氟比洛芬酯对表达心脏SCN5A基因HEK293细胞钠电流的影响

目的:利用人胚肾293(HEK293)细胞表达心脏钠通道SCN5A基因并观察氟比洛芬酯(flurbiprofen axetil,FA)对钠通道的影响。方法:野生型SCN5A基因和SCN1B基因共表达于HEK293细胞,应用全细胞膜片钳记录使用FA(0.15μM)前后的钠电流。结果:转染效率约为70%,和使用FA前相比,用药后在每一指令电压上钠电流都减小;在测试电压为-40mV的条件下,钠电流峰值电流密度从(-159.74±63.80)pA/pF降至(-94.48±62.63)pA/pF(n=7,P=0.012);通道稳态激活半激活电压(V1/2)分别为(-51.66±7.69)mV和(-58.19±2.45)mV(n=7,P=0.048);稳态失活半激活电压(V1/2)分别为(-83.55±3.21)mV和(-85.25±4.78)mV(n=7,P=0.041);通道失活后恢复τ分别为(33.86±23.18)ms和(67.71±58.58)ms(n=7,P=0.048)。结论:FA可以减小各测试电压下的钠电流峰值(电压电流曲线向上漂移);加速通道的电压依赖性激活,促进通道的电压依赖性失活,失活后恢复变慢。

Effects of flurbiprofen axetil on the sodium channel expressed in human embryonic kidney cells

Objective：to investigate the features of the cardiac sodium channel （SCN5A） expressed in the human embryonic kidney （HEK） 293 cells,and to test its response to flurbiprofen axetil （FA）.Methods：Wild-type SCN5A gene was co-expressed with SCN1B gene in HEK293 ceils and the membrane currents were measured using a whole-cell patch clamp technique in the absence or presence of flurbiprofen axetil （0.15 μM）.Results：The transfection efficiency was about 70％.Compared with no medication of FA,the sodium currents at all the test potentials decreased after using FA; at the test potential of-40 mV,the peak sodium current decreased from （-159.74 ± 63.80） pA/pF to （-94.48 ± 62.63） pA/pF （n =7,P =0.012） ; the half-maximal voltage （V1/2） of the steady-state activation were （-51.66 ± 7.69） mV and （-58.19 ± 2.45） mV （n =7,P =0.048） ; V1/2 of the steady-state inactivation were （-83.55 ± 3.21） mV and （-85.25 ± 4.78） mV （n =7,P =0.041） ; channel recovery time constants were （33.86 ± 23.18） ms and （67.71 ± 58.58） ms （n =7,P =0.048）.Conclusion：FA decreased the peak sodium current at each test potential and up-shifted the voltage-current curve; quickened the voltage-dependent activation of the sodium channel and promoted inactivation of voltage-dependent of the sodium channel ; recovered slower after using FA.