Effects induced by the electrical stimulation of the nucleus raphe dorsalis upon hypothalamic release of 5-hydroxyindole compounds and sleep parameters in the rat.
Electrical stimulation (30 min; pulse 0.5 ms, 150 microA, 20 Hz) of the antero-dorsal part of the nucleus raphe dorsalis (n.RD) induces in the basal hypothalamus (n. arcuate and surrounding areas) a large axonal release of 5-hydroxyindole compounds (5-OHLes; about +300%) measured by means of voltammetric technique. During such a release, evidence for a direct detection of serotonin (5-HT) is reported. The above stimulation induces also marked aversive behaviors together with prolonged polygraphic arousal. Three hours later, a significant paradoxical sleep (PS) rebound occurs. Both the 5-OHLes release and the PS rebound observed after n.RD stimulation are suppressed by a p-chlorophenylalanine (PCPA) pretreatment of the animals. The 5-HT-hypnogenic factor dependence of the PS rebound observed after n.RD stimulation is discussed.
Houdouin
F
F
Département de Médecine Expérimentale, INSERM U52-CNRS UA 1195, Université Cl. Bernard, Lyon, France.
Cespuglio
R
R
Jouvet
M
M
D000818:Animals; D004558:Electric Stimulation; D010134:Fenclonine / Q000494:pharmacology; D007031:Hypothalamus / Q000187:drug effects / Q000502:physiology*; D007211:Indoles / Q000378:metabolism*; D008297:Male; D010293:Pargyline / Q000494:pharmacology; D011903:Raphe Nuclei / Q000502:physiology*; D051381:Rats; D011919:Rats, Inbred Strains; D012701:Serotonin / Q000378:metabolism*; D012890:Sleep / Q000502:physiology*; D012895:Sleep, REM / Q000502:physiology; D014851:Wakefulness
D007211:Indoles; D012701:Serotonin; D010293:Pargyline; D010134:Fenclonine