5-Methoxypsoralen: effect on the noradrenaline circadian rhythm of sleep-deprived subjects.
5-methoxypsoralen (5-MOP), a serotonin analogue, stimulates the secretion of melatonin, which plays an important role in circadian rhythm regulation. Melatonin production is essentially controlled by noradrenaline (NA). To investigate the effect of 5-MOP on the 24 hr NA rhythm, hourly plasma NA concentrations measured over 24 hr in 7 healthy young subjects who took 40 mg 5-MOP orally at 21:00 hr the evening before were compared with values obtained in drug-free subjects. All subjects were sleep-deprived and under conditions in which sympathetic nervous system activation was repeated every hour over 24 hr. In both series of patients, a significant difference was observed between mean morning values and mean night values, reflecting persistence of a circadian rhythm. In subjects given 5-MOP, a significant difference was also observed between mean afternoon values and mean night values. However, MANOVA analysis failed to find any difference between the two series of subjects. Acute administration of 5-MOP thus had no significant effect on the NA circadian rhythm under our study conditions.
Candito
M
M
Laboratoire de Biochimie, Hôpital Pasteur, Nice, France.
Pringuey
D
D
Lehert
P
P
Drici
M
M
Souêtre
E
E
Chambon
P
P
Darcourt
G
G
D000078223:5-Methoxypsoralen; D000284:Administration, Oral; D000328:Adult; D002940:Circadian Rhythm / Q000187:drug effects* / Q000502:physiology; D006801:Humans; D008297:Male; D008730:Methoxsalen / Q000031:analogs & derivatives* / Q000494:pharmacology; D009638:Norepinephrine / Q000097:blood*; D012892:Sleep Deprivation / Q000502:physiology*
D000078223:5-Methoxypsoralen; D008730:Methoxsalen; D009638:Norepinephrine