Su Ying, Wang Feng, Zhao Shi-guang, Pan Shang-ha, Liu Ping, Teng Yan, Cui Hao
Department of Ophthalmology, First Clinical College of Harbin Medical University, Harbin, China.
Mol Vis. 2008 Feb 4;14:268-73.
The axonal regeneration of retinal ganglion cells (RGCs) after optic nerve (ON) crush was investigated both in vivo and in vitro on Nogo-A/B/C knockout mice.
The study used 20 Nogo-A/B/C knockout mice in the experimental group, and 20 C57BL/6 mice in the control group. Partial ON injury was induced by using a specially designed ON clip to pinch the ON 1 mm behind the mouse eyeball with 40 g pressure for 9 s. The left ON was injured in both groups, but the right ON was left untouched in the control group. Nogo-A/B/C mRNA was studied by in situ hybridization in both groups. GAP-43 was studied by immunofluorescence staining on frozen sections. RGCs were purified and cultured in DMEM medium containing B-27. Cells were then immunostained with both Thy1.1 and GAP-43 antibodies. The axonal growth of RGCs was calculated by a computerized image analyzer.
GAP-43 expression was significantly higher in the experimental group than in the control group (p<0.01). GAP-43 antibody binding was demonstrated in the axons of cultured RGCs. Axonal growth was significantly more active at every observed time point in the experimental group than in the control group (F=43.25, 32.16; p<0.01).
Nogo genes play an inhibitive role in the axonal regeneration after ON injury, while Nogo-knockout is an effective way to eliminate this inhibition and accelerate axonal regeneration.
在体内和体外对Nogo - A/B/C基因敲除小鼠研究视神经挤压伤后视网膜神经节细胞（RGCs）的轴突再生情况。
实验组采用20只Nogo - A/B/C基因敲除小鼠，对照组采用20只C57BL/6小鼠。使用特制的视神经夹在小鼠眼球后1 mm处以40 g压力夹捏视神经9 s，诱导部分视神经损伤。两组均损伤左侧视神经，但对照组右侧视神经未处理。两组均通过原位杂交研究Nogo - A/B/C mRNA。通过对冰冻切片进行免疫荧光染色研究生长相关蛋白43（GAP - 43）。将RGCs纯化并培养于含B - 27的DMEM培养基中。然后用Thy1.1和GAP - 43抗体对细胞进行免疫染色。通过计算机图像分析仪计算RGCs的轴突生长情况。
实验组GAP - 43表达明显高于对照组（p<0.01）。在培养的RGCs轴突中证实有GAP - 43抗体结合。在每个观察时间点，实验组轴突生长均明显比对照组活跃（F = 43.25, 32.16；p<0.01）。
Nogo基因在视神经损伤后的轴突再生中起抑制作用，而敲除Nogo基因是消除这种抑制并加速轴突再生的有效方法。
