Glucocorticoid enhancement of memory requires arousal-induced noradrenergic activation in the basolateral amygdala
Glucocorticoid enhancement of memory requires arousal-induced noradrenergic activation in the basolateral amygdala
复制标题
DOI：
10.1073/pnas.0601874103
复制
发表时间：
2006-04-25
影响因子：
11.1
通讯作者：
McGaugh, JL
中科院分区：
文献类型：
--
作者：
Roozendaal, B;Okuda, S;McGaugh, JL
大量的证据表明，糖皮质激素增强了长期记忆的巩固，对于情绪激动的经历，但对于不那么激动或中性的信息。然而，以前的研究还没有确定这种唤醒诱导的选择性的基础。在这里，我们报告的发现，内源性去甲肾上腺素能激活杏仁核（BLA）的基底外侧复合体的情绪唤醒诱导是必不可少的，使糖皮质激素记忆增强。对象识别训练后立即给予皮质酮增强了本地雄性大鼠的24小时记忆，但不是以前习惯于训练环境的大鼠，以减少新奇诱导的情绪唤起。β-肾上腺素能受体拮抗剂普萘洛尔全身给药或进入BLA阻断皮质酮诱导的记忆增强。此外，在习惯性大鼠中，皮质酮激活BLA神经元，通过磷酸化cAMP反应元件结合（pCREB）免疫反应性水平进行评估，并增强记忆，只有当去甲肾上腺素释放刺激的α（2）-肾上腺素受体拮抗剂育亨宾管理。这些研究结果强烈表明，糖皮质激素和情绪唤醒诱导的去甲肾上腺素能激活BILA的协同作用构成了一种神经机制，糖皮质激素可以选择性地增强记忆巩固情绪唤起的经验。
Considerable evidence indicates that glucocorticoid hormones enhance the consolidation of long-term memories for emotionally arousing experiences but not that for less arousing or neutral information. However, previous studies have not determined the basis of such arousal-induced selectivity. Here we report the finding that endogenous noradrenergic activation of the basolateral complex of the amygdala (BLA) induced by emotional arousal is essential in enabling glucocorticoid memory enhancement. Corticosterone administered immediately after object recognition training enhanced 24-h memory of native male rats but not that of rats previously habituated to the training context in order to reduce novelty-induced emotional arousal. The beta-adrenoceptor antagonist propranolol administered either systemically or into the BLA blocked the corticosterone-induced memory enhancement. Further, in habituated rats, corticosterone activated BLA neurons, as assessed by phosphorylated cAMP response element binding (pCREB) immunoreactivity levels, and enhanced memory only when norepinephrine release was stimulated by administration of the alpha(2)-adrenoceptor antagonist yohimbine. These findings strongly suggest that synergistic actions of glucocorticoids and emotional arousal-induced noradrenergic activation of the BILA constitute a neural mechanism by which glucocorticoids may selectively enhance memory consolidation for emotionally arousing experiences.