Zhu Zhaowei, Huang Yanyan, Zou Xiaoyan, Zheng Canbin, Liu Jianghui, Qiu Longhai, He Bo, Zhu Qingtang, Liu Xiaolin
a Department of Plastic and Reconstructive Surgery , The First Affiliated Hospital of Sun Yat-sen University , Guangzhou , China.
c Department of Neurology , The First Affiliated Hospital of Sun Yat-sen University , Guangzhou , China.
Neurol Res. 2017 Nov;39(11):1014-1021. doi: 10.1080/01616412.2017.1365423. Epub 2017 Aug 24.
We have demonstrated that angiogenesis in acellular nerve allografts (ANAs) can promote neuroregeneration. The present study aimed to investigate the microvascular regeneration pattern of ANAs in Sprague-Dawley (SD) rats.
Sixty male SD rats were randomly divided into an autologous group and a rat acellular nerve allograft group (rANA), and 10-mm sciatic nerve defects were induced in these rats. On the 7th, 14th and 21st days after surgery, systemic perfusion with Evans Blue (EB) or lead oxide was performed on the rats through carotid intubation. Samples were then collected for gross observation, and the microvessels in the nerves were reconstructed through microscopic CT scans using MIMICS software. The vascular volume fraction (VF, %) and microvessel growth rate (V, mm/d) in both groups were then measured, and 1 month after surgery, NF-200 staining was performed to observe and compare the growth condition of the axons.
Early post-operative perfusion with gelatin/EB showed EB permeation around the acellular nerve. Perfusion with gelatin/lead oxide showed that the blood vessels had grown into the allograft from both ends 7 days after the operation. Fourteen days after the operation, the microvessel growth rate of the autologous group was faster than that of the rANA group (0.39 ± 0.17 mm/d vs. 0.26 ± 0.14 mm/d, p < 0.05), and the vascular VF was also higher than that of the rANA group (8.92% ± 1.54% vs. 6.31% ± 1.21%, p < 0.05). Twenty-one days after the operation, the blood vessels at both ends of the allograft had connected to form a microvessel network. The growth rate was not significantly different between the two groups; however, the vascular VF of the autologous group was higher than that of the rANA group (12.18% ± 2.27% vs. 9.92% ± 0.84%, p < 0.05). One month after the operation, the NF-200 fluorescence (IOD) in the autologous group significantly increased compared with that of the rANA group (540,278 ± 17,424 vs. 473,310 ± 14,636, respectively, p < 0.05), suggesting that the results of the repair after nerve injury were significantly better in the autologous group than in the rANA group.
Both the autologous nerve and ANAs rely on the permeation of tissue fluids to supply nutrients during the early stage, and microvessel growth mainly starts at both ends of the graft and enters the graft along the long axis. Compared to ANAs, the growth speed of revascularization in autologous nerve grafts was faster, leading to a better outcome in the autologous nerve group.
我们已经证明去细胞异体神经移植物（ANAs）中的血管生成可以促进神经再生。本研究旨在探讨ANAs在Sprague-Dawley（SD）大鼠体内的微血管再生模式。
将60只雄性SD大鼠随机分为自体神经组和大鼠去细胞异体神经移植组（rANA），并在这些大鼠中造成10毫米的坐骨神经缺损。术后第7、14和21天，通过颈动脉插管对大鼠进行伊文思蓝（EB）或氧化铅全身灌注。然后收集样本进行大体观察，并使用MIMICS软件通过显微CT扫描重建神经中的微血管。随后测量两组的血管体积分数（VF，%）和微血管生长速率（V，mm/d），术后1个月进行NF-200染色，以观察和比较轴突的生长情况。
术后早期用明胶/EB灌注显示EB在去细胞神经周围渗透。用明胶/氧化铅灌注显示术后7天血管已从两端长入异体移植物。术后14天，自体神经组的微血管生长速率快于rANA组（0.39±0.17 mm/d对0.26±0.14 mm/d，p<0.05），血管VF也高于rANA组（8.92%±1.54%对6.31%±1.21%，p<0.05）。术后21天，异体移植物两端的血管已连接形成微血管网络。两组的生长速率无显著差异；然而，自体神经组的血管VF高于rANA组（12.18%±2.27%对9.92%±0.84%，p<0.05）。术后1个月，自体神经组的NF-200荧光（IOD）与rANA组相比显著增加（分别为540278±17424对473310±14636，p<0.05），表明自体神经组神经损伤后的修复效果明显优于rANA组。
自体神经和ANAs在早期均依赖组织液渗透来供应营养，微血管生长主要从移植物两端开始并沿长轴进入移植物。与ANAs相比，自体神经移植物中血管再生的速度更快，导致自体神经组的结果更好。
