虎纹蜘蛛毒素-I对全脑缺血再灌注大鼠海马神经元Fas凋亡通路的抑制作用

Inhibitory Effects of Huwentoxin-I on the Fas Apoptosis Pathway of Hippocampal Neurons in Rats with Global Cerebral Ischemic Reperfusion Injury

目的:探讨虎纹蜘蛛毒素-I(HWTX-I)与由Fas分子启动的死亡信号转导通路之间的关系及可能的神经保护作用分子机制。方法:48只SD大鼠随机分为假手术组、生理盐水组及用药组三组,每组16只,采用改良的Pulsinelli"四血管阻断法"并结合蛛网膜下腔置管术构建全脑缺血再灌注损伤大鼠模型。免疫组织化学法检测海马组织CA1区Fas、FasL、FADD蛋白水平表达,RT-PCR法检测海马组织死亡信号转导通路相关因子Fas、FasL、FADD核酸水平表达。结果:免疫组化法检测结果显示,生理盐水组、用药组Fas、FasL和FADD蛋白表达高于假手术组,差异均有统计学意义(P<0.05,P<0.01),用药组Fas、FasL和FADD蛋白表达低于生理盐水组,差异均有统计学意义(P<0.05,P<0.01);RT-PCR检测结果显示,假手术组Fas、FasL、FADDmRNA表达低于生理盐水组和用药组,差异均有统计学意义(P<0.05,P<0.01),用药组Fas、FasL、FADDmRNA表达均低于生理盐水组,差异均有统计学意义(P<0.05,P<0.01)。结论:HWTX-I蛛网膜下腔用药对全脑缺血再灌注损伤大鼠海马组织具有一定的神经保护作用,其机制可能是通过抑制Fas分子启动的死亡信号转导通路激活而发挥作用。

Objective To observe the effects of Huwantoxin-I （HWTX-I） on the mRNA and protein expressions of the apoptosis-associated factors （Fas, FasL and FADD） in the hippoeampal tissues of rats with global cerebral ischemia reperfusion injury, and investigate its relation to the dead signal transduetion pathway. Methods SD rats were randomly divided into sham--operated group, saline group and HWTX--I group. Rat model of global cerebral isehemia reperfusion injury were established by Pulsinelli ＂4--vessel occlusion＂ combined with tube placement in subaraehnoid space. The protein expressions of Fas, FasL and FADD in hippoeampal CA1 region were detected with immunohistoehemieal assay; the changes of the mRNA expressions of the dead signal transduction pathway related factors in hippocampal tissue were detected with reverse transcription--polymerase chain reaction （RT--PCR）. Results HWTX--I significantly depressed the protein expressions of Fas, FADD in the hippoeampal CA1 region of rats with global cerebral ischemia reperfusion injury （P〈0.05） and the protein expressions of FasL （P〈0.01）. HWTX--I remarkably reduced the mRNA expressions of Fas, FasL （P〈0.05） and the mRNA expressions of FADD （P〈0.01） in hippoeampal tissue of rats with global cerebral isehemia reper- fusion injury. Conclusion The administration of HWTX--I into subaraehnoid space revealed certain protective effect on the hippoeampal tissue of SD rats after global cerebral isehemia reperfusion, probably through the restraining the dead signal transduetion pathway.