The present study was conducted to assess hypnotic action, effects on rectal temperature and dose dependency by daytime administration of exogenous melatonin (MLT) at 1 mg, 3 mg or 6 mg to subjects consisting of seven healthy juvenile adults. As a result, exogenous MLT significantly increased total sleep time and sleep efficiency, and MLT 6mg was observed to demonstrate hypnotic effects that were nearly equal to those of triazolam at 0.125 mg. Rectal temperature was significantly decreased at MLT 1mg and 3 mg, there were no significant differences observed in the hypothermic effects at MLT 6mg. These results indicate that exogenous MLT had dose-dependent hypnotic action on daytime sleep, and it is possible to consider that this hypnotic action was based on a direct-acting mechanism.
Sette giovani adulti sono stati trattati con melatonina a vari dosaggi (1, 3 e 6 mg); si osserva aumento del tempo totale di sonno e della efficienza del sonno. La melatonina 6 mg ha un'efficacia simile al triazolam (0,125 mg). L'effetto ipotermico della melatonina (temperatura rettale) è presente a tutti i dosaggi. Complessivamente la melatonina esogena ha dimostrato un'azione ipnotica dose-dipendente su sonno di giorno (la melatonina era somministrata di giorno) per un effetto diretto sui centri del sonno.