磁刺激对大鼠离体神经干细胞生长和分化的影响

目的 观察磁刺激对离体新生大鼠神经于细胞生长和分化的影响。方法 利用无血清培养技术，从新生大鼠脑室下区分离培养神经于细胞。将神经于细胞置于0．5Hz，刺激强度分别为0．48T(25％最大输出，B组)、0．95T(50％最大输出，c组)和1．44T(75％最大输出，D组)的条件下进行磁刺激干预，每天1次，每次30个脉冲，作用3d，同时设立对照组(A组)，用四甲基偶氮唑蓝(MTT)法检测细胞活性(0D值)，并用流式细胞技术检测神经于细胞分化情况。结果磁刺激各组神经于细胞在于预后24～48h0D值较A组稍低(P＜0．05)，至72h后可恢复至A组水平；流式结果显示磁刺激各组神经丝蛋白(NF)阳性细胞比例均高于A组，其中D组NF阳性神经元的比例最高(P＜0．05)。结论0．5Hz磁刺激对神经于细胞增殖有一过性的轻度抑制作用，有利于神经于细胞向神经元方向的分化。

Effects of magnetic stimulation on proliferation and differentiation of neural stem cells of neonatal rat in vitro

Objective To investigate the effects of magnetic stimulation (MS) on proliferation and differentiation of neonatal rat neural stem cell in vitro. Methods Neural stem cell derived from neonatal rat were exposed to MS (0.5Hz, 0.48T;0.5Hz, 0.95T;and 0.5Hz, 1.44T, respectively) once daily for 3 days. Thirty pulses of MS were delivered each time. The sham exposure controls were correspondingly established. Inverted phase contrast microscope was used to observe the cultured cell, MTT assay was applied to detect the activity of the cells as expressed by OD value, and flow cytometry was used to detect the results of cell differentiation. Results Although OD value of neural stem cell in all the MS groups were significantly less than that in control group 24 to 48 hours post MS, indicating a slightly restraint of the growth of neural stem cell, it reverted to the level of the control at 72 hours, the differences among the MS groups were not significant. The rates of neurofilament-positive neurons revealed by flow cytometry in MS groups were higher than that in control group, and which was the highest in MS of 0.5Hz, 1.44T ~(P<0.05) . Conclusion Magnetic stimulation slightly restrained the growth of neural stem cell and could promote of differentiation the rat neural stem cell into neuron-like cell in vitro.