Roozendaal Benno, Hui Gabriel K, Hui Isabel R, Berlau Daniel J, McGaugh James L, Weinberger Norman M
Center for the Neurobiology of Learning and Memory, Department of Neurobiology and Behavior, University of California, Irvine, CA 92697-3800, USA.
Neurobiol Learn Mem. 2006 Nov;86(3):249-55. doi: 10.1016/j.nlm.2006.03.003. Epub 2006 Apr 21.
The present experiment examined whether posttraining noradrenergic activity within the basolateral complex of the amygdala (BLA) is required for mediating the facilitating effects of acutely administered glucocorticoids on memory for auditory-cue classical fear conditioning. Male Sprague-Dawley rats received five pairings of a single-frequency auditory stimulus and footshock, followed immediately by bilateral infusions of the beta1-adrenoceptor antagonist atenolol (0.5 microg in 0.2 microl) or saline into the BLA together with a subcutaneous injection of either corticosterone (3.0 mg/kg) or vehicle. Retention was tested 24 h later in a novel test chamber and suppression of ongoing motor behavior served as the measure of conditioned fear. Corticosterone facilitated memory as assessed by suppression of motor activity during the 10-s presentation of the auditory stimulus and intra-BLA administration of atenolol selectively blocked this corticosterone-induced memory enhancement. These findings provide evidence that, as found with other emotionally arousing tasks, the enhancing effects of corticosterone on memory consolidation of auditory-cue fear conditioning require posttraining noradrenergic activity within the BLA.
本实验研究了杏仁核基底外侧复合体（BLA）内训练后去甲肾上腺素能活动是否是急性给予糖皮质激素对听觉线索经典恐惧条件反射记忆产生促进作用的中介因素。雄性Sprague-Dawley大鼠接受五次单频听觉刺激与足部电击配对，随后立即向BLA双侧注入β1肾上腺素能受体拮抗剂阿替洛尔（0.5微克/0.2微升）或生理盐水，并皮下注射皮质酮（3.0毫克/千克）或溶剂。24小时后在一个新的测试箱中测试记忆保持情况，抑制正在进行的运动行为作为条件性恐惧的指标。通过在10秒听觉刺激期间抑制运动活动评估，皮质酮促进了记忆，而向BLA内注射阿替洛尔选择性地阻断了这种皮质酮诱导的记忆增强。这些发现提供了证据，即与其他情绪唤起任务一样，皮质酮对听觉线索恐惧条件反射记忆巩固的增强作用需要BLA内训练后的去甲肾上腺素能活动。
