极低频磁场对HepG2细胞内游离钙离子浓度的影响

目的　研究极低频电磁场是否影响细胞内钙离子浓度 ( [Ca2 +]i)。方法　Fura 2负载HepG2细胞分别在 1.5 5mT(均值 )、16Hz脉冲磁场处理 6 0min ,30 0mT、2Hz旋转磁场处理 5min后 ,用荧光光度计检测 [Ca2 +]i;实时检测 0 .9mT(有效值 )、16Hz正弦磁场对 [Ca2 +]i的影响。结果　在 1.5 5mT、16Hz脉冲磁场处理后 ,对照组和处理组R值 (F34 0nm　　 F380nm　　 )分别为 2 .4 5 19± 0 .2 378、2 .5 2 6 6± 0 .2 915 ,30 0mT、2Hz旋转磁场处理后R值分别为 1.36 5 0± 0 .0 6 2 6、1.36 0 2± 0 .0 771。 0 .9mT、16Hz正弦磁场处理下R值数据点拟合趋势线斜率比 [r(50 1～ 1 0 0 0 )　　　 r(0～ 50 0 )　　 ]分别为 1.12 13± 0 .4 5 5 9、1.0 72 7± 0 .1971,截距之比 [b(50 1～ 1 0 0 0 )　　　 b(0～ 50 0 )　　 ]分别为 0 .9912± 0 .0 0 98、0 .9979± 0 .0 0 6 0 ,差异均无显著性 (P >0 .0 5 )。结论　在本实验条件以及所采用的分析方法下未发现磁场对HepG2的 [Ca2 +]i产生影响

Effect of extremely low frequency magnetic fields on intracellular free calcium in HepG2 cells

OBJECTIVE: To study the effect of extremely low frequency magnetic fields on intracellular calcium concentration ([Ca(2+)]i). METHODS: Fura-2 loaded HepG2 cells were exposed to 1.55 mT (average value), 16 Hz pulsed magnetic fields for 60 min and to 300 mT, 2 Hz rotating magnetic fields for 5 min, and then [Ca(2+)]i was measured by fluorescence spectrophotometer. [Ca(2+)]i of HepG2 cells was also measured when they were exposed to 0.9 mT [root mean square (rms)], 16 Hz sinusoidal magnetic fields in real time. RESULTS: The R values (F(340) nm/F(380) nm) of the control and the exposed group were 2.4519 +/- 0.2378 and 2.5266 +/- 0.2915 respectively after HepG2 cells were exposed to 1.55 mT, 16 Hz magnetic fields, 1.365 0 +/- 0.0626 and 1.3602 +/- 0.0771 respectively to 300 mT, 2 Hz rotating magnetic fields. The ratios of the trendline slope [r((501 - 1,000)) / r((0 - 500))] from the data of R values were 1.1213 +/- 0.4559 and 1.0727 +/- 0.1971 respectively (P > 0.05), and the ratios of the intercept [b((501 - 1,000)) / b((0 - 500))] from the trendline were 0.9912 +/- 0.0098 and 0.9979 +/- 0.0060 (P > 0.05) when HepG2 cells were exposed to the 0.9 mT, 16 Hz sinusoidal magnetic fields. CONCLUSION: The effect of extremely low frequency magnetic fields on [Ca(2+)]i of HepG2 cells under the experimental condition has not been found.