Retrograde neuronal cell death in the facial nucleus after axotomy in the brainstem -alteration of MMPs expression, cell migration and axonal regrowth-

本研究的目的是建立一个模型，以探讨各种病变的面神经切开术后面神经核逆行性神经元细胞死亡的未知机制。此外，研究了自体周围神经组织的神经保护作用和MMPs表达的改变。模型包括脑干损伤模型；立体横切脑干面神经束膝，建立对照损伤模型；面神经束远端损伤模型，面神经束远端无横断；面神经在茎突孔处切开，近端损伤模型；面神经在茎突孔处断裂，导致远端损伤模型和移植模型的近端横断量大于远端损伤模型；将自体PNS移植物移植到脑干损伤模型的损伤部位。第7天，与对侧比较，t组面神经核运动神经元存活率为105.8±3.8%，远端损伤组为102.4±5.2%；近端损伤组为94.6±7.4%，脑干损伤组为30.9±8.3%，移植组为43.7±6.2%。第28天，正常损伤组存活率为96.4±5.0%，远端损伤组90.2±3.0%，近端损伤组49.7±6.3%，脑干损伤组2.3±1.2%，移植组20.4±5.1%。明胶酶谱和免疫组化分析表明，miip -9在第1天在损伤部位表达，第3天达到峰值。MMP-2在第1天表达，持续7 d。原位酶谱图显示病变部位明胶酶活性。这些结果表明，本研究中使用的脑干病变模型导致大量神经元细胞死亡，而PNS自体移植物移植可以部分挽救这种死亡。在损伤早期，MIMPs可能在调节炎症细胞的迁移中发挥作用。自体PNS移植对退行性变性具有显著的神经保护作用。少

The aim of this study is to establish a model to investigate the unknown mechanism of retrograde neuronal cell death in the facial nucleus after axotomy at various lesions.In addition, the neuroprotective effects of autografted peripheral nerve tissues, and alteration of MMPs expression are investigated.The models include brainstem injury model ; the genu of the facial nerve tract in the brainstem is stereotactically transected, control injury model ; the brainstem near the facial nucleus is injured without transection of the facial nerve tract, distal injury model ; the facial nerve is cut at the stylomastoid foramen, proximal injury model ; the facial nerve is avuked at the stylomastoid foramen resulting in more proximal transection than the distal injury model, and transplanted model ; PNS autograft is transplanted to the injury site of the brainstem injury model.On day 7, compared with the contralateral side, the survival ratio of motoneurons of the facial nuclei is 105.8±3.8% in t … More he control injury group, 102.4±5.2% in the distal injury group; 94.6±7.4% in the proximal injury group, 30.9±8.3% in the brainstem injury group, 43.7±6.2% in the transplanted group. On day 28, the survival ratio is 96.4±5.0% in the control injury group, 90.2±3.0% in the distal injury group, 49.7±6.3% in the proximal injury group, 2.3±1.2% in the brainstem injury group, 20.4±5.1% in the transplanted group. In gelatin zymography and immunobistochemistry MIMiP-9 was expressed in injury site on day 1 with a peak on day 3.MMP-2 was expressed on day 1 and lasted for 7 days. In situ zymography showed gelatinase activity at the lesion site.These results suggest that the brainstem lesion model used in this study causes a massive neuronal cell death and this was partialiy rescued by the PNS autograft transplantation. MIMPs may play a role to regulate migration of inflammatory cells at the early stage of the injury.The transplantation of the PNS autograft has significant neuroprotective effects for retrograde degeneration. Less