急性重复缺氧对大鼠脑抗氧化活性和脂质过氧化反应的影响

Effect of acute repeated hypoxia on antioxidant activity and lipid peroxidation of rat brain

目的:研究急性重复低压缺氧对大鼠脑超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(glutathioneperoxidase,GSH-PX)活性和丙二醛含量的影响,为进一步研究预防、改善和保护高原人群和飞行人员在低氧环境中的脑功能或缺血脑功能的康复提供资料。方法:Wistar大鼠24只,随机分为地面组、5.0km组和7.0km组3组。将动物置于小动物低压舱内,模拟上升至5.0或7.0km高度,暴露1h。实验暴露1次/d,连续10d。最后一次缺氧刺激后,断头取脑,制备脑组织匀浆,并分离线粒体。采用试剂盒检测脑匀浆SOD活性和丙二醛含量,检测脑细胞胞质和线粒体GSH-PX活性。结果:急性重复缺氧后大鼠脑SOD犤(18.63±1.44),(21.53±1.90),(18.40±1.94)NU/mg犦和铜锌SOD犤(6.83±1.43),(10.04±1.90),(8.32±0.75)NU/mg犦活性,3组组间比较差异有非常显著性意义(P<0.01),F值分别为8.623和17.000。5.0km急性重复缺氧组大鼠脑总SOD和铜锌SOD活性非常显著高于地面组(P<0.01)。急性重复缺氧后大鼠脑匀浆和线粒体GSH-PX活性,3组组间比较差异有非常显著性意义(P<0.01),F值分别为13.935和7.611。7.0km急性重复缺氧组大鼠脑匀浆和线粒体GSH-PX活性非常显著高于地面组(P<0.01)。大鼠脑丙二醛含量各组间比较差异无显著性意义。结论:急性重复缺氧可提高大鼠脑抗氧?

AIM:To explore the effect of acute repeated hypobaric hypoxia on activities of superoxide dismutase(SOD) and glutathione peroxidase(GSH PX) and malondialdehyde(MDA) level of rat brain for prevention,improvement and protection of highland people and flyers against ischemic brain injury inducing by hypoxia. METHODS:Twenty four Wistar rats were randomly divided into ground group,5.0 km group and 7.0 km group.They were exposed 1h to the height of 5.0 km or 7.0 km in the little animal low pressure chamber.The experiment was done once daily for ten days continuously.The brain tissue homogenate of the rats were prepared after the last hypoxia exposure.The activities of SOD and MDA level of brain homogenate were measured by using test kit,and the activities of GSH PX in brain cell cytoplasm and mitochondria(Mt)in brain cells of rats were measured as well. RESULTS:The activities of total SOD[(18.63±1.44),(21.53±1.90),(18.40±1.94) NU/mg]and ZnCu SOD[(6.83±1.43),(10.04±1.90),(8.32±0.75) NU/mg] in cerebral homogenate of rats among the three groups were significantly different after acute repeated hypoxia(F=8.623, 17.000, P< 0.01).The activities of total SOD and ZnCu SOD in cerebral homogenate in the 5.0 km group were markedly higher than those of the ground group(P< 0.01).The activities of GSH PX in Mt and cerebral homogenate of rats following acute repeated hypoxia were significantly different among the three groups(F=13.935 and 7.611, P< 0.01).The activities of GSH PX in cerebral cytoplasm and in Mt increased significantly in the 7.0 km group as compared with the ground group(P< 0.01).No significant differences in the contents of MDA showed among the three groups. CONCLUSION:Acute repeated hypobaric hypoxia promotes the antioxidant activities of rat brain but has no effects on the production of lipid peroxidation of brain.It indicates that regular intermittent hypoxia training help body come into being and establish mechanism for coping with hypoxia,which may protect hypoxic brain function.