Abumaria Nashat, Luo Lin, Ahn Matae, Liu Guosong
School of Medicine, Tsinghua-Peking Center for Life Sciences, Tsinghua University, 100084 Beijing, China.
Behav Pharmacol. 2013 Aug;24(4):255-63. doi: 10.1097/FBP.0b013e32836357c7.
Enhancement of pattern separation could be helpful in improving the quality of normal daily learning and in treating individuals with cognitive impairment and certain psychiatric disorders. Previously, we have shown that elevating brain magnesium, by a novel magnesium compound (magnesium-L-threonate; MgT), enhances extinction of fear memory without enhancing amygdala-dependent fear memory. Here, we investigated the effects of MgT treatment on contextual-fear memory and subsequent pattern separation. Sprague-Dawley male rats were treated with MgT for 4 weeks and memory was evaluated using a spatial-context fear conditioning task. The pattern separation ability of MgT-treated rats was assessed using a spatial-context-discrimination task. MgT treatment did not enhance the retention of contextual-fear memory. Interestingly, the ability to discriminate between two, more or less distinct, contexts was enhanced in MgT-treated rats. Our results suggest that elevation of brain magnesium might be helpful in enhancing spatial-context discrimination and/or pattern separation besides preventing aversive-event-induced overgeneralization of fear.
增强模式分离可能有助于提高日常正常学习的质量，以及治疗认知障碍患者和某些精神疾病患者。此前，我们已经表明，通过一种新型镁化合物（L-苏糖酸镁；MgT）提高大脑镁水平，可增强恐惧记忆的消退，而不会增强杏仁核依赖性恐惧记忆。在此，我们研究了MgT治疗对情境恐惧记忆及随后模式分离的影响。将斯普拉格-道利雄性大鼠用MgT治疗4周，并使用空间情境恐惧条件任务评估记忆。使用空间情境辨别任务评估MgT治疗大鼠的模式分离能力。MgT治疗并未增强情境恐惧记忆的保持。有趣的是，在MgT治疗的大鼠中，区分两个或多或少不同情境的能力增强了。我们的结果表明，提高大脑镁水平除了防止厌恶事件引起的恐惧过度泛化外，可能有助于增强空间情境辨别和/或模式分离。
