前边缘皮质Kv7.3钾通道在甲基苯丙胺条件性位置偏爱中的作用

The role of Kv7.3 of prelimbic cortex in Methamphetamine induced conditioned place preference in mice

目的 探究前边缘皮质在甲基苯丙胺(methamphetamine,METH)诱导小鼠条件性位置偏爱(conditioned place preference,CPP)中的作用,以及电压门控型钾离子通道Kv7.3在前边缘皮质(prelimbic cortex,Prl)内的调控机制。方法 给予C57BL/6J小鼠腹腔注射METH(2mg/kg)建立CPP成瘾模型。通过化学遗传学技术,在前边缘皮质内注射hM4di-mcherry病毒载体,经N-氧化氯氮平诱导激活小G蛋白Gi信号通路,观察Prl脑区在METH致CPP中的作用。应用PCR、Western Blot检测Prl内Kv7.3的表达情况。在Prl脑区埋置套管,定位注射瑞替加滨(Kv7钾通道激动剂),观察对CPP评分的影响。结果 METH导致Prl内神经元明显活化并降低Kv7.3表达水平。通过化学遗传学特异性沉默Prl脑区神经元,明显减弱CPP分数,激活Prl脑区的Kv7.3通道亦明显降低CPP评分。结论 前边缘皮质参与了METH诱导CPP的形成,Kv7.3钾离子通道蛋白在该过程中发挥着重要作用。

Objective To investigate the role of prelimbic cortex(Prl) in methamphetamine(METH) induced conditioned place preference(CPP) in mice, and further identify the regulatory mechanism of Kv7.3 in Prl cortex. Methods In this study, C57BJ/6J mice were intraperitoneally injected with METH(2mg/kg)to establish animal model of CPP. Through chemical genetic manipulation, hM4di-mcherry virus was injected into Prl, by Clozapine N-oxide(CNO),s activation of small G protein signaling, to analyze the role of Prl in METH induced CPP. Then, qPCR and Western blot were used to detect the expression of Kv7.3 in METH addiction mice. Finally, cannulas were implanted stereotactically into Prl to observe the resulting effect of Kv7 channel agonist retigabine on CPP score. Results METH activated neurons in Prl and decreased the expression level of Kv7.3 significantly. CPP score was obviously reduced after specific inhibition of Prl neurons by chemical genetics. Also, Kv7.3 channel agonist retigabine decreased CPP score evidently.Conclusions Prl takes part in the regulation of METH induced CPP and Kv7.3 channel plays a crucial role in it.