Cui H, Sakamoto H, Higashi S, Kawata M
Department of Anatomy and Neurobiology, Kyoto Prefectural University of Medicine, Kawaramachi Hirokoji, Kamigyo-ku, Kyoto 602-8566, Japan.
Neuroscience. 2008 Mar 27;152(3):703-12. doi: 10.1016/j.neuroscience.2007.12.028. Epub 2007 Dec 27.
The amygdala modulates memory consolidation with the storage of emotionally relevant information and plays a critical role in fear and anxiety. We examined changes in neuronal morphology and neurotransmitter content in the amygdala of rats exposed to a single prolonged stress (SPS) as a putative animal model for human post-traumatic stress disorder (PTSD). Rats were perfused 7 days after SPS, and intracellular injections of Lucifer Yellow were administered to neurons of the basolateral (BLA) and central amygdala (CeA) to analyze morphological changes at the cellular level. A significant increase of dendritic arborization in BLA pyramidal neurons was observed, but there was no effect on CeA neurons. Neuropeptide Y (NPY) was abundant in BLA under normal conditions. The local concentration and number of immunoreactive fibers of NPY in the BLA of SPS-exposed rats were increased compared with the control. No differences were observed in this regard in the CeA. Double immunostaining by fluorescence and electron microscopy revealed that NPY immunoreactive terminals were closely associated with calcium/calmodulin II-dependent protein kinase (CaMKII: a marker for pyramidal neurons)-positive neurons in the BLA, which were immunopositive to glucocorticoid receptor (GR) and mineralocorticoid receptor (MR). SPS had no significant effect on the expression of CaMKII and MR/GR expression in the BLA. Based on these findings, we suggest that changes in the morphology of pyramidal neurons in the BLA by SPS could be mediated through the enhancement of NPY functions, and this structural plasticity in the amygdala provides a cellular and molecular basis to understand for affective disorders.
杏仁核通过存储与情绪相关的信息来调节记忆巩固，在恐惧和焦虑中起关键作用。我们研究了暴露于单次长时间应激（SPS）的大鼠杏仁核中神经元形态和神经递质含量的变化，将其作为人类创伤后应激障碍（PTSD）的一种假定动物模型。SPS处理7天后对大鼠进行灌注，向基底外侧杏仁核（BLA）和中央杏仁核（CeA）的神经元内注射荧光黄以分析细胞水平的形态变化。观察到BLA锥体神经元的树突分支显著增加，但对CeA神经元没有影响。在正常条件下，神经肽Y（NPY）在BLA中含量丰富。与对照组相比，暴露于SPS的大鼠BLA中NPY免疫反应纤维的局部浓度和数量增加。在CeA方面未观察到差异。荧光和电子显微镜双重免疫染色显示，NPY免疫反应终末与BLA中钙/钙调蛋白II依赖性蛋白激酶（CaMKII：锥体神经元标志物）阳性神经元紧密相关，这些神经元对糖皮质激素受体（GR）和盐皮质激素受体（MR）呈免疫阳性。SPS对BLA中CaMKII以及MR/GR的表达没有显著影响。基于这些发现，我们认为SPS引起的BLA锥体神经元形态变化可能通过NPY功能增强介导，杏仁核中的这种结构可塑性为理解情感障碍提供了细胞和分子基础。
