红藻氨酸诱导原代培养皮质神经元兴奋毒中p21变化及机制的研究

Alteration of p21 in Excitotoxicity of Primary Cultured Cortical Neurons Induced by Kainate and Its Mechanism

目的:探讨p21在红藻氨酸诱导的原代培养皮质神经元兴奋毒中的变化及可能机制。方法:原代培养大鼠皮质神经元经红藻氨酸(KA)处理24h后,激光共聚焦显微镜透射光下观察细胞损伤,应用Western blotting方法检测p21与p53蛋白表达的变化,用染色质免疫共沉淀(ChIP)-聚合酶链反应(PCR)方法检测p53与p21基因启动子上p53反应元件1结合情况。结果:KA处理后神经元明显损伤,部分细胞胞体缩小、变圆,突起变短、减少或消失,p21与p53蛋白表达上调,并且p53与p21基因启动子上的p53反应元件1结合增加。结论:在KA诱导的原代培养皮质神经元兴奋毒作用中p21蛋白表达上调,而p53直接参与了p21的激活。

Objective： To investigate the alteration of p21 in excitotoxicity of primary cultured cortical neurons induced by kainate （KA） and its mechanisms. Methods： After KA exposure for 24h, the primary cultured cortical neurons were observed under laser scanning confocal microscope with transmitted light, and the protein expressions of p21 and p53 were determined with Western blotting method, and the binding of p53 with p53 response element 1 in the promoter of p21 gene were detected with chromatin immunoprecipitation - polymerase chain reaction （ChlP-PCR） method. Results： KA exposure can induce neuronal injury, such as cell bodies shrinked and neurites shortened and diminished. In the KA induced neuronal injury, the protein expressions of p21 and p53 were up-regulated, and the binding of p53 with p53 response element 1 in p21 gene promoter increased. Conclusion： p21 protein is up-regulated in KA induced excitotoxicity of primary cultured cortical neurons and p53 is directly involved in activating p21.