急性低压低氧环境下富氧干预对大鼠认知功能及海马CA1区形态学的影响

Effects of Oxygen Enrichment Intervention on Cognitive Function and Morphology of Hippocampus CA1 Region of Rats Under Acute Hypobaric Hypoxia Environment

目的探索在模拟急性低压低氧环境下采用便携式膜法氧气机进行富氧干预对大鼠认知功能及海马CA1区形态学的影响,为氧气机的应用评价提供理论依据。方法 30只雄性SD大鼠随机分为平原对照组(NC组)、低压低氧组(LO组)、低压富氧组(HO组),每组10只。采用小型动物实验用环境模拟舱模拟海拔6000 m高原低压低氧环境,LO组和HO组暴露于低压低氧环境3 d,HO组每天在昼间富氧12 h,NC组暴露于空气中。Morris水迷宫检测大鼠认知功能,光镜观察海马CA1区HE染色。结果 LO组大鼠穿越平台次数显著低于NC组(P<0.05)和HO组(P<0.05),HO组和NC组间差异无统计学意义(P>0.05)。LO组变性锥体细胞数明显多于NC组(P<0.05)和HO组(P<0.05),HO组海马锥体细胞结构损伤显著减轻,变性锥体细胞数与NC组比较无统计学差异(P>0.05)。结论模拟海拔6000 m急性低压低氧环境下采用便携式膜法氧气机进行富氧干预能有效减轻海马损伤,显著提高大鼠的认知功能。

Objective To explore the effects of oxygen enrichment intervention by portable membrane oxygen machine on cognitive function and morphology of hippocampus CA1region of rats under a simulated acute hypobaric hypoxia environment,and provide a theoretical basis for the application and evaluation of oxygen machine.Methods Thirty male SD rats were randomly divided into three groups:NC group,LO group and HO group.A simulated altitude of6000m acute hypobaric hypoxia environment was provided by the environment simulation cabin for small animal experiment.SD rats in the LO and HO groups were exposed to hypobaric hypoxia environment for3days,whereas SD rats in the HO group were enriched with oxygen for12h during the daytime,and SD rats in the NC group were exposed to air.The cognitive function of rats was determined by Morris water maze test,and HE staining in hippocampus CA1region was observed under light microscope.Results Compared with rats in the NC group and the HO group,rats in the LO group presented significantly decreased number of platform crossings(P<0.05),while there was no significant difference between the NC group and the HO group.The degenerative pyramidal cells in the LO group were significantly higher than that in both the NC and the HO groups(P<0.05).The structural damage of the hippocampal pyramidal cells in the HO group was significantly alleviated relative to that in the LO group.There was no significant difference in the number of degenerative pyramidal cells between the HO and NC groups(P>0.05).Conclusion Under the simulated altitude of6000m acute hypobaric hypoxia environment,oxygen enrichment intervention using a portable membrane oxygen oxygen machine can effectively alleviate hippocampal damage and significantly improve the cognitive function of rats.