细胞周期调控对大鼠局灶性脑缺血后迟发性神经元死亡的影响

Effect of cell cycle regulation on delayed neuronal death in rats after focal cerebral ischemia

目的探讨细胞周期调控对脑神经细胞凋亡的影响。方法采用光化学方法制作大鼠局灶性缺血模型,术后立即腹腔注射细胞周期抑制剂Olomoucine进行干预。HE染色来测定皮层梗死灶的体积;应用免疫组织化学法观察缺血后第3天假手术组、缺血对照组和干预组大鼠损伤侧皮层病灶周围凋亡神经细胞的表达;聚丙烯酰胺凝胶电泳(Western blot)和半定量逆转录-聚合酶链式反应(RT-PCR)观察Caspase-3蛋白及mRNA的表达。结果 HE染色显示对照组梗死灶明显大于干预组;免疫组织化学可见病灶周围凋亡神经细胞的阳性表达,干预组较假手术组显著增高,但明显低于对照组(P<0．05);Western blot和RT-PcR显示Caspase-3蛋白和mRNA的表达,干预组较假手术组增高(P<0．05),而较对照组明显降低(P<0．05)。结论脑缺血损伤后细胞周期调控参与了迟发性神经元的死亡过程。

Objective To study the effect of cell cycle regulation on apoptosis of cerebral nerve cells. Methods Focal ischemia models were achieved by photochemistry method. Olomoucine （4mg/kg,i. p） was gived at once after operation in the treated groups. Rats were killed 3 days after operation. Their brain were sectioned and sections were stained with HE. In the cortex ipsilateral to the side of focal ischemia,the number and anatomic distribution of apoptosis neural cell were detected by immunohistochemistry. The expression of caspase-3 protein and mRNA were assessed by Western blot and RT-PCR. Results Compared with rats in treated group,the areas of the cerebral infarct region of rats in ischemic group were larger. Apoptosis cells density appeared higher in treated group than in sham group near the infarct region of the ipsilateral cortex,but significantly lower than ischemic group. The expression of Caspase-3 protein and mRNA by Westernblot and RT-PCR analysis in treated group was higher than in sham group,but significantly lower than in ischemic group. Conclusion The studys showed that cell cycle regulation plays an important role in the effect on process of neuronal delayed death after cerebral ischemic damaged.