levels are decreased following tryptophan ingestion False- they increase
production is decreased by beta blockers True
supplements increase core body temperature False - it reduces core temperature
given intravenously reduces prolactin levels False - it increases prolactin levels
production is increased by benzodiazepines False - its decreases production
phase shifts circadian rhythms True - it shifts the sleep cycle forward
is reported to 'deepen' sleep True.
exerts a hypnotic effect even if basal endogenous levels of melatonin are high False - they need to be low
affects alpha and beta waves on EEG True - reduces their amplitude
may induce sleep by thermoregulatory effects True.
Dawson, D, Encel, N. (1993) Melatonin and Sleep in Humans. J Pineal Res., 15 1-12.
Hajak, G et al (1991) The influence of intravenous L-Tryptophan on plasma melatonin and sleep in men. Pharmacopsychiat. 24, 17-20
Healy, D and Waterhouse, J.M. (1995) The Circadian system and the therapeutics of the affective disorders. Phamac.Ther., 65, 241-263.
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