摘要
目的:探讨条件性恐惧消退早期(1周内)大鼠记忆保持成绩和内侧前额叶皮层边缘下区α钙调素依赖性蛋白激酶Ⅱ(αCaMKⅡ)的动态变化。方法:将70只成年雄性SD大鼠随机分为正常对照组、恐惧消退组和恐惧对照组,其中恐惧对照组为条件恐惧建立后不进行消退训练,恐惧消退组为条件恐惧建立24 h后进行消退训练,采用以声音为提示的足底电击建立大鼠恐惧记忆,然后仅给予声音信号进行恐惧消退训练。在恐惧消退后第1、3、7天分别进行消退保持测试,并在各时间点取边缘下区标本进行αCaMKⅡ的免疫组织化学检测。结果:在消退保持过程中,恐惧对照组和恐惧消退组大鼠消退成绩整体呈上升趋势,但均低于正常对照组,恐惧消退组消退成绩好于恐惧对照组(P<0.01);恐惧对照组和恐惧消退组大鼠边缘下区αCaMKⅡ免疫反应阳性物质逐渐增加,但均低于正常对照组,第1天无明显不同,第3、7天恐惧消退组αCaMKⅡ免疫反应阳性物质均低于恐惧对照组(P<0.01)。结论:恐惧消退训练后3~7 d,边缘下区αCaMKⅡ水平变化与恐惧记忆消退训练相关。
Objective: To observe the expression change of α calmodulin kinase Ⅱ(αCaMK Ⅱ )in infra-limbic cortex of medial prefrontal cortex of adult rats in the early stage of fear extinction. Methods:Seventy rats were randomly divided into normal control ,fear extinction and fear control group. The fear extinction training was not implemented in fear control group. The fear extinction group were trained to extinct fear with sound signal at 24 hours after fear established by sound hint of planter electric shock. The expressions of αCaMKⅡ in infra-limbic cortex were detected by immunohistochemistry at 1,3 and 7 days after fear extinction. Results: The expression of αCaMK Ⅱ in fear extinction and fear control group increased gradually, which was lower than that in normal control group. The fear extinction group were better than that in fear control group (P 〈 0.01 ). The immunoreactivities of αCaMKⅡ in infra- limbic cortex of fear extinction and fear control group increased gradually, which were lower than that in normal control group. The immunoreactivities of αCaMK Ⅱ in fear extinction group were lower than that in fear control group at 3 and 7 days after fear extinction (P 〈 0.01 ),but no significant difference at day 1. Conclusions: The αCaMK Ⅱ level in infra-limbic cortex is consistent with the extinction memory at 3 and 7 days after fear extinction training.
出处
《蚌埠医学院学报》
CAS
2013年第4期381-383,共3页
Journal of Bengbu Medical College
基金
安徽省高校省级科学研究基金资助项目(KJ2011B099)