放射诱导的认知功能障碍是脑部肿瘤放射治疗最重要的临床问题之一，目前尚无有效的治疗方法。近年来的研究发现经颅骨移植神经干细胞能够解救放射诱导的认知功能障碍，而经血管移植神经干细胞尚未见研究。我们的前期实验发现，大鼠脑部照射后血脑屏障开放，粘附分子表达增加。因此我们假设经血管移植的神经干细胞能通过这种开放的血脑屏障进入脑实质并增加内源性神经发生，治疗放射诱导的认知功能障碍。为验证此假设，我们将：（1）观测经血管移植的神经干细胞是否进入脑实质；（2）观测抑制内皮细胞凋亡、封闭粘附分子表达对神经干细胞进入脑实质的影响以明确其进入脑实质的机制；（3）明确经血管移植神经干细胞对大鼠脑部照射后学习记忆能力的改善作用；（4）观察神经干细胞移植对内源性神经发生的影响。本课题将阐明脑部照射后经血管移植神经干细胞进入脑实质及治疗放射诱导认知功能障碍的机制，具有重要理论及实践意义。

Irradaition-induced cognitive dysfunction is one of the most important clinical issues for brain tumor , there is no effective treatment by now. Our preliminary studies showed that blood-brain barrier of rat would be destroyed and adhesion molecule would be upregulated after cranial irradiation. We assume that neural stem cells transplanted by vascular way would enter into brain parenchyma through the destroyed blood-brain barrier, and these grafted stem cells could ameliorate irradiation-induced cognitive dysfunction by derict substitute or addition of endogenous neurogenesis. To test this hypothesis, we would observe: (1) the nerual stem cells transplanted by vascular way could enter into brain parenchyma and the positional relationship between these stem cells and endothelial cells; (2)neural stem cells entering into brain parenchyma would be affected by inhibition of endothelial cells apoptosis or adhesion molecule upregulation; (3)spatial memory of rat could be rescued by neural stem cells transplantation;(4)grafted neural stem cells would affect endogenous neurogenesis、signaling molecules of administering neurogenesis and neuroinflammation; function of astrocytes originated from grafted neural stem cells. This issue is very important for theory and practice, which will clarify the mechanisms of grafted neural stem cells entering into brain parenchyma and ameliorating irradiation-induced cognitive dysfunction.