β淀粉样蛋白25～35急性给药和慢性孵育对神经元Ca2+非依赖性的K+电流作用的比较  

Comparison of the effects of acute administration and chronic exposure of β-amyloid-peptide 25-35 on the Ca2+-independent K+ currents in rat hippocampal and cerebral cortical neurons

作　　者：张鹏俊[1] 杨小荣[1] 董斌[1] 孙萍[1] 王永[2] 张策[1] 

机构地区：[1]山西医科大学生理学教研室,太原030001 [2]山西医科大学第二医院神经内科,太原030001

出　　处：《解剖学报》2009年第3期379-384,共6页Acta Anatomica Sinica

基　　金：国家自然科学基金资助项目(30572085)

摘　　要：目的探讨β-淀粉样蛋白25-35（Aβ25-35）急性给药和慢性孵育对神经元Ca^2＋非依赖性的K^＋电流作用的区别。方法急性分离大鼠海马及培养皮层神经元;Aβ25-35急性给药（3min）或慢性孵育（24h）;利用全细胞膜片钳技术记录Ca^2＋非依赖性的K^＋电流以及Calcein-AM法检测神经元活力。结果Aβ25-35急性给药使急性分离的海马神经元Ca^2＋非依赖性的K^＋电流幅度明显降低（n=11）,而慢性孵育则使培养的皮层神经元该电流幅度明显升高（n=11）。前者是Aβ25-35通过对K^＋通道直接的效应发挥其抑制作用,而后者可能主要是通过Aβ25-35上调通道蛋白,改变通道数量而发挥作用。结论不同的给药方式通过不同的机制对海马和皮层神经元的Ca^2＋非依赖性的K^＋电流产生不同的作用。Objective To study the different effects between the acute administration and chronic exposure of β-amyloidpeptide 25-35（Aβ25-35 ） on the Ca^2＋ -independent K^＋ currents in rat hippocampal and cerebral cortical neurons. Methods After different applications （acute administration and chronic exposure） of Aβ25-35 in rat hippocampal or cerebral cortical neurons, the Ca^2＋ -independent K^＋ currents were recorded by whole-cell patch clamp technique and the cell viability was detected by Calcein- AM staining. Results The amplitudes of the Ca^2＋ -independent K^＋ currents were significantly decreased by acute administration to Aβ25 - 35 in acute isolation of hippocampal neurons （ n = 11 ） while the amplitudes were markedly increased by chronic exposure to Aβ25-35 in cultured cerebral cortical neurons （n = 11 ）. Conclusion The different applications of Aβ25-35 on Ca^2＋ -independent K^＋ currents in hippocampal neurons and cerebral cortical neurons induced different results.

关 键 词：β-淀粉样肽25-35 电压激活的钾通道 离子电流 神经元 全细胞膜片钳技术 大鼠 

分 类 号：R338[医药卫生—人体生理学]