中文摘要：

目的探讨不同压力和不同稳压时间下高压氧（HBO）对离体神经干细胞（NSCs）分化的影响,旨在找出HBO治疗的最佳压力与稳压时间。方法取出生3日内新生Sprague-Dawley大鼠的脑皮质组织,在含B27、bFGF和EGF的DMEM/F12培养基中悬浮培养NSCs。将传至2～3代的NSCs随机分为不做处理的对照组（CON）和HBO处理组。HBO处理组根据所用压力和稳压时间分为6组：NSCs分别给予1个绝对大气压（ATA）、2 ATA、3 ATA的HBO处理,每种压力再分别给予30和60 min两种稳压时间。HBO后继续培养24 h,7组细胞在同一时间行免疫荧光染色,荧光显微镜下观察NSCs分化为NSE阳性细胞的百分率。结果 NSCs分化为NSE阳性细胞的分化率从低到高依次为CON组（3.72±0.88%）,1ATA-30 min组（3.85±0.44%）,1ATA-60 min组（5.45±0.52%）,3ATA-30 min组（6.08±0.57%）,2ATA-30 min组（6.72±0.76%）,3ATA-60 min组（7.89±0.62%）,2ATA-60min（9.17±0.50%）;除1ATA-30 min组外,其余各HBO组与对照组比较,差异有统计学意义（P〈0.01）;同一压力下60min组与30min组之间的差异及2ATA-60 min组与其他各组之间的差异均有统计学意义（P〈0.01）。结论 2 ATA压力下稳压时间为60 min的HBO促进NSCs向神经元分化的作用最强。

英文摘要：

Objective To study the effect of hyperbaric oxygen（HBO） administered at different pressures and different exposure time on the differentiation of neural stem cells（NSCs） in vitro.Methods The cerebral cortices from newborn rats（0-3 days old） were sterilely collected,digested,and centrifuged.After removal of the supernatant,the cells were re-suspended with DMEM/F12 medium containing B27,bFGF and EGF.The NSCs of 2-3 passages were randomly divided into seven groups： a control（untreated） and 6 HBO treatment groups that NSCs were subjected to HBO treatment of different pressures（1,2 or 3 ATA） and different exposure time（30 or 60 minutes）.The differentiated NSCs were examined by neuron-specific enolase（NSE） immunocytochemistry 24 hrs later.Percentage of NSE positive cells differentiated from NSCs was assessed by fluorescent microscopy.Results The percentage of NSE positive cells differentiated from NSCs was the highest in the HBO 2ATA-60min group（9.17±0.50%）（P0.01）,followed by the HBO 3ATA-60min（7.89±0.62%）,HBO 2ATA-30min（6.72±0.76%）,HBO 3ATA-30min（6.08±0.57%）,HBO 1ATA-60min（5.45±0.52%）,HBO 1ATA-30min（3.85±0.44%） and control groups（3.72±0.88%）.In addition to the HBO 1ATA-30min group,the other HBO treatment groups had increased significantly percentage of NSE positive cells compared with the control group（P0.01）.Under the same pressure,the 60 min treatment groups had increased significantly percentage of NSE positive cells compared with the 30 min treatment groups（P0.01）.Conclusions HBO treatment（2 ATA,60 minutes） produces a best effect in the differentiation of NSCs into neurons.