Objective To discuss the impact of ADDLs on the activation of cytosolic ERK1/2 and possible molecu-lar mechanisms by which ADDLs affect synaptic plasticity, resulting in cognitive disorder.Methods The effects of AD-DLs on phosphorylated ERK1/2 within primary hippocampal neurons were determined by immunoblotting.Subcellular fractions were isolated to further explore the effect of ADDLs on the levels of p-ERK1/2within different parts of hipp -ocampal neurons.The effect of ADDLs on ERK1/2 binding to h3 Calponin was detected by co-immunoprecipitation. Results ADDLs reduced the amounts of p-ERK1/2 in a dose-dependent manner, while different effects were ob-served on p-ERK1/2 localized within cytoplasmic and nuclear compartments as exposure times went.ADDLs could re-markably weaken the quantities of cytoplasmic p-ERK1/2 after 1 hour of treatment.In contrast, the levels of nuclear p-ERK1/2 were significantly declined after treatment for 6 hours.According to co -immunoprecipitation results, the binding of ERK1/2 to h3 Calponin was dissociated 1 hour after ADDL administration when no obvious changes were seen as to the quantities of p-CREB in the nucleus.Conclusion ADDLs can suppress the activation of cytosolic ERK1/2 via blockage of ERK1/2 binding to h3 Calponin in hippocampal neurons at an early stage.%目的 探讨ADDLs对细胞质p-ERK1/2的影响,揭示ADDLs影响突触可塑性导致认知功能障碍的分子机制. 方法 采用体外培养的大鼠海马神经元. 免疫印迹方法观察ADDLs对p-ERK1 /2的影响,细胞组分分离方法探索ADDLs影响ERK1/2在神经元各部位活化的规律 ;免疫共沉淀的方法检测ERK1/2与h3 Calponin的结合以及ADDLs对两者结合的影响. 结果 ADDLs以时间依赖的方式降低了神经元中p-ERK1/2水平;AD-DLs对细胞质和细胞核部分ERK1/2的影响具有时序性,ADDLs作用1 h显著降低细胞质中p-ERK1 /2水平,作用6 h细胞核中的p-ERK1/2才显著降低;免疫共沉淀结果显示ADDLs作用1 h即可降低ERK1/2与h3 Calpo-nin的结合,而此时细胞核中p-CREB水平无显著变化. 结论 ADDLs作用早期首先通过阻断ERK1/2与h3 Calponin的结合影响细胞质ERK1 /2活化.
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