小鼠高原低氧环境暴露下脑内脂质过氧化损伤与高原脑水肿的关系

THE RELATIONSHIP BETWEEN INTRACEREBRAL LIPID PEROXIDATIVE INJURY AND BRAIN EDEMA IN MICE UNDER HIGH ALTITUDE HYPOXIC ENVIRONMENT

目的：观察高原不同海拔梯度下脑内脂质过氧化物的代谢变化，进一步探讨高原脑水肿的发生机理。方法：取三个不同海拔梯度下脑组织匀浆化学法测定脑内超氧化物歧化酶（ＳＯＤ）、丙二醛（ＭＤＡ）、谷胱甘肽过氧化物酶（ＧＳＨ－ＰＸ）和谷胱甘肽（ＧＳＨ）。结果：小鼠急进高海拔区后，随着海拔升高，ＳＯＤ含量逐渐升高，ＭＤＡ始终不变，但ＧＳＨ－ＰＸ和ＧＳＨ在进入中海拔区后增高，进入高海拔后ＧＳＨ－ＰＸ明显降低，而ＧＳＨ明显增高，差异均非常显著（Ｐ＜ ０．０１）。小鼠由低海拔区急进高海拔区后脑内ＳＯＤ水平随着时间延长呈增高趋势，ＣＸＨ—ＰＸ水平在进入高原第５ 天开始呈持续下降，ＧＳＨ水平从进入高原后的第７天开始上升，直到进入高原后的第１１ 天达到高峰，而后略有下降，但仍高于第７天的水平。实验结果同时表明，高海拔区不同时间暴露下脑组织含水量与脑内ＳＯＤ、ＧＳＨ和ＭＤＡ均呈正相关关系，与脑内ＧＳＨ－ＰＸ呈负相关关系。

Objective:To test the effects of level of intracerebral lipid peroxidation on brain injury under hypoxic environment to study the relationship cetween those effects and pathogenesis of high altitude brain edema.Methods:The level of SOD,MDA,GSH-PX and GSH of cerebral tissue homogenate were tested hy chemilminescence way at 1 517m,2 800m and 4 767m altitude separately.Results:Level of SOD increased gradually with highter altitude and prolonged duration when the mice exposed acutively to high altitude while unchange in MDA;level of GSH-PX and GSH increased at 2 800m altitude,and GSH-PX had a decrease on the 5th day postaltitude(4 767m)( P <0 01).The GSH was markability increased after the 7th day exposed high altitude( P< 0 01) and had a increment peaking on the 11th day followed with moderate decrease lastly.Furthermore,there was a positive correlation between watar content and level of SOD,GSH and MDA in brain,reversely,between water content and level of GSH-PX.Conclusions:The pathogenesis of high altitude cerebral edema could be associated with greater intercerebral lipid peroxodative respond under the condition of hypoxia.