双氧水预处理诱导脑缺血耐受的实验研究

Experimental Study of Ischemic Tolerance Induced by Hydrogen Peroxide Pretreatment in Rats

目的:探讨双氧水预处理对大鼠局灶性脑缺血(FCI)损伤的保护作用及钠离子通道在双氧水预处理中的作用。方法:40只雄性SD大鼠采用线栓法制作FCI模型,随机分为A组,单纯缺血再灌注组;B组,缺血前24 h用微量泵1 h内缓慢静脉泵入3%的双氧水1 ml;C组,缺血前24 h给予利多卡因(5 mg/kg,ip);D组,利多卡因加双氧水预处理组,每组10只。于再灌注后24 h行脑功能障碍评分,并处死测量脑梗死容积。结果:B组脑功能障碍评分和脑梗死容积显著低于A组(P<0.05);C、D组与A组比较差异无显著性意义。结论:双氧水预处理对大鼠FCI损伤有明显的保护作用,但此作用可被利多卡因阻断,提示钠离子通道参与此效应的形成机制。

Objective： To study the effects of hydrogen peroxide pretreatment on focal cerebral ischemia（FCI） in rats and investigate the effects of lidocaine on the ischemic tolerance induced by hydrogen peroxide pretreatment. Methods： Forty SD rats with the FCI model were randomly allocated to 4 groups： group A, single ischemia and reperfusion; group B, animals receiving 3% hydrogen peroxide 1 ml by a perfusor; group C, animals intraperitoneally injected with 5 mg/kg lidocaine; group D, animals receiving 5 mg/kg lidocaine before hydrogen peroxide pretreatment. Neurologic deficit scores were assessed at 24 h after reperfusion. Then all the rats were killed and the infarct volume measured. Results： The neurologic deficit scores and infarct volumes in group B were decreased as compared with those in group A （P〈0.05）, while there was no significant difference among group A, C and D. Conclusion： Hydrogen peroxide pretreatment can induce ischemic tolerance in FCI rats. This effect can be blocked by lidocaine, suggesting the sodium channel is involved in the formation of this mechanism.