该研究采用一次性步入法测试大鼠被动回避行为,以局部EEG功率变化作为蝇蕈醇失活前额叶下边缘区的效果指标,观察训练期和24 h后重测试时大鼠进入暗箱的潜伏期,旨在探讨激活前额叶下边缘区GABAA受体,可逆性失活该区神经元对大鼠被动回避记忆巩固过程的影响。结果发现,蝇蕈醇可显著降低大鼠前额叶下边缘区EEG总功率,但其被动回避作业重测试潜伏期与对照组无明显差异;即大鼠前额叶下边缘区GABAA受体被激活,导致该区神经兴奋性可逆性降低,但不影响被动回避记忆的巩固过程。
In this study, one-trial step-through task was applied to reveal the effect of prefrontal infralimbic cortex GABAA receptor agitating on passive avoidance memory consolidation in rats. Immediately after training (with shock), GABAA receptor agonist, muscimol (0.5 μg/0.25 μL) or saline (0.25 μL) was infused into the test animal's infralimbic cortex, then, the latencies of rats stepping through the dark room were recorded. Meanwhile, local EEG power was adopted as index of the inactivation effect of muscimol. The step-through latencies of muscimol group were comparable(P〉0.05)with saline group, but their local EEG power had decreased significantly (P〈0.05). These results suggest that the inactivation of infralimbic cortex would not demolish the passive avoidance memory consolidation of rats.