Immobilisation stress induces a paradoxical sleep rebound in rat

Immobilisation stress induces a paradoxical sleep rebound in rat

Rampin C, Cespuglio R, Chastrette N, Jouvet M.

Département de Médecine Expérimentale, INSERM U 52, CNRS URA 1195, Université Claude Bernard, Lyons, France.

An immobilisation stress (IS) of 2 h applied to rats at the beginning of the dark period (12 h), i.e. when the animals are more active, induces during the 10 consecutive h a significant rebound (+92%) of paradoxical sleep (PS) while slow-wave sleep state (SWS) is poorly affected. Two h of sleep deprivation, also applied at the beginning of the dark period and realized either by the platform technique or by maintaining the animals awake with gentle handling, do not affect significantly subsequent SWS and PS. Finally, when repetitive IS are inflicted to the animals (one IS of 2 h every 3 days) an attenuation of the PS rebound is observed.

These data suggest that a qualitative aspect of the waking state as in an intense stressful situation might be the source of a hormonal process inducing a PS (paradoxical sleep) excess.

PMID: 1922920 [PubMed - indexed for MEDLINE]

http://www.ncbi.nlm.nih.gov/pubmed/1922920

Involvement of stress in the sleep rebound mechanism induced by sleep deprivation in the rat: use of alpha-helical CRH(9-41)

González, M M del C.; Valatx, J-L

Abstract

A previous study demonstrated the efficacy of the corticotropin-releasing hormone (CRH) receptor antagonist, [alpha] -helical CRH (9-41), in blocking the paradoxical sleep increase induced by stress.

In the present study, this peptide was used to evaluate the involvement of the stress component of the sleep deprivation, in the paradoxical sleep rebound.

Rats were subjected for 10 h to the classical water-tank sleep-deprivation technique and were given, every 2 h throughout the sleep deprivation period, intracerebroventricular injections of either 100 [micro]g/5 [micro]I of a-helical CRH (9-41) or vehicle alone.

Continuous recordings showed that antagonist treatment decreased the PS rebound, but not the SWS rebound, following sleep deprivation.

These findings suggest that, in the water-tank sleep deprivation method, stress, acting via CRH activation, is the main factor inducing the paradoxical sleep rebound.

(C) 1998 Lippincott Williams & Wilkins, Inc.

http://journals.lww.com/behaviouralpharm/Abstract/1998/12000/Involvement_of_stress_in_the_sleep_rebound.1.aspx