高唤醒对创伤后应激障碍形成发展的影响及其神经机制

高唤醒是创伤后应激障碍(PTSD)的主要症状之一, 对创伤后应激障碍的形成与发展起核心作用。急性应激期产生的高唤醒可以预测其后PTSD的回避与麻木、再体验等症状的形成, 在创伤后早期, 降低唤醒程度可以减轻PTSD相关的症状表现。下丘脑-垂体-肾上腺轴异常变化会导致去甲肾上腺素(NE)、促肾上腺皮质激素释放因子(CRF)过度释放, 同时皮质醇(酮)水平下降, 这二者是高唤醒产生与维持的主要原因。另外, 5-羟色胺(5-HT)系统的高度激活也影响了高唤醒的形成。食欲素神经肽与NE、CRF与5-HT系统有密切的神经联系, 可能参与高唤醒的调节, 是近年来研究的一个热点。

The Neural Mechanism Underlying Hyperarousal and Its Role in the Development of Posttraumatic Stress Disorder

Hyperarousal represents the core symptoms of posttraumatic stress disorder (PTSD) and plays a significant role in the development of PTSD. Peri-traumatic hyperarousal response predicts the occurrence of the PTSD symptoms like re-experience, avoidance and numbing, and attenuating the magnitude of the arousal response during peri-traumatic period can reduce the risk to develop PTSD symptom. Dysfunction of hypothalamic–pituitary–adrenal axis characterized with over-release of norepinephrine (NE) and corticotropin-releasing factor (CRF), but lack of cortisol or corticosterone is one of the most important neural mechanisms which cause and maintain the long-term hyperarousal state. Over-activation of serotonin (5-HT) system is also related to the hyperarousal situation after the traumatic experience. Recently, the role of orexin system in hypothalamus in hyperaroual or stress has attracted a lot of attention, because the orexin system is closely connected with NE, CRF and 5-HT system and it is vital in sleep and arousal transition.