模拟失重后大鼠海马齿状回神经发生的实验研究

观察模拟失重对大鼠海马齿状回神经发生的影响,为进一步阐明模拟失重对成年大鼠海马齿状回神经发生影响的规律及其相关生物学机制提供基本的实验依据。采用尾部悬吊法建立大鼠模拟失重模型,通过5-溴-2’-脱氧尿苷(5-bromo-2’-de-oxyuridine,BrdU)标记分裂细胞、微管相关蛋白(doublecortin,DCX)标记神经干细胞、神经元核蛋白(NeuN)标记神经元及胶质原纤维酸性蛋白(GFAP)标记神经胶质细胞的单、双重免疫组织化学染色方法比较尾部悬吊后7、14、28d模拟失重组大鼠与相应时间对照组大鼠之间海马齿状回神经前体细胞增殖、迁移和分化的情况。结果显示:模拟失重后7、14d尾部悬吊法模拟失重大鼠齿状回的BrdU免疫阳性细胞数目较相应对照组明显减少(P<0.01),而模拟失重后28d时两组大鼠齿状回BrdU免疫阳性细胞数目无显著差异(P>0.05)。本研究结果提示,模拟失重可抑制海马齿状回神经发生的水平。

The study of the hippocampal dentate gyrus neurogenesis after simulated weightlessness in the rat

In order to provide basic experimental evidence for further elucidating the characteristics of neurogenesis and the relative biologic mechanisms in dentate gyrus after simulated weightlessness,the effect of simulated weightlessness on neurogenesis in the adult rat hippocampal dentate gyrus was investigated.Weightlessness was simulated by tail suspension of rats.With bromodeoxyuridine(BrdU) to label dividing cells,doublecortin(DCX) to label neural stem cell,neuron-specific proteneural nuclei(NeuN) to label neuron and GFAP to label gliocyte,single-and double-immunohistochemical staining was adopted to compare the proliferation,migration and differentiation of neural precursor cells in the dentate gyrus between the intervention group and the control group at 7,14 and 28 d after simulated weightlessness.The results showed that the number of BrdU labeled cells in the dentate gyrus at 7 d and 14 d after simulated weightlessness was decreased as compared with controls(P<0.01),but at the 28 d after simulated weightlessness,there was no significant difference(P>0.05).These results suggest that neurogenesis in the dentate gyrus can be restrained after simulated weightlessness.