脉冲磁场对应激大鼠海马神经干细胞增殖的影响

Effect of Pulsed Current Magnetic Fields on Neural Stem Cell Proliferation in Hippocampus of Stressed Rat

建立大鼠束缚应激模型及脉冲磁场环境,观察应激大鼠在脉冲磁场环境中海马神经干细胞数及增殖变化.实验设对照、应激、磁场、应激磁场4个组,应用免疫组织化学法观察和计算各组海马巢蛋白(Nestin)和溴化脱氧核糖尿嘧啶(BrdU)的阳性细胞数.研究结果显示,Nestin在各组海马CA1和CA2区表达,BrdU在海马齿状回表达.实验各组Nestin和BrdU的阳性细胞比对照组明显增加,应激磁场组增加更显著,而磁场组和应激磁场组则无明显差异.这表明应激能引起大鼠海马神经干细胞内源性增殖,脉冲磁场能显著提高应激大鼠海马神经干细胞的增殖反应,提示在应激脑损伤的基础上,脉冲磁场作为外源性物理因素能刺激神经干细胞增殖,并可能修复受损神经元.

The restrained stress model of female rats in pulsed current magnetic fields （PCMFs） was established to observe the effects of PCMFs on neural stem cell quantity and proliferation in hippocampus of stressed female rats. Four groups, control, stress, PCMFs, and PCMFs ＋ stress, were divided into, and the quantities of nestin-positive cells and BrdU-positive cells were contrastively counted and determined in different groups with the method of immunohistochemistry. It is found that the nestin-positive cells are assembled in hippocampal CA1 and CA2 regions for all groups, the BrdU-postitive cells were assembled in hippocampal dentate gyrus（DG）, and the expression of nestin- and BrdU-positive cells in each of the other three groups is stronger than that in control group, especially in PCMFs ＋stress group, but no significant difference between PCMFs group and PCMFs ＋ stress group. It is suggested that stress is capable of increasing inner neural stem cell proliferation in hippocampus of female rats, while PCMFs, as outer physical factor, enable to stimulate neural stem cell proliferation and reform the damaged neuron.