1999 Fiscal Year Final Research Report Summary

Pathogenesis of sleep disorder after acute stress

Research Project

Project/Area Number	10670927
Research Category	Grant-in-Aid for Scientific Research (C)
Allocation Type	Single-year Grants
Section	一般
Research Field	Psychiatric science
Research Institution	Tokyo Metropolitan Organization of Medical Research (1999) Tokyo Institute of Psychiatry (1998)
Principal Investigator	YAMAMOTO Kenichi Tokyo Institute of Psychiatry, Research Scientist, 東京都精神医学総合研究所・副所長(参事研究員) (90125237)
Co-Investigator(Kenkyū-buntansha)	HOSINO Tadao Tokyo Institute of Psychiatry, Visiting Scientist, 東京都精神医学総合研究所, 客員研究員
Project Period (FY)	1998 – 1999
Keywords	Acute Stress / Sleep / Sleep Disorder / Clonidine / Central Noradrenergic System / Hyperarousal / Levomepromazine
Research Abstract	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.