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过氧化氢预处理对抗氧化应激诱导的PC12细胞凋亡

唐小卿, 陈静, 唐二虎, 冯鉴强, 陈培熹

中山大学中山医学院生理学教研室.广东,广州 510080

摘要

氧化应激可明显地诱导细胞凋亡。该研究旨在探讨H_(2)O_(2)预处理能否对H_(2)O_(2)诱导的PC12细胞凋亡产生保护作用及ATP敏感性K~(+)(ATP--sensitive potassium,K_(ATP))通道在其中的作用。采用PI染色流式细胞仪(flow cytometry,FCM)检测PC12细胞凋亡。结果表明,经10#mu#mol/L H_(2)O_(2)预处理90 min的PC12细胞,分别在20、30、50和100 #mu#mol/L H_(2)O_(2)作用24 h后,其细胞凋亡率明显下降,与未经H_(2)O_(2)预处理的PC12细胞相比,差异极显著({sl P}<0.01),表明H_(2)O_(2)预处理对H_(2)O_(2)诱导PC12细胞凋亡具有保护作用。用10#mu#mol/L的K_(ATP)通道激动剂pinacidil(Pin)可显著减少30和50 #mu#mol/L H_(2)O_(2)诱导的PC12细胞凋亡,10#mu#mol/L的K_(ATP)通道拮抗剂glybenclamide(Gly)则可显著地抑制甚至取消K_(ATP)通道激动剂Pin对H_(2)O_(2)诱导PC12细胞凋亡的保护作用,但并不影响H_(2)O_(2)预处理对H_(2)O_(2)诱导PC12细胞凋亡的保护作用;然而,当联合应用H_(2)O_(2)预处理与Pin时,对PC12细胞凋亡的保护作用明显大于各自的抗凋亡作用。提示K_(ATP)通道开放不仅对H_(2)O_(2)诱导PC12细胞凋亡具有保护作用,而且与H_(2)O_(2)预处理一起产生抗PC12细胞凋亡的协同作用,但K_(ATP)通道开放可能不参与H_(2)O_(2)预处理的适应性保护作用。

关键词： 预处理; H_(2)O_(2); PC12细胞; 凋亡; ATP-敏感性钾通道

Hydrogen peroxide preconditioning protects PC12 cells against apoptosis induced by oxidative stress

Tang Xiaoqing, Chen Jing, Tang Erhu, Feng Jianqiang, Chen Peixi

Department of Physiology,Zhongshan Medical College,Sun Yat-sen University.Guangzhou 510080,Guangdong

Abstract

Oxidative stress can induce significant cell death by apoptosis. We explore whether prior exposure to H_(2)O_(2)(H_(2)O_(2) preconditioning) protects PC12 cells against the apoptotic consequences of subsequent oxidative damages and what role the ATP sensitive potassium (K_(ATP)) channels play in the preconditioning protection. PC12 cells were preconditioned with 90 min exposure to H_(2)O_(2) at 10 #mu#mol/L, followed by 24-h recovery and subsequent exposures to different concentrations (20, 30, 50 and 100 #mu#mol/L) of H_(2)O_(2) for 24 h respectively. We used PI staining flow cytometry (FCM) to observe the apoptosis of PC12 cells. It was shown that 24-h exposures to H_(2)O_(2) at 20, 30, 50 and 100 #mu#mol/L respectively induced substantial cell apoptosis, which was greatly prevented in the preconditioning cells, indicating that H_(2)O_(2) preconditioning protected PC 12 cells against apoptosis induced by H_(2)O_(2). Administration of pinacidil (10 #mu#mol/L), an K_(ATP) channel activator, significantly attenuated the apoptosis of PC12 cells induced by H_(2)O_(2) at 30 and 50#mu#mol/L for 24 h respectively. Glybenclamide (10 #mu#mol/L), a K_(ATP) channel inhibitor, significantly suppressed or abolished the protective effects caused by the pinacidil but not by H_(2)O_(2) preconditioning. However, when both H_(2)O_(2) preconditioning and pinacidil were coapplied, their protection against the apoptosis of PC12 cells was much stronger than that of the individual one of them. These results suggest that H_(2)O_(2) preconditioning protects PC12 cells against apoptosis and that the activation of K_(ATP) channels is not involved in, but synergetically enhances adaptive protection of H_(2)O_(2) preconditioning.

Key words: preconditioning;Hydrogen peroxide;PC12 cells;;

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引用本文：

唐小卿, 陈静, 唐二虎, 冯鉴强, 陈培熹. 过氧化氢预处理对抗氧化应激诱导的PC12细胞凋亡[J]. 生理学报 2005; 57 (2): .

Tang Xiaoqing, Chen Jing, Tang Erhu, Feng Jianqiang, Chen Peixi. Hydrogen peroxide preconditioning protects PC12 cells against apoptosis induced by oxidative stress. Acta Physiol Sin 2005; 57 (2): (in Chinese with English abstract).