞的全细胞离子电流进行测量。在胞内液为150 mmol/l K+ 时，细胞的静息电压为-27.4±4.7 mV（平均值±标准差[SD]），电容为10.4±2.8 pF（平均值±SD）。在大的负电压下，细胞的输入电阻为1.6±0.7 GΩ（平均值±SD）。在大多数所研究的细胞中发现了一种延迟外向整流性K+电流。在+80 mV时电流大小为1 - 2 nA很常见。该电流具有选择性、激活时间常数、失活时间常数、开放概率与电压的关系以及失活特性，这些特性与在许多细胞类型中发现的延迟整流性K+电流类似，且之前在培养的人晶状体上皮细胞中也有研究。这些结果证实了在未培养的人上皮细胞中高密度存在这些电流。
