新剂型神经生长因子联合丙戊酸促进大鼠坐骨神经损伤再生协同作用的实验研究

发布时间：2018-11-12 18:54

【摘要】：周围神经损伤实质上是神经元轴突的损伤，周围神经损伤后轴突逆向运输提供的神经营养因子骤减，导致部分神经元死亡，再生乏力。研究表明，靶组织合成的神经营养物质有利于损伤神经的再生与修复。神神经生长因子在神经损伤的再生过程中起着极其重要的营养和调控作用。但NGF存在无法通过血脑屏障、全身用药毒副作用大、水溶液中生物活性半衰期短等缺陷，基于此我们利用聚乙二醇/聚（γ-乙基-L-谷氨酸酯）（PEG-PELG）水凝胶担载NGF，制备出具有缓释能力的新剂型NGF。在体外试验证实NGF与VPA联合应用有促进PC12细胞分化的协同作用的基础上，采用Wistar大鼠坐骨神经损伤后创建硅胶管神经再生室的动物模型，将新剂型NGF(注射入神经再生室内)与VPA（口服）联合使用，观察神经损伤后轴突再生的数量、质量及神经电生理功能恢复变化情况。实验结果显示：1、B、C、D、E、F、G各组在D42时间点坐骨神经的肌电图检测呈现恢复期表现，通过神经再生室远端所产生的MUAP波形欠规则、离散，时限延长，各段波形不完全相同，经过神经再生室后均有明显AMP衰减，同时经过神经再生室的CV均有明显减慢，各组与A相比，均有统计学意义（P0.05）；其中D、E、F、G四组之间相比有差异，但无统计学意义（P0.05），，B、C两组之间相差不大无统计学意义（P0.05），D、E、F、G四组与B、C两组相比较AMP衰减率更小、CV增高明显存在统计学差异（P0.05）。2、观察各组再生神经轴突总面积及相对恢复率结果显示各组再生的神经均通过吻合口：A组神经轴突的髓鞘较厚，数目较多，平均直径大，其余各组光镜下观察见间质增多，再生的轴突髓鞘细小、分布分散，计算得出轴突总面积较空白组明显减少，轴突面积恢复率组间也有差异，与A组对比有明显统计学差异（P0.05）各组之间进行比较分析，其中E、F、G三组轴突总面积及轴突面积恢复率组间无统计学差异（P0.05），E、F、G三组轴突总面积及轴突面积恢复率分别均高于B、C、D三组具有统计学差异（P0.05）；D组轴突总面积及轴突面积恢复率高于B、C两组具有统计学差异（P0.05）；B、C两组轴突总面积及轴突面积恢复率组间相比无统计学差异（P0.05）。研究结论：硅胶管神经再生室内使用新剂型NGF可以促进神经再生，且可以表现出高剂量效果优于低剂量。低剂量新剂型NGF联合使用VPA效果与高剂量及高剂量联合VPA效果类似，具有协同作用。硅胶管神经再生室模型可以有效地进行促进神经再生药物效果的测定。
[Abstract]:Peripheral nerve injury is essentially neuronal axonal injury. After peripheral nerve injury, the neurotrophic factor provided by reverse axon transport decreases sharply, resulting in the death of some neurons and the lack of regeneration. The results showed that the neurotrophic substances synthesized from target tissues were beneficial to the regeneration and repair of injured nerves. Nerve growth factor (NGF) plays an important role in the regeneration of nerve injury. However, NGF can not pass through the blood-brain barrier, the toxicity and side effects of systemic medication are large, and the bioactivity half-life in aqueous solution is short. Therefore, we use polyethylene glycol / poly (纬 -ethyl-L-glutamate) (PEG-PELG) hydrogel to support NGF,. Preparation of a new formulation NGF. with slow release ability On the basis of in vitro experiment to prove that NGF and VPA can promote the differentiation of PC12 cells, an animal model of silicone tube nerve regeneration chamber was established by using Wistar rats after sciatic nerve injury. A new dosage form, NGF (injected into nerve regeneration chamber) and VPA (oral administration), were used to observe the quantity, quality and electrophysiological function of axon regeneration after nerve injury. The results showed that: 1 the electromyogram (EMG) of sciatic nerve in D42 time group showed convalescence, and the MUAP waveform produced at the distal end of nerve regeneration chamber was irregular, dispersed and prolonged. The waveforms of each segment were not exactly the same, there was obvious AMP attenuation after the nerve regeneration chamber, and the CV of the nerve regeneration chamber was significantly slower than that of the A group (P0.05). There was significant difference among the four groups, but there was no significant difference between the four groups (P0.05), but there was no significant difference between the two groups (P0.05), while there was no significant difference between the two groups (P0.05). The attenuation rate of AMP in group C was smaller than that in group C, and there was a significant difference in the increase of CV between group C and group C (P0.05). The total area and relative recovery rate of regenerated axons in each group were observed. The results showed that the regenerated nerves in each group passed through the anastomotic stoma: the myelin sheath of nerve axons in group A was thicker, the number of axons was larger, the average diameter was larger, and the interstitial mass was increased under light microscope in other groups. The regenerated axonal myelin sheath was small and scattered. The total area of axon was significantly reduced and the recovery rate of axon area was also different between the two groups. There was significant statistical difference between group A and group A (P0.05). There was no significant difference in the total area of axon and the recovery rate of axon area among the three groups (P0.05). The total area of axon and the recovery rate of the area of axon in the three groups were higher than those in the group B (P 0.05). Group D had statistical difference (P0.05); The total area of axon and the recovery rate of axon area in group D were higher than those in group B and C (P0.05), but there was no significant difference in total area of axon and recovery rate of axon area between group B and C (P0.05). Conclusion: the new dosage form of NGF can promote nerve regeneration, and the effect of high dose is better than that of low dose. The effect of low dose NGF combined with VPA is similar to that of high dose and high dose VPA, and has synergistic effect. The model of silicone tube nerve regeneration chamber can be used to determine the effect of drugs for promoting nerve regeneration.
【学位授予单位】：吉林大学
【学位级别】：博士
【学位授予年份】：2015
【分类号】：R651.3

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