马来酸桂哌齐特对脑缺血大鼠模型胞外信号调节激酶表达的影响

目的观察马来酸桂哌齐特预处理对大鼠脑缺血半暗带区胞外信号调节激酶(ERK1/2)磷酸化表达的影响,探讨其对脑缺血的保护作用及可能的作用机制。方法采用改良线栓法建立大鼠永久性大脑中动脉阻塞(pMCAO)模型。SD大鼠随机分为1马来酸桂哌齐特组(pMCAO模型大鼠,n=57。尾静脉注射马来酸桂哌齐特3.0 mg·kg-1,×5d);2对照组(pMCAO模型大鼠,n=57。尾静脉注射生理盐水0.5 mL,×5 d);3假手术组(不插线栓,n=50。尾静脉注射生理盐水0.5 mL,×5 d);4正常组(n=3,不做任何处理)。应用TTC染色法测定梗死体积,蛋白印迹法和免疫组化法检测不同时间点(术后3、6、24、48和72 h)缺血半暗带区ERK蛋白的表达。结果马来酸桂哌齐特组与对照组比较,梗死体积减少17.91%(P=0.001)。马来酸桂哌齐特组缺血半暗带pERK1/2表达于3 h开始增加,24 h达高峰[为正常的(5.75±0.70)倍]后逐渐降低,72 h仍为正常的(2.89±0.51)倍,各时间点与正常组比较,均差异有显著统计学意义(P0.01)。6、24和48 h 3个时间点,马来酸桂哌齐特组缺血半暗带内pERK1/2表达较对照组增加(P0.05)。pERK的免疫组化检测示马来酸桂哌齐特预处理能上调缺血半暗带区内ERK磷酸化表达(P0.05)。结论马来酸桂哌齐特预处理可减少脑梗死体积,并能上调缺血半暗带区的ERK磷酸化表达;参与MAPK信号通路、上调缺血半暗带区内ERK磷酸化的表达,可能是其保护缺血性脑损伤的机制之一。

Effect of Cinepazide Maleate on the Expression of ERK1/2 in the Cerebral Ischemia Rat Model

Aim To observe the influence of cinepazide maleate pretreatment on the expression of extracellular signal-regulated kinase（ERK1/2） phosphorylation in cerebral ischemic penumbra in the permanent middle cerebral artery occlusion（pMCAO） model rats, and explore its neuroprotective function and other possible mechanism. Methods The pMCAO model rats were established by modified suture embolization method. SD rats were randomly divided into a cinepazide maleate group（n=57）（pMCAO model rats, tail intravenous injection of cinepazide maleate 3.0 mg·kg^-1 for 5 days）, a control group（n=57）（pMCAO model rats, tail intravenous injection of normal saline 0.5 mL·d-1 for 5 days） and asham group（n=50）（the same model of pMCAO but no suture inserted, tail intravenous injection of normal saline 0.5 mL·d-1 for 5 days）. Infarct volume was determined by TTC staining, the expression of ERK1/2 phosphorylation in cerebral ischemic penumbra at different time points after cerebral ischemia（3, 6, 24, 48 and 72h） were detected by Western blotting and immunohistochemistry. Results Compared with the control group, the infarct volum of cinepazide maleate groupe reduced by 17.91%（P=0.001）. The expression of pERK1/2 in ischemic penumbra of cinepazide maleate group began to increase at 3 hours of ischemia, and reached the peak at 24 hours [（5.75±0.70） times of the normal]. Then it was still（2.89±0.51） times of the normal at 72 hours of ischemia. Compared with the normal group, each time point have significant statistical differences（P〈0.01）. At the three time points（6 h, 24 h and 48 h）, the expression of pERK1/2 of cinepazide maleate group compared with that of the control group increased definitely in the ischemic penumbra（P〈0.05）. Through immunohistochemistry staining, it indicated the cinepazide maleate pretreatment could up-regulate the expression of phosphorylated ERK in ischemic penumbra（P〈0.05）. Conclusion Cinepazide maleate pretreatment could reduce infarct volume and