癫痫大鼠小胶质细胞活化与P2Y12受体的表达及Purα的影响

摘要

目的 研究急性癫痫状态下小胶质细胞活化与P2Y12受体的表达,以及Purα对P2Y12受体表达的影响.方法 用免疫组织化学方法检测大鼠急性癫痫持续状态后不同时间点海马组织中由IBA1标记的小胶质细胞的活化;用Western blot检测癫痫状态下海马组织中P2Y12受体和Purα的表达水平,以及检测Purα在癫痫状态下对P2Y12受体表达水平的影响.结果 癫痫组大鼠海马组织中的小胶质细胞被激活,表现为胞体增大、数量增多、突起数量增多且长度变短.癫痫不同时间点小胶质细胞活化的程度不同,癫痫2h时,小胶质细胞活化最为明显;癫痫4h时,活化的小胶质细胞数量开始减少;癫痫8h时,小胶质细胞活化程度最低.随着癫痫状态的持续,P2Y12受体表达水平呈现先上升后下降趋势,在癫痫3h时其表达水平最高,与正常对照组比较差异有统计学意义(P<0.05).癫痫持续2h时,Purα过表达组的P2Y12受体的表达水平高于对照组(P<0.05),Purα沉默组的P2Y12受体的表达水平低于对照组和正常组(P均<0.05).结论 癫痫持续状态下,小胶质细胞发生活化;P2Y12受体的表达与小胶质细胞活化状态有关;Purα能够上调P2Y12受体的表达水平.%Objective To investigate the activation and P2Y12 receptor expression after induction of status epilepticus of rats and the effects of Purαprotein on P2Y12 expression.MethodsThe immunohistochemistry was employed to detect the microglial activation of rat hippocampus tissues at different time points after the induction of status epilepticus. Western blot was used to check the P2Y12 receptor expression in the status epilepticus as well as under the conditions when Purαwas over-expressed and/or knocked-down the changes of microglial activation and P2Y12 expression after induction of status epilepticus.ResultsThe persistent status epilepticus could induce the obvious microglial activation. The activated microglia presented with the long processes,increasing numbers of dendrites and cells and enlarging cell body and branch rod or amoeboid shaped cell bodies,and with disordered arrangement. At different time points of status epileptics,the degree of microglial activation was different and the microglial activation was at its peak in 2 hours after the status epilepticus while it tapered off from the 4th hours and at its lowest in the 8th hours after the status epilepticus. The level of P2Y12 receptor protein expression was also different from the status epilepticus and it presented the higher level of expression and then dropped off. Overexpression of Purαprotein could remarkably upregulate the expression of P2Y12 receptor protein expression.ConclusionIn the persistent status epilepticus,microglial cells could be activated. The expression of P2Y12 receptor protein was associated with the status of microglial activation. Purαprotein could activate P2Y12 receptor protein expression.