Intracerebroventricular injection of erythropoietin enhances sleep in the rat.
Systemic injection of erythropoietin (EPO) over several days reduces sleep fragmentation in patients with periodic limb movements in sleep (PLMS). However, there are no studies concerning the effects of EPO on spontaneous sleep. In this study, we determined the effects of intracerebroventricular (i.c.v.) administration of EPO on spontaneous rat sleep. Three doses of EPO (25, 75, and 125 ng) were injected i.c.v. at the onset of the dark period. All doses of EPO increased non-rapid eye movement sleep (NREMS). In addition, high and low doses of EPO (125 and 25 ng) increased rapid eye movement sleep (REMS), but the medium dose of EPO (75 ng) inhibited REMS. Electroencephalogram slow-wave activity during NREMS also increased following the two higher doses of EPO. In contrast, EPO injection during the light period failed to affect sleep. Brain temperature (Tbr) was not affected by any dose of EPO. These results suggest that EPO could be part of the cytokine network involved in sleep regulation.
D000818:Animals; D001921:Brain / Q000187:drug effects / Q000378:metabolism*; D002940:Circadian Rhythm / Q000187:drug effects / Q000502:physiology*; D016207:Cytokines / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D004921:Erythropoietin / Q000378:metabolism* / Q000494:pharmacology; D007276:Injections, Intraventricular; D008297:Male; D010775:Photic Stimulation; D051381:Rats; D017207:Rats, Sprague-Dawley; D017467:Receptors, Erythropoietin / Q000187:drug effects / Q000378:metabolism; D012890:Sleep / Q000187:drug effects / Q000502:physiology*; D020178:Sleep Disorders, Circadian Rhythm / Q000188:drug therapy / Q000378:metabolism / Q000503:physiopathology; D012893:Sleep Wake Disorders / Q000188:drug therapy / Q000378:metabolism* / Q000503:physiopathology; D012895:Sleep, REM / Q000187:drug effects / Q000502:physiology
D016207:Cytokines; D017467:Receptors, Erythropoietin; D004921:Erythropoietin