Reaction of sleep-wakefulness cycle to stress is related to differences in hypothalamo-pituitary-adrenal axis reactivity in rat
Brain Research. 1998-08-01; 804(1): 114-124
DOI: 10.1016/S0006-8993(98)00670-2
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1. Brain Res. 1998 Aug 31;804(1):114-24. doi: 10.1016/s0006-8993(98)00670-2.
Reaction of sleep-wakefulness cycle to stress is related to differences in
hypothalamo-pituitary-adrenal axis reactivity in rat.
Bouyer JJ(1), Vallée M, Deminière JM, Le Moal M, Mayo W.
Author information:
(1)Laboratoire de Psychobiologie des Comportements Adaptatifs, INSERM U. 259,
Université de Bordeaux II, Domaine de Carreire, rue Camille Saint-Saëns, 33077,
Bordeaux Cedex, France.
Acute stress is known to modify sleep-wakefulness cycle, although with
considerable interindividual differences. The origin of these individual
differences remains unknown. One possibility is an involvement of the
hypothalamo-pituitary-adrenal axis (HPA), as its reactivity is correlated with
an individual’s behavioral reactivity to stress, and it is known to influence
the sleep-wakefulness cycle. The present study was designed to analyze
relationships between natural differences in behavioral reactivity to stress
associated with differential HPA reactivity and stress-induced changes in
sleep-wakefulness. Adult rats were classified into two sub-groups according to
their locomotor reactivity to a mild stress (novel environment): the ‘low
responders (LR)’ and the ‘high responders (HR)’ animals exhibited different
glucocorticoid secretion in response to stress. We show that immobilization
stress induced an increase in wakefulness in LR animals and a decrease in
wakefulness in HR animals. On the other hand, paradoxical sleep was increased in
both LR and HR animals. Moreover, we observed that LR animals slept more than
the HR animals, whereas the two groups had similar levels of paradoxical sleep.
These results indicate that the response of the sleep-wakefulness cycle to
stress is related to the behavioral reactivity to stress, in turn governed by
the individual’s reactivity of the HPA axis. The involvement of dopaminergic
mechanisms is discussed.
Copyright 1998 Elsevier Science B.V.