[Induction of paradoxical sleep (PS) by infusion of cerebrospinal fluid from PS-deprived rats].

In the rat, alpha-Methyldopa (alpha-MD, 50 mg/kg i.p.) induced during 8 hrs. an important reduction of paradoxical sleep (PS) and an increase of light slow waves sleep (SWS1). These effects were reversed by intraventricular infusion of cerebrospinal fluid (CSF) from PS-deprived donor rats, and PS restauration depended directly on the duration of the deprivation in the donor. It is probable that hypnogenic substances accumulate in the CSF during PS-deprivation, and that these factors can by-pass the noradrenergic step in the chain of biochemical events normally leading to the appearance of PS.