工频磁场急性暴露对PC12细胞生长和凋亡的影响

Effects of Power Frequency Magnetic Fields Acute Exposure on Growth and Apoptosis of PC12 Cells

将体外传代培养的PC12细胞,经50 Hz、100μT的工频磁场暴露24 h。采用噻唑蓝比色法检测细胞增殖活力,流式细胞术检测细胞周期,吖啶橙/溴化乙锭免疫荧光双染色法检测细胞凋亡。结果表明:1)细胞增殖活力于磁场暴露终止后0 h明显下降(P<0.01);4 h未见著变;8 h(P<0.05)和12 h(P<0.01)显著升高。2)磁场暴露终止后0 h,G0/G1期细胞百分比显著增高(P<0.01),S期细胞百分比显著下降(P<0.05);6 h的G2/M期细胞百分比显著增高(P<0.05);12 h的G0/G1期细胞百分比明显下降(P<0.01),S期细胞百分比显著升高(P<0.05);24 h未见著变。3)磁场暴露期间,6 h细胞凋亡率未见显著改变,12、18和24 h凋亡明显增加,至暴露终止后4、8、12和24 h均显著升高,未见恢复。以上结果说明50 Hz、100μT的工频磁场急性暴露,可导致PC12细胞周期和增殖活力的改变,以及细胞凋亡增多。

PC12 cells were cultured in vitro, then exposed to 50 Hz and 100 μT extremely low frequency electromagnetic fields for 24 h. The proliferation activity, cell cycle and apoptosis was detected respectively by methyl thiazolyl tetrazolium colorimetry, flow cytometry and acddine orange/ethidium bromide, double label immunofluorescence. It was found that： 1） After exposure, proliferation activity was decreased at 0 h （P〈 0.01）, but increased at 8 h （P〈0.05） and 12 h （P〈0.01）, and there were no significant changes at 4 h. 2） After exposure, G0/G1 cells were increased （P〈0.01） and S cells were decreased （P〈0.05） at 0 h, GEM cells were increased （P〈0.05） at 6 h, G0/G1 cells were decreased（P〈0.01） and S cells were increased （P〈 0.05） at 12 h, there were no significant changes at 24 h. 3） The apoptotic rates were increased significantly at 12 h （P〈0.05）, 18 h （P〈0.01） and 24 h （P〈0.01） during exposure, and 6 h, 12 h, 18 h and 24 h after exposure （P〈0.01）. The results indicated that 50 Hz and 100 μT extremely low frequency electromagnetic fields exposure for 24 h can change the proliferation activity and cell cycle of PC12 cells and increase cell apoptosis.