摘要
Objective To investigate the toxicity of copper on MES23.5 dopaminergic cells and the probable mechanisms involved in this process. Methods MES23.5 dopaminergic cells were selected as our experimental model. [3-（4, 5-dimethylthiazol2-yl）-2, 5 diphenyltetrazolium bromide] （MTT） assay was used to detect the influence of copper on the cell viability. The semiquantitative reverse transcription polymerase chain reaction （RT-PCR）, Western blotting and the high performance liquid chromatography-electrochemical detection （HPLC-ECD） have been used to detect the tyrosine hydroxlase （TH） mRNA and protein expression and the dopamine content in MES23.5 cells. The flow cytometry have been used to detect the changes of mitochondrial transmembrane potential. Results 100 and 200 μmol/L copper had no effect on the MES23.5 cell viability, whereas 400 and 800 μmol/L of copper could decrease the cell viability （P 〈 0.01）. Treating cells with 200 μmol/L copper for 24 h decreased the TH mRNA expression, the TH expression and the dopamine content compared with the control （P 〈 0.01, P 〈 0.01, P 〈 0.05, respectively）. Besides, the mitochondrial transmembrane potential also decreased with the treatment of 200 μmol/L copper for 24 h （P 〈 0.01）. Condusion Copper could exert the toxic effects on MES23.5 dopaminergic cells and decrease the cell function. The dysfunction of mitochondria may be the mechanism of this toxicity effect.
目的探讨铜离子对MES23.5多巴胺能细胞的毒性作用及可能机制。方法用MTT法检测铜离子对细胞存活率的影响;用半定量逆转录聚合酶链反应(RT-PCR),Western blotting以及高效液相色谱电化学检测法(HPLC-ECD)检测细胞内酪氨酸羟化酶(tyrosine hydroxlase,TH)mRNA、蛋白的表达以及多巴胺含量的改变;用流式细胞仪检测线粒体跨膜电位的改变。结果100μmol/L和200μmol/L铜离子对细胞存活率没有影响,400μmol/L和800μmol/L铜离子可以造成细胞存活率降低(P<0.01)。200μmol/L铜离子孵育细胞24h,TH mRNA、蛋白表达量以及多巴胺含量较正常对照组降低(P<0.01,P<0.01,P<0.05)。200μmol/L铜离子孵育细胞24h,线粒体跨膜电位较正常对照组明显降低(P<0.01)。结论铜离子对MES23.5多巴胺能细胞具有毒性作用,降低细胞功能的表达,其机制可能与线粒体功能障碍有关。
