Zhang Shuyan, Zhang Qinli, Zhang John H, Qin Xinyue
Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China.
Front Biosci. 2008 May 1;13:6999-7007. doi: 10.2741/3205.
This study focused on the effect of electro-stimulation of fastigial nucleus on the expression of NgR and on axonal regeneration after focal cerebral ischemia-reperfusion in rats. Cerebral ischemia and reperfusion was induced by nylon monofilament. Ninety-six male SD rats were randomly divided into sham group and ischemic insult groups at 12 hours, 24 hours, and 1 to 3 weeks after cerebral ischemia-reperfusion. Reverse transcription-polymerase chain reaction (RT-PCR) was used to determine the changes of NgR mRNA expression. Immunohistochemistry was used to detect the expression of NgR protein and the state of axonal regeneration. Fastigial nucleus stimulation was applied at 2 hours after ischemia for one hour. The results demonstrated that NgR mRNA and protein in the infarcted cortex and hippocampus were significantly increased (p<0.01). The axons were grossly damaged at 24 h after cerebral ischemia-reperfusion when compared to the sham group. Fastigial nucleus stimulation decreased NgR mRNA and protein levels in the infarcted cortex and hippocampus (p<0.01) and improved axonal growth at 24 hours and 2 weeks after ischemia-reperfusion (p<0.05). These results suggest that electrostimulation of fastigial nucleus might provide a new strategy to promote CNS axonal regeneration.
本研究聚焦于电刺激小脑顶核对大鼠局灶性脑缺血再灌注后NgR表达及轴突再生的影响。采用尼龙单丝诱导脑缺血再灌注。96只雄性SD大鼠在脑缺血再灌注后12小时、24小时以及1至3周时被随机分为假手术组和缺血损伤组。运用逆转录聚合酶链反应（RT-PCR）来测定NgR mRNA表达的变化。采用免疫组织化学法检测NgR蛋白的表达及轴突再生状况。在缺血2小时后进行1小时的小脑顶核刺激。结果显示，梗死皮层和海马中的NgR mRNA及蛋白显著增加（p<0.01）。与假手术组相比，脑缺血再灌注24小时时轴突严重受损。小脑顶核刺激降低了梗死皮层和海马中NgR mRNA及蛋白水平（p<0.01），并在缺血再灌注24小时及2周时改善了轴突生长（p<0.05）。这些结果表明，电刺激小脑顶核可能为促进中枢神经系统轴突再生提供一种新策略。
