Effects of melatonin on sleep and neurochemistry in the rat.
1 The effects of intraperitoneally administered melatonin on sleep and brain neurochemistry in the rat were studied by use of EEG recording and standard fluorescence techniques. 2 Melatonin, 10 mg/kg, reduced time to sleep onset and time spent awake but increased both slow wave and paradoxical sleep. Qualitatively similar but smaller effects were produced by a dose of 2.5 mg/kg. 3 Neither dose of melatonin altered normal EEG patterns or disrupted normal sleep behaviour. 4 Melatonin, 20 mg/Kg, did not significantly alter concentrations of tryptophan, 5-hydroxytryptamine, 5-hydroxyindoleacetic acid, noradrenaline or dopamine in any part of the brain. 5 it is concluded that the sleep promoting activity of melatonin cannot be related to gross changes in brain indoleamine and catecholamine levels.
D000818:Animals; D001679:Biogenic Amines / Q000378:metabolism; D001923:Brain Chemistry / Q000187:drug effects*; D002395:Catecholamines / Q000378:metabolism; D004298:Dopamine / Q000378:metabolism; D004569:Electroencephalography; D007211:Indoles / Q000378:metabolism*; D008297:Male; D008550:Melatonin / Q000494:pharmacology*; D009638:Norepinephrine / Q000378:metabolism; D051381:Rats; D011919:Rats, Inbred Strains; D012890:Sleep / Q000187:drug effects*
D001679:Biogenic Amines; D002395:Catecholamines; D007211:Indoles; D008550:Melatonin; D004298:Dopamine; D009638:Norepinephrine