Interleukin-1 induces changes in sleep, brain temperature, and serotonergic metabolism.
Simultaneous recordings of sleep-wake activity and of serotonergic metabolism in the medial preoptic area were performed in freely moving rats after the intracerebroventricular injection of interleukin-1 (IL-1) at dark onset. IL-1 (2.5 ng) induced a biphasic increase in slow-wave sleep and an early increase in serotonergic metabolism starting 30 min postinjection. Phasic, state-specific changes (which have been described in spontaneous sleep) were superimposed on this tonic, overall increase in serotonergic metabolism. IL-1 (25 ng) induced an increase in wakefulness and a delayed increase in serotonergic metabolism, which started 120 min postinjection. This suggests that the time course of the serotonergic activation could play a role in mediating IL-1 effects on sleep. Both doses of IL-1 induced a similar and significant increase in brain cortical temperature, suggesting that IL-1 effects on sleep are not a secondary effect of the increase in cortical temperature and that the serotonergic system is not involved in IL-1-induced fever.
Gemma
C
C
Istituto di Fisiologia Umana II, Università degli Studi, Milan, Italy.
Imeri
L
L
de Simoni
M G
MG
Mancia
M
M
D000818:Animals; D001831:Body Temperature / Q000187:drug effects*; D001921:Brain / Q000187:drug effects*; D004305:Dose-Response Relationship, Drug; D005110:Extracellular Space / Q000378:metabolism; D006801:Humans; D006897:Hydroxyindoleacetic Acid / Q000378:metabolism; D007276:Injections, Intraventricular; D007375:Interleukin-1 / Q000494:pharmacology*; D008297:Male; D011301:Preoptic Area / Q000378:metabolism; D051381:Rats; D011994:Recombinant Proteins; D012701:Serotonin / Q000378:metabolism*; D012890:Sleep / Q000187:drug effects*; D014851:Wakefulness / Q000187:drug effects
D007375:Interleukin-1; D011994:Recombinant Proteins; D012701:Serotonin; D006897:Hydroxyindoleacetic Acid