脑缺血后可逆性蛋白磷酸化水平变化及电刺激对其的影响

目的研究脑缺血后神经元损伤过程中可逆性蛋白磷酸化水平变化及电刺激对其的影响。方法采用改良Longa线栓法制成永久性大脑中动脉闭塞动物模型,运用免疫荧光染色技术,检测神经颗粒素磷酸化水平(p-Ng)以及钙调神经磷酸酶(CaN)在脑缺血及电刺激不同时间内的变化情况。结果脑缺血3hp-Ng即开始增加,脑缺血1d后p-Ng水平达到高峰,缺血组为120.7±4.9,电针组为100.2±6.0(P<0.05);而缺血6hCaN开始发挥去磷酸化作用,至缺血3d后CaN免疫水平达到高峰,缺血组为44.0±3.7,电针组为48.9±3.3(P<0.05);随缺血时间延长,其免疫活性渐丧失。结论急性缺血性脑卒中,蛋白磷酸化/去磷酸化作用参与了缺血神经元损伤过程。电针刺激有可能通过维持蛋白磷酸化/去磷酸化的平衡,而发挥保护缺血神经元损伤的作用。

Expression of Reversible Phosphorylation of Protein and Effects of Electro- stimulation During Focal Cerebral Ischemia in Rats

Objective To study levels of reversible phosphorylation of protein and effects of electro-stimulation during ischemic cerebral injury in rats.Methods The model of permanent middle cerebral artery occlusion (MCAO) was established with Longa's method. The expression of p-Ng and CaN were measured by immunofluorescent staining method. Results Level of p-Ng began to increase post-ischemic 3 hours,reached its maximum after MCAO for one day (P<0.05).With brain ischemia degeneration it decreased. The immuno-expression of CaN began to increase post-ischemic 6 hours,and reached its maximum after MCAO at 3 days (P<0.05),then gradually decreased.Conclusions The balance of reversible phosphorylation of protein was broken during ischemic cerebral injury. The result suggested that protein phosphorylation/disphosphorylation were related the course of ischemic neuron injury. Electro-stimulation might maintain the balance between protein phosphrylation and dephosphorylationm to protect ischemic neuron.