Department of Psychiatry, Charité University Berlin, Campus Benjamin Franklin, Eschenallee 3, 14050 Berlin, Germany.
Stress. 2013 Mar;16(2):191-201. doi: 10.3109/10253890.2012.708951. Epub 2012 Aug 2.
Major depressive disorder (MDD) has been associated with alterations in the noradrenergic system and impaired memory function. In turn, enhanced memory function has been associated with noradrenergic stimulation. In this study, we examined whether noradrenergic stimulation would differentially improve memory function in patients with MDD and healthy controls. In a placebo-controlled crossover study, 20 patients with MDD and 18 age- and sex-matched healthy controls received either placebo or 5 mg of yohimbine, an alpha-2-adrenoceptor antagonist that causes increased noradrenergic activity, orally before memory testing. A word list paradigm was used to test memory consolidation. Furthermore, the autobiographical memory test assessing memory retrieval and a working memory test were administered. Salivary alpha-amylase and blood pressure were measured. Yohimbine improved memory consolidation (word list learning) across groups (main effect of yohimbine: p = 0.05). This effect was more prominent in depressed patients compared with controls (post hoc t-test: MDD p = 0.01, controls p = 0.77). Memory retrieval (autobiographical memory specificity) and working memory were not affected by yohimbine. Across groups, yohimbine administration resulted in an increase in blood pressure and alpha-amylase. In sum, these results further support the hypothesis that noradrenergic stimulation enhances memory consolidation. The mechanism by which yohimbine leads to stronger memory consolidation in depressed patients compared with healthy controls remains to be elucidated.
重度抑郁症（MDD）与去甲肾上腺素能系统的改变和记忆功能受损有关。反过来，增强的记忆功能与去甲肾上腺素能刺激有关。在这项研究中，我们研究了去甲肾上腺素能刺激是否会对 MDD 患者和健康对照组的记忆功能产生不同的改善作用。在一项安慰剂对照交叉研究中，20 名 MDD 患者和 18 名年龄和性别匹配的健康对照组在记忆测试前口服安慰剂或 5 毫克育亨宾，一种增加去甲肾上腺素能活性的α-2-肾上腺素受体拮抗剂。使用单词列表范式测试记忆巩固。此外，还进行了自传体记忆测试以评估记忆检索和工作记忆测试。测量唾液淀粉酶和血压。育亨宾改善了所有组的记忆巩固（单词列表学习）（育亨宾的主要作用：p=0.05）。与对照组相比，这种作用在抑郁症患者中更为明显（事后 t 检验：MDD p=0.01，对照组 p=0.77）。记忆检索（自传体记忆特异性）和工作记忆不受育亨宾影响。在所有组中，育亨宾给药导致血压和α-淀粉酶升高。总之，这些结果进一步支持了去甲肾上腺素能刺激增强记忆巩固的假设。育亨宾导致抑郁症患者的记忆巩固比健康对照组更强的机制仍有待阐明。
