早产儿脑损伤的发生机制日益受到关注。我们前期的研究发现，缺氧缺血大鼠脑组织中一些miRNA表达明显下调，利用芯片技术对缺氧缺血后脑组织进行分析，筛选出差异表达明显的miR-182和miR-200b。根据预测结果，此两种miRNA可能通过Fbxw11和Rac1基因参与Wnt信号通路，但其对早产儿脑损伤结局的影响及具体机制还不清楚。因此，拟利用离体脑片和在体动物的缺氧缺血模型，将miR-200b和miR-182全长及反向序列转染到脑组织中造成过表达和低表达，分别进行：RNA和蛋白水平分析此两种miRNA对Fbxw11和Rac1基因、Wnt信号通路、不同发育阶段少突胶质细胞、髓鞘及轴突损伤、修复的影响；从电镜水平分析此两种miRNA对于轴突、髓鞘形态及数量的影响；从神经行为学角度分析它们对于动物的认知、记忆及运动等方面的影响。从而为早产儿脑损伤后脑功能的康复治疗寻找新的治疗靶点，并提供实验依据。

The mechanisms of preterm brain injury has been increasingly paid more attention.Our previous studies showed the expression of some miRNA was significantly downregulated in hypoxic-ischemic brain tissue ,found two significant differential expression miR-182 and miR-200b by analyzing hypoxic-ischemic brain tissue with miRNA chip. Based on the findings, we hypothesized that the two miRNA involved in Wnt signal passway through Fbxw11 and Rac1 gene. However, the effection on preterm brain injury and the mechanism remains unclear.We intend to bulit the hypoxic-ischemic animal model , transfect the full length and reverse sequence of miR-200b and miR-182 to brain ,develop over expression and low expression,observe the effection of the two miRNA on Fbxw11 and Rac1 gene, Wnt signal passway , oligodendroglia of different development stage ,injury and repair of myelin sheath and axon from the level of RNA and protein; on the shape and number of axons ,myelin sheath from the level of electron microscope; on the recognition ,memory and movement of animal from the point of neuroethology. The study findings will help to find new targets of rehabilitative treatment after preterm brain injury and provide experiment basis to these.