高压氧对实验性脑梗死大鼠神经可塑性的影响

Influence of hyperbaric oxygen treatment on neural plasticity in experimental rats

目的:探讨高压氧对缺血性脑梗死后神经可塑性的影响及其作用机制。方法:选择4～5个月龄雄性SD大鼠90只,随机分为假手术组、模型组和高压氧组。建立大脑中动脉闭塞模型,在术后3 h对HBO组大鼠开始高压氧治疗。以横木行走试验进行神经功能评分,高压氧治疗后第1,2周采用免疫组织化学技术检测微管相关蛋白-2(microtubule-associated protein-2,MAP-2)和胶质纤维酸性蛋白(glial fibrillary acidic protein,GFAP)的分布,并用实时荧光定量PCR(real-time quantitative PCR,RT-PCR)检测梗死灶周Map-2 mRNA及GFAP mRNA表达量的变化。结果:脑梗死后第2周,大鼠平衡木试验显示高压氧组大鼠肢体功能评分较模型组低。免疫组织化学及荧光定量PCR结果均显示:高压氧治疗第1周,高压氧组梗死灶周围Map-2及Map-2 mRNA表达较假手术组及模型组显著增加,GFAP及GFAP mRNA表达较模型组明显减少但仍比假手术组高;高压氧治疗第2周,高压氧组梗死灶周围Map-2及Map-2 mRNA表达仍较假手术组及模型组高,GFAP及GFAP mRNA表达仍较模型组明显减少但比假手术组高。结论:缺血性脑梗死后,早期反复高压氧治疗可有效地改善肢体运动功能,并可通过促进Map-2以及抑制GFAP的表达促进缺血性脑梗死后神经的可塑性。

Objective To explore the influence of hyperbaric oxygen （HBO）treatment on neural plasticity and it＇ s mechanism in experimental rats with cerebral ischemia. Methods Ninetyhealthy male adult Sprague-Dawley rats （3 -4 month old ） were randomly divided into a pseudooperative group, a model group, and an HBO therapy group. The middle cerebral artery occlusion model was duplicated with suture methods, then we used beam walking test （BWT） to determine the motor skill of the rats and immunohistochemistry method to detect the distribution and location of microtubule-associated protein-2 （MAP-2） and glial fibrillary acidic protein （GFAP）. Quantitative real- time PCR was used to detect the expression of Map-2 mRNA and GFAP mRNA. Results Immunohistochemistry showed that the fluorescence gray scale value of Map-2 in the HBO group was the highest in 3 groups at 1 st week and 2nd week （ P〈 0.05 ）. The value of GFAP was lower than that of the model group but higher than that of the sham operated group （ P〈0.05 ）. Real-time fluores- cence-quantitative PCR indicated that the Map-2 mRNA of HBO group was the highest in 3 groups at 1 st week and 2 nd week （ P 〈0. 05 ） ; but the value of GFAP mRNA in the HBO group is lower than that of the model group, but higher than that of the sham operated group at 1 st week and 2 nd week （ P 〈 0.05 ）. Conclusion After cerebral infarction, giving hyperbaric oxygenation treatment can improve the limbs motor function, and hyperbaric oxygenation treatment can increase the expression of Map-2 and decrease the expression of GFAP, which promote neural plasticity.