海马神经元损伤后PTEN表达水平与AMPA受体亚基表达定位变化的研究

目的 探讨海马神经元损伤过程中第10染色体同源丢失性磷酸酶张力蛋白基因(phosphatase and tensin homology deleted on chromosome ten,PTEN)表达水平的变化与谷氨酸(Glu)的α-氨基羟甲基恶唑丙酸(AMPA)受体亚基表达定位变化的关系.方法 选用新生SD大鼠原代培养海马神经元,建立神经元牵张损伤模型,采用Western blot和TUNEL染色检测神经元损伤各时相点PTEN表达的变化以及AMPA受体各亚基在细胞中的表达定位变化.结果 神经元牵张损伤后,PTEN的表达增加,细胞总蛋白中AMPA受体GluR1、GluR2、GluR3亚基的表达水平损伤前后差异无统计学意义,但细胞膜中的AMPA受体GluR2亚基在牵张损伤后明显降低.结论 海马神经元受到机械性牵张损伤后,细胞内PTEN水平与膜表面GluR2亚基表达变化相反.提示PTEN磷酸酶可能参与了AMPA受体中GluR2亚基的转运和再聚合过程.

Relationship of PTEN expression level with positioning of AMPA receptor subunit GluR2 in hippocampal neuron after stretch injury

Objective To explore the relationship of phosphatase and tensin homology deleted on chromosome ten ( PTEN ) expression with the positioning of AMPA recepter subunit GluR2 in hippocampal neuron after stretch injury. Methods The primary rat hippocampal neuron from neonate rats were cultured and the model of stretch injury established. Western blot and TUNEL staining were used to detect PTEN expression and the positioning of AMPA receptor subunit GluR2 in rat hippocampal neuron at different time intervals after stretch injury. Results The PTEN expression was increased obviously after stretch injury, while the expressions of AMPA receptors GluR1, GluR2 and GluR3 showed no evident differences at every time point. However, AMPA receptor subunit GluR2 located at cytomembrane was down-regulated obviously after stretch injury. Conclusion The intracellular PTEN expression and the expression of AMPA receptor subunit GluR2 located at cytomembrane are on the contrary, indicating that PTEN phosphatase may participate in the transport and reintegration process of AMPA receptor subunit GluR2 located at cytomembrane.