Functional significance of nociceptive amygdala in pain-induced negative emotion

脊髓背角中的大多数伤害性感受特异性投射神经元投射到臂旁外侧核（LPB），臂旁外侧核又投射到中央杏仁核（CeC）的囊部，形成了伤害性感受和情绪之间直接联系的解剖学基础。本研究的目的是确定在慢性疼痛模型中增强的LPB-CeC传递的机制和生理意义。我们分析了LPB-CeC传输以及其他杏仁核亚核内的急性制备的脑切片制备的神经病理性疼痛模型脊神经结扎和链脲佐菌素诱导的糖尿病。在不同的释放概率的单囊泡的内容，单纤维释放和振幅波动的估计明确地表明，释放站点的数量增加，允许多个囊泡被释放在同步增强突触从单纤维终端。这些结果表明慢性神经病理性疼痛中杏仁核突触具有特殊的结构可塑性和巩固性，这将为伤害性感受与负性情绪之间的联系增强提供依据。

The majority of nociception-specific projecting neurons in the spinal dorsal horn project to the lateral parabrachial nucleus(LPB) that in turn project to the capsular part of the central amygdala(CeC), forming an anatomical basis for direct link between nociception and emotion. The aim of this study was to identify the mechanism and physiological significance of the potentiated LPB-CeC transmission in chronic pain models. We analyzed the LPB-CeC transmission as well as those within other amygdaloid subnuclei in acutely prepared brain slices prepared from neuropathic pain models by spinal nerve ligation and streptozocin-induced diabetics. Estimation of mono-vesicular content, single fiber release and amplitude fluctuation at different release probabilities unequivocally demonstrated an increased number of release sites allowing multiple vesicles to be released in synchrony from single fiber terminals in potentiated synapses. These results point to a specific structural plasticity and its consolidation in the amygdala synapses in the chronic neuropathic pain, which would provide basis for the enhanced link between nociception and negative emotion.