Laboratório de Biologia Celular e Tecidual, Escola de Ciências, Pontifícia Universidade Católica do Rio Grande do Sul (PUCRS), Av. Ipiranga 6681, Prédio 12C, Sala 104, Porto Alegre, Rio Grande do Sul, CEP 90619-900, Brazil.
Programa de Pós-Graduação em Biologia Celular e Molecular, Pontifícia Universidade Católica do Rio Grande do Sul (PUCRS), Porto Alegre, Rio Grande do Sul, Brazil.
Brain Struct Funct. 2019 Nov;224(8):2857-2870. doi: 10.1007/s00429-019-01943-4. Epub 2019 Aug 22.
Imaging studies have shown abnormal amygdala function in patients with posttraumatic stress disorder (PTSD). In addition, alterations in synaptic plasticity have been associated with psychiatric disorders and previous reports have indicated alterations in the amygdala morphology, especially in basolateral (BLA) neurons, are associated with stress-related disorders. Since, some individuals exposed to a traumatic event develop PTSD, the goals of this study were to evaluate the early effects of PTSD on amygdala glucose metabolism and analyze the possible BLA dendritic spine plasticity in animals with different levels of behavioral response. We employed the inescapable footshock protocol as an experimental model of PTSD and the animals were classified according to the duration of their freezing behavior into distinct groups: "extreme behavioral response" (EBR) and "minimal behavioral response". We evaluated the amygdala glucose metabolism at baseline (before the stress protocol) and immediately after the situational reminder using the microPET and the radiopharmaceutical F-FDG. The BLA dendritic spines were analyzed according to their number, density, shape and morphometric parameters. Our results show the EBR animals exhibited longer freezing behavior and increased proximal dendritic spines density in the BLA neurons. Neither the amygdaloid glucose metabolism, the types of dendritic spines nor their morphometric parameters showed statistically significant differences. The extreme behavior response induced by this PTSD protocol produces an early increase in BLA spine density, which is unassociated with either additional changes in the shape of spines or metabolic changes in the whole amygdala of Wistar rats.
影像学研究表明，创伤后应激障碍（PTSD）患者的杏仁核功能异常。此外，突触可塑性的改变与精神疾病有关，先前的报告表明，杏仁核形态的改变，特别是基底外侧（BLA）神经元的改变，与应激相关障碍有关。由于一些暴露于创伤性事件的个体发展为 PTSD，因此本研究的目的是评估 PTSD 对杏仁核葡萄糖代谢的早期影响，并分析具有不同行为反应水平的动物中 BLA 树突棘可塑性的可能变化。我们采用不可逃避的足底电击方案作为 PTSD 的实验模型，根据动物的冻结行为持续时间将其分为不同的组：“极端行为反应”（EBR）和“最小行为反应”。我们在基线（应激方案之前）和情境提醒后立即使用 microPET 和放射性药物 F-FDG 评估杏仁核葡萄糖代谢。根据 BLA 神经元的数量、密度、形状和形态计量学参数分析树突棘。我们的结果表明，EBR 动物表现出更长的冻结行为和 BLA 神经元中近端树突棘密度增加。杏仁核葡萄糖代谢、树突棘类型及其形态计量学参数均无统计学差异。这种 PTSD 方案引起的极端行为反应导致 BLA 棘密度的早期增加，这与棘的形状的其他变化或 Wistar 大鼠整个杏仁核的代谢变化无关。
