荧光蛋白转基因小鼠神经干细胞移植对脑损伤大鼠认知功能及神经生长因子表达的影响

目的 建立大鼠自由落体颅脑损伤动物模型,并探讨静脉内注射神经干细胞(NSC)对大鼠脑损伤后神经功能恢复及NGF表达的影响.方法 采用仿Feeney自由落体脑损伤装置,用50 g的击锤沿导引杆从30cm高处自由坠落冲击撞杆,造成大鼠右顶叶皮质运动感觉区脑挫裂伤,24h后通过大鼠尾静脉移植GFP转基因小鼠NSC,1周后行神经功能评分并行NGF免疫组织化学染色.结果 NSC移植后1周,移植细胞在损伤区域聚集;NSC移植组认知功能评分和NGF阳性细胞数[(226±27)分,(23±4)个]与单纯脑损伤组[(300±36)分,(15±3)个]比较差异有显著性(P＜0.05).结论 NSC移植明显促进脑损伤大鼠认知功能恢复,NGF可能是修复机制中的一个重要分子.

Effects of neural stem cell transplantation from GFP transgenic mice on rat neurocognitive function and NGF expression after brain trauma

Objective To establish contusion brain injury model in rats, and investigate the efficacy of intravenous administration of neural stem cells(NSC) on posttraumatic neurocognitive function recovery and NGF expression in rats. Methods Cerebral contusion model in motor-sensory cortex of the right parietal cortex in rat was established by a 50 g-weight hammer falling respectively from 30 cm height along guide stick to impact collision pole by improved trauma device for model of contusion brain injury based on Feeney method. And the NSC isolated from GFP transgenic mice were injected intravenously via the tail vein 24 h after the brain trauma, and 1 week later neurocognitive function scores and NGF immunostaining were performed to explore the efficacy of NSC transplant. Results The NSCs from the GFP transgenic mice gathered at the injury site 1 weeks after transplants.Neurocognitive function scores and NGF-positive cells measurement(226 ±27,23 ±4 ) in the treatment group revealed significant increase than in the brain trauma group(300 ±36;15 ±3 )(P＜0.05). Conclusion The intravenous NSC injection in rats can survive and migrate to the injured brain region and promote the post-injury neurocognitive function restoration. The increase of NGF expression may underline one of most important mechanisms in NSC treatment' s rats after brain injury.