蛇毒型神经生长因子在脑缺血再灌注损伤后神经重塑过程中对Doublecortin的影响

The effect of viper venom nerve growth factor(vNGF)on neuronal plasticity in rat after cerebral ischemia reperfusion injury

目的探讨经侧脑室给予蛇毒型神经生长因子(viper venom nerve growth factor,vNGF)对脑缺血再灌注损伤后大鼠神经重塑的影响。方法雄性Wistar大鼠90只随机分成5组:vNGF-25u组、vNGF-50u组、vNGF-100u组、缺血再灌注(I/R)组和假手术(S)组,每组18只。造模后每日根据Longa评分评价大鼠神经功能情况。于2、7、14d分批处死大鼠取脑组织提取总RNA,用荧光定量PCR检测Doublecortin(DCX)mRNA的表达。结果 (1)大鼠的神经功能评分随着时间延长而降低;同一时间下,vNGF各组评分低于I/R对照组,vNGF各组评分随着给药浓度增高而降低;(2)随着时间延长,DCX mRNA在各组的表达从2d开始逐渐增加,在7d达最高峰,14d时有所下降。术后同一时间,DCX mRNA在蛇毒组的表达高于在I/R对照组,并且DCX mRNA在vNGF-50U组的表达为蛇毒组中最高。结论 vNGF可通过增强DCX迁移效应促进神经重塑和恢复神经功能缺损。

Objective To investigate the significance and mechanism of intracerebroventricular injection of viper venom nerve growth factor（vNGF） in rat neural plasticity after cerebral ischemia reperfusion injury. Methods Ninety wist- ar male rat were randomly assigned into vNGF-25u group（ n = 18 ）, vNGF-50u group（ n = 18 ） , vNGF-100u group（ n = 18 ） , isehemia reperfusion（I/R） group（ n = 18） and sham operated（s） group. Neurofunctional status of rats was evaluated on the basis of Longa standardization everyday after surgery. The expression of 13-tubulin mRNA and DCX mRNA in rat brain tis- sues which were collection on 2d,7d and 14d after surgery were evaluated by the real time PCR. Results The scores of neurofunctional status of rats began to decrease after surgery. The scores of the vNGF groups were less than the I/R group at the same time. The more vNGF were injected,the less scores were received. Expression of DCX mRNA in all of groups began to increase on 2d after surgery,reached the peak on 7d and then decreased on 14d. At the same time,expression of DCX mRNA in the vNGF groups was more than in I/R group. Expression of DCX mRNA in vNGF-50u group was more than other groups. Conclusions The vNGF could accelerate neural plasticity and restore neurofunctional defect through strengthening the migratory effect of DCX.