三氧化二砷对大鼠皮质神经元迁移的影响及其机制

Effect of arsenic trioxide on cortical neuronal migration of rats and its potential mechanism

目的 通过构建大鼠乳鼠神经元原代细胞培养模型，探讨三氧化二砷（Aszos）对神经元迁移的影响及其机制。方法取sD大鼠新生乳鼠脑组织进行皮质神经元原代培养，建立细胞培养模型。实验分为4组：正常对照组、1μmol／LAs203组、10μmol／LAs203组和20μmol／LAs203组。加入不同浓度As203培养24h，采用Boyden趋化小室检测各组神经元的迁移情况，免疫荧光激光共聚焦显微镜观察肌动蛋白的结构。结果正常对照组神经元分布规律；1μmol／LAs203组、10μmol／LAs203组和20μmol／LAs203组神经元生长稀疏，杂乱分布，其中20μmol／LAs203组最为明显。正常对照组、1μmol／LAs203组、10μmol／LAs203组和20μmol／LAS，0，组神经元在相同单位时间内迁移的平均细胞数分别为64．6±4．3、63．0±7．0、54．8±3．6、21．6±3．9。组间比较差异有统计学意义（F=49．31，P〈0．01）。共聚焦显微镜下观察到正常对照组和1μmol／LAs，0，组神经元内的肌动蛋白呈纤维状条带分布，10μmol／LAs203组和20μmol／LAs203组神经元肌动蛋白断裂、散在分布。结论As：0。可以干扰神经元的迁移，与As：0，的浓度有关，肌动蛋白的结构破坏可能是其潜在机制。

Objective To explore the effect of arsenic trioxide （ As2 O3 ） on the migration of neurons and the potential mechanism through the establishment of primary neuron culture from the brains of neonatal rats. Methods Brain tissues were selected from SD neonatal rats for primary neuron calture. The cells were divided into 4 groups based on the addition of As2O3 ：normal control group, 1 μmol/L As2O3 group, 10 μmol/L As2O3 group and 20μ mol/L As2O3 group. The primary neurons were treated with different concentrations of As2O3 and cultured for 24 hours. Boyden chamber assay was used to detect the effect of As2O3 on neuronal migration. Immunofluorescence laser confocal microscope was used to observe the structure of actin. Results In the control group,the cultured neurons showed a regular pattern of distribution. In the 3 groups treated with As2 O3, the distribution of neurons was loose and disordered, which was most obvious in the 20 μmol/L As2 O3 group. The results showed that the higher concentration of As2O3 , more difficult it was for the neurons to survive. The number of neuronal migration was 64.6 ±4.3 for normal control group,63.0 ±7.0 for 1μmol/L As2O3 group,54.8 ± 3.6 for 1. μmol/L As2O3 group, and 21.6± 3.9 for 20mol/L As2O3 group. The results showed that As2O3 might inhibit the migration of primary neurons in a dose - dependent manner （ F = 49.31, P 〈0. 001 ）. The normal actin skeleton was destroyed under the laser confocal microscope in 10 μmol/L As2O3 group and 2O μmol/L As2O3 group, while they remained unaffected in normal control group and 1μmol/L As2O2 group. Conclusion As2O3 exposure can reduce the neuron migration in a dose-independent manner probably through disrupting the organization of acting cytoskeleton.