Identification of suicide candidate genes in amygdala and its application to neuroimaging studies

1.基于76例以心境障碍为主的患者的自杀未遂病史，我们研究了与自杀相关的临床和心理特征。绝望而不是抑郁、40岁以下患者的攻击性和神经质与自杀有关。对死亡的看法与自杀无关。我们对自杀脑中杏仁核的mRNA表达进行了分析。鉴定出21个基因表达上调，9个基因表达下调。在表达增加的基因中，14-3-3ε基因的多态性与自杀有关。表达降低的基因的任何多态与自杀无关。在影响下丘脑-垂体-肾上腺系统(HPA系统)的功能基因多态性中，发现OPRM1 Asn40Asp、ACE I/D和ADEA2A C-1291G基因多态性与自杀有显著关联。对于功能磁共振成像，我们做了一个激活情绪的神经心理学任务。与情绪中性词相比，情绪负性词的再认在杏仁核和扣带回后部的激活更强。我们做的任务包括回忆过去的消极或积极的情节和想象未来的消极或积极的情节。激活部位主要在额叶内侧皮质、背外侧前额叶皮质、扣带回后部。

1. We studied the clinical and psychological characteristics associated with suicidality based on the history of lethal suicide attempt in 76 patients mainly with mood disorders. Hopelessness rather than depression, aggression in less than 40 years old patients and neuroticism were associated with suicidality. The perspectives on death were not associated with suicidality.2. We performed the profiling of mRNA expressions in amygdala of suicide brains. The 21 increased and the 9 decreased expressions of genes were identified. Among the genes with increased expressions, the polymorphisms of 14-3-3 ε gene were associated with suicide. Any polymorphisms in genes with the decreased expressions were not associated with suicide.3. Among the functional gene polymorphisms which affect a hypothalamic-pituitary-adrenal system (HPA system), we found the significant associations of OPRM1 Asn40Asp, ACE I/D and ADEA2A C-1291G polymorphism with suicide.4. For functional MRI, we made a neuropsychological task which activates emotion. A stronger activation in amygdala and posterior cingulate gyrus was shown in case of recognition in emotionally negative words, compared with emotionally neutral words. We made the tasks comprising the recall of past negative or positive episodes and the imagination of future negative or positive episodes. The activations were found in the medial frontal cortex, dorsolateral prefrontal cortex posterior cingulate gyrus.