目的探讨重复磁刺激(rMS)对体外培养大鼠神经干细胞(NSCs)增殖的作用机制。方法取新生3天内的Sprague-Dawley(SD)大鼠乳鼠双侧海马组织培养NSCs,通过cck-8试剂盒检测第2代NSCs的OD值绘制生长曲线图。再将第2代NSCs分为空白对照组和rMS组,rMS组刺激参数为频率10Hz,50%最大输出强度,每天200个脉冲,连续刺激3d。于rMS组最后1次干预1h后收集2组细胞,采用cck-8试剂盒检测其细胞增殖效应,同时用免疫印迹法检测c-fos蛋白和环磷酸腺苷反应元件结合蛋白(p-CREB)的表达量。结果第2代神经球经巢蛋白(nestin)免疫荧光染色证实为NSCs,生长曲线提示培养第3天时NSCs活性最佳。rMS干预后,rMS组cck-8的OD值为(0.309±0.043),与空白对照组的(0.256±0.045)比较,差异有统计学意义(P〈0.05);rMS干预后,rMS组的c-fos和p-CREB蛋白相对表达量分别与空白对照组比较,差异均有统计学意义(P〈0.01)。结论频率10Hz的rMS可促进NSCs的增殖,其作用机制可能与p-CREB和c-fos蛋白表达的增加有关。
Objective To study the mechanism of rats' neural stem cells (NSCs) proliferation in vitro after repetitive magnetic stimulation (rMS). Methods The bilateral hippocampus of neonatal Sprague-Dawley rats ( 〈3 d) was taken out to culture NSCs in vitro. The OD value was evaluated with Cell Counting Kit-8 (cck-8) and cell growth curve was generated. The NSCs cultured were divided into a control group and an rMS group, rMS (3 days, once per day) was applied on p2 NSCs at 10 Hz, 50% machine output and 200 pulses per day. One hour after the last rMS, the cck-8 was used to test the cell proliferation, and the western blotting was applied to detect the pro- tein expression of c-fos and p-CREB. Results The nestin fluorescent staining of p2 neurospheres was proved to be neural stem ceils. The growth curve indicated that their viability reached the peak on the third day. The OD value in the rMS group (0. 309 ± 0. 043) showed a significant difference (P 〈 0.05 ) after rMS compared with the control group (0.256 +± 0. 043). So did the c-fos and p-CREB protein expression between the two groups (P 〈 0.01 ). Conclusion The rMS at 10 Hz can promote rats' NSCs proliferation in vitro, which may be related to the increased expression of p-CREB and c-fos after rMS.