Pathogenesis of sleep disorder after acute stress

急性足部电击应激可引起睡眠-觉醒周期的三相改变。阶段1：压力过后立即失眠。阶段2：在阶段1之后持续几个小时的过度睡眠。阶段3：在压力的第二天过度觉醒。当通过左旋美普拉嗪(LP)诱导的睡眠来评估时，3相的高度觉醒变得更加明显。应激后第二天，注射LP至入睡的睡眠潜伏期延长，注射后40min的睡眠百分比下降。可乐定可抑制应激过程中去甲肾上腺素能的过度活动，从而防止这种LP诱导的睡眠障碍。这些结果表明，3相高觉醒的发病机制是由应激过程中去甲肾上腺素能神经元的过度活动所介导的。

Acute foot-shock stress could induce three-phase change in sleep-wake cycle. Phase 1: Insomnia immediately after the stress. Phase 2: Hypersomnia for several hours following the phase 1. Phase 3: Hyperarousalness on the following day of the stress. Hyperarousalness of the phase 3 becomes more evident when assessed by levomepronazin(Lp)-induced sleep. On the day following the stress, sleep latency from the injection of Lp to sleep onset became longer and sleep percentage during 40min after the injection decreased. This disturbance of Lp-induced sleep could be prevented by clonidine pretreatment, which suppress noradrenergic hyperactivity during the stress. These findings suggest that the pathogenesis of the phase 3 hyperarousalness is mediated by hyperactivity of noradrengergic neuron during the stress.