神经营养因子3 壳聚糖支架诱导成年大鼠脑损伤后海马神经网络的形成

目的观察神经营养因子3(NT-3)壳聚糖支架诱导神经突触形成，修复成年大鼠创伤性脑损伤。方法60 只成年雄性Wistar 大鼠平均分为单纯损伤组、单纯壳聚糖支架组和NT-3 壳聚糖支架组，分别于术后3 d、7 d、14 d、28 d 和60 d，通过免疫组织化学方法检测损伤区神经再生。术后30 d 和60 d 应用神经示踪方法与免疫电镜技术观察损伤区内再生的神经突触。结果NT-3壳聚糖支架组海马损伤区内nestin+、微管蛋白β-tubulin-Ⅲ+、微管相关蛋白2 (MAP2)+神经细胞较单纯壳聚糖支架组和单纯损伤组明显增加(P<0.01)。NT-3 壳聚糖支架组在海马损伤区内观察到5-溴脱氧尿嘧啶(BrdU)/MAP2+双阳性新生神经元，并形成突触联系。结论NT-3 壳聚糖支架可激活脑损伤区神经前体细胞增殖，分化为成熟神经元并形成神经突触，参与脑神经网络的重建。

Neurotrophin-3 Chitosan Scaffolds Induced Hippocampal Neural Network Formation after Traumatic Brain Injury in Adult Rats

Objective To repair the traumatic brain injury in adult rats by inducing neural synapses formation with neurotrophin- 3 (NT-3) chitosan scaffolds. Methods 60 adult male Wistar rats were equally divided into lesion group, blank chitosan scaffolds group andNT-3 chitosan scaffolds group. The neural regeneration in the lesion area were observed through immunochemistry 3 days, 7 days, 14 days,28 days, 60 days after operation. Regenerated neural synapses involved the neural circuitry reconstruction in the lesion area were observed through neural tracing and immune electron microscopy 30 days and 60 days after operation. Results The nestin+, β-tubulin-Ⅲ+, microtubule associated protein 2 (MAP2)+ neural cells in hippocampal lesion area were significantly more in the NT-3 chitosan scaffolds group than in the other groups (P<0.01). Newborn neurons that express 5-bromouracil deoxyriboside (BrdU) and MAP2 were observed and formed synaptic connections in hippocampal damage zone in the NT-3 chitosan scaffolds group. Regenerated neural synapses involved the neural circuitry reconstruction in the lesion area. Conclusion NT-3 chitosan scaffolds activate the neural progenitor cells to proliferate and differentiate to mature neurons, which form neural synapses to involve the neural circuitry reconstruction.