特异性调控前额叶皮质锥体细胞活性对大鼠内脏痛行为的影响

目的:通过光遗传学手段,特异性调控内侧前额叶皮质(medial prefrontal cortex,m PFC)锥体细胞活性的变化,观察对于大鼠内脏痛及焦虑行为的影响。方法:雄性成年大鼠分为3组,随机注入AAV_(2/9)-Ca MKII-mcherry,AAV_(2/9)-Ca MKII-ChR2-mcherry以及AAV_(2/9)-Ca MKII-Arch T-mcherry病毒,特异性感染锥体细胞。病毒注射4周后,将光纤埋入双侧m PFC内,之后通过给予蓝光或黄光刺激激活含ChR2或Arch T的神经元,观察对于大鼠内脏痛和焦虑行为的影响。结果:AAV注射很好地感染了m PFC内的锥体细胞,表达ChR2的大鼠经蓝光照射后Fos表达量增高,内脏痛反应和焦虑行为受到抑制。表达Arch T的大鼠经黄光刺激后Fos表达量降低,内脏痛反应和焦虑行为增加。结论:兴奋m PFC内的锥体细胞对于内脏痛和焦虑产生明显抑制,而抑制锥体细胞则增强内脏痛和焦虑行为。

Regulation of the activities of pyramidal cells in the medial prefrontal cortex of rats affected the visceral pain and anxiety

Objective:By applying optogenetic methods,we regulated the activities of pyramidal cells in the medial prefrontal cortex (mPFC) of rats and observed the possible changed behavioral effects for the visceral pain and anxiety.Methods:Adult male SD rats were randomly divided into 3 group and AAV2/9-CaMKII-mcherry,AAV2/9-CaMKII-ChR2-mcherry and AAV2/9-CaMKII-ArchT-mcherry were injected into the mPFC of different groups,respectively.After 4 weeks,optic fibers were implanted into both sides of the mPFC.Then we applied blue or yellow light through the optic fibers to observe the possible changed behavioral effects for rats'visceral pain and anxiety.Results:AAV affected the pyramidal cells of the mPFC exclusively.When applying blue light for the ChR2-expressing rats,the Fos expression was increased and the visceral pain and anxiety responses were inhibited.On the contrary,applying yellow light for the ArchT-expressing rats decreased the Fos expression and deteriorated the visceral pain and anxiety responses.Conclusion:Activation of pyramidal cells in the mPFC inhibits the visceral pain and anxiety responses,and inhibition of the pyramidal cells enhances the visceral pain and anxiety responses.