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

A previous study demonstrated the efficacy of the corticotropin-releasing h ormone (CRH) receptor antagonist, ex-helical CRH (9-41), in blocking the pa radoxical sleep increase induced by stress. In the present study, this pept ide was used to evaluate the involvement of the stress component of the sle ep deprivation, in the paradoxical sleep rebound. Rats were subjected for 1 0 h to the classical water-tank sleep-deprivation technique and were given, every 2 h throughout the sleep deprivation period, inh intracerebroventric ular injections of either 100 mu g/5 mu l of alpha-helical CRH (9-41) or ve hicle alone. Continuous recordings showed that antagonist treatment decreas ed the PS rebound, but not the SWS rebound, following sleep deprivation. Th ese findings suggest that, in the,vater-tank sleep deprivation method, stre ss, acting via CRH activation, is the main factor inducing the paradoxical sleep rebound. Behav Pharmacol 1998; 9:655-662 (C) 1998 Lippincott Williams & Wilkins.