低氧后处理体外干预对缺氧缺血性脑损伤新生鼠的作用

Effect of hypoxic post-treatment on neonatal rats with hypoxic-ischemic brain damage

目的:探讨低氧后处理体外干预对缺氧缺血性脑损伤新生鼠的作用。方法:SD大鼠204只,按随机数字表法分为缺氧缺血性脑损伤组(HIBD组)、假手术组、8%O_2+92%N_2组(低氧A组)和15%O2+85%N2组(低氧B组),各51只。比较各组大鼠缺氧诱导因子(HIF)-1α表达水平和学习、记忆能力。结果:4组大鼠脑组织HIF-1α表达水平间差异有统计学意义(P<0.01),其中以低氧A组HIF-1α表达水平最高,其后依次为低氧B组、假手术组、HIBD组(P<0.01)。4组大鼠学习潜伏期、记忆潜伏期、学习错误次数和记忆错误次数间差异均有统计学意义(P<0.01),其中假手术组4项指标均明显优于其他3组(P<0.01),而低氧A、B组的记忆潜伏期和学习错误次数、记忆错误次数均少于HIBD组(P<0.05～P<0.01),低氧A组的学习潜伏期亦少于HIBD组(P<0.05)。结论:对缺氧缺血性脑损伤新生大鼠进行单次低氧后处理体外干预,能够有效促进HIF-1α表达,提升大鼠学习、记忆能力。

Objective： To investigate the effects of hypoxic post-treatment on neonatal rats with hypoxic-ischemic brain damage.Methods： Two hundred and four SD rats were randomly divided into the HIBD group,sham operation group,8% O_2 combined with 92%N_2 group（ hypoxic group A）,and 15% O_2 combined with 85% N_2 group（ hypoxic group B）（ 51 rats each group）. The levels of hypoxia inducible factor（ HIF）-1α and learning and memory abilities between four groups were compared. Results： The differences of the levels of HIF-1α in brain tissue between four groups were statistically significant（ P〈0. 01）,the level of HIF-1α expression in hypoxic group A was the highest,which gradually decreased in hypoxia group B,sham operation group,and HIBD group in turn. There were statistical significances in the study latency,memory latency,and number of learning errors and memory errors between four groups（ P〈0. 01）,the four indictors in sham operation group were significantly better than those in other three groups（ P〈0. 01）,the memory latency and number of learning errors in hypoxia group A and hypoxia group B were significantly less than those in HIBD group（ P〈0. 05 to P〈0. 01）,and the study latency in hypoxia group A was less than that in HIBD group（ P〈0. 05）. Conclusions： The hypoxic posttreatment in neonatal rats with hypoxic-ischemic brain damage can effectively promote the expression of HIF-1α,and enhance the learning and memory abilities of newborn rats.