The Priority Of Sleep And Innate Escape Behavior And The Underlying Mechanisms Of Their Regulations

Optimal choice of innate behaviors is critical for animal survival.The mechanisms underlying the behavior choices enabling animals to adapt to particular environmental and internal conditions remain poorly understood.Here we studied how sleep deprivation affects the priority between sleep and innate defensive response and the underlying mechanism.We reported that the mice under acute 8 hours of sleep deprivation showed an exuberated innate escape response and upregulation of c-fos expression in multiple wakefulness regulating brain areas.By comparison,adrenalectomized mice under the same sleep deprivation condition even displayed a more exaggerated escape response and those wake-regulating brain areas were more active.These results suggest acute sleep deprivation enhances innate escape response possibly by altering wake state without significantly causing anxiety.We also reported that the hypothalamic-pituitary-adrenal axis feedback under sleep deprivation prevents the exaggerated escape response through modulating wake-regulating brain areas.Taken together,our findings indicate that animal prioritizes defensive response over sleep need,and suggest that the negative feedback of HPA axis might prevent the exaggerated reactivity of innate defensive behavior.Moreover,identified brain areas in this study that were activated after sleep deprivation provide an insight into the neural mechanisms underlying the relationship between sleep and innate defensive behavior.