常压高浓度氧致新生大鼠脑细胞凋亡及早期神经行为发育延迟  

Normobaric Hyperoxia Induced Brain Cell Apoptosis and Delayed Early Neurobehavioral Development in Newborn Rats

作　　者：李易娟[1] 刘美娜[1] 余慕雪[1] 庄思齐[1] 刘泳冬[2] 车丽红[2] 

机构地区：[1]中山大学附属第一医院儿科,广东广州510080 [2]中山大学附属第一医院病理科,广东广州510080

出　　处：《中山大学学报（医学科学版）》2009年第6期733-737,共5页Journal of Sun Yat-Sen University:Medical Sciences

基　　金：广东省医学科研基金(A2008162)

摘　　要：【目的】探讨常压高浓度氧对新生大鼠脑细胞凋亡、脑组织MBP(髓鞘碱性蛋白)表达和早期神经行为发育的影响。【方法】166只7日龄SD大鼠,随机分空气对照组和80%高氧模型组,新生鼠分别于开始吸氧后24、72 h被处死,TUNEL法观察不同高氧暴露时间大鼠脑组织细胞凋亡指数;高氧暴露72 h组在生后10、15 d,完成神经行为功能测试后,免疫组织化学染色观察脑组织MBP表达,空气组新生鼠处死日龄与高氧组相同。【结果】高氧2 h组脑细胞凋亡指数较高氧0h组(空气对照组)增加(P<0.01),随着吸氧时间的延长,细胞凋亡逐渐增多,以12～24 h组细胞凋亡最明显,72 h下降,但仍较0 h组增加(P<0.01)。高氧72 h组第10天、第15天MBP的表达较空气组低(137±5 vs.131±6,128±5 vs.122±5)(P<0.05)。高氧暴露72 h组新生大鼠听觉惊愕、负趋地性、前肢抓握反射、空中翻正的发育在一定日龄较空气对照组延迟(P<0.05)。【结论】常压高浓度氧可以引起新生大鼠脑细胞凋亡;抑制脑组织MBP的表达;导致新生大鼠神经行为发育延迟。[ Objective ] To evaluate the effects of hyperoxia on the brain cell apoptosis, expression of MBP （Myelin base protein） and the neurobehavioral performance. [Methods] A total of 166 7-day-old SD rats were randomly assigned into 2 groups： 80% hyperoxia group and normoxia group. Rat pups were killed in each group on the 24 h, 72 h after the exposure of oxygen for tunnel staining and apoptotic index （AI） was calculated. After exposing to oxygen for 72 h, tests for neurobehavioral toxicity were performed from dl0 to d15 and the pups were killed on d10, d15 for MBP stained with immunohistoehemical method. Normoxia group was used as normal control. [Results] The AI in 2h group was significantly higher than Oh group （normoxia group） （P 〈 0.01 ）. The AI of hyperoxia group was increased gradually with the prolongation of exposure to 80% oxygen and reached the highest level after exposure to oxygen for 12 - 24 h. After exposure to oxygen for 72 h, the AI decreased while still higher than 0 h group （P 〈 0.01 ）. The expressions of MBP in the brain of hyperoxia group were significantly lower than normoxia groups at d10 and d15 （137 ± 5 vs. 131 ± 6, 128±5 vs. 122±5）（P 〈 0.05）. The positive rates of acoustic startle, forelimb hanging, negative geotaxis, air righting were significantly lower than normoxia group at a certain age （P 〈 0.05）. [Conclusions] Normobaric hyperoxia could induce cell apoptosis in the newborn rat. Hyperoxia could decrease the expression of MBP to interfere the myelination of the developing brain. Hyperoxia could delay the neurobehavioral development of newborn rats.

关 键 词：高氧 大鼠 新生 脑细胞凋亡 神经行为 

分 类 号：R722.1[医药卫生—儿科]