Plasma concentrations of melatonin in man following oral absorption of different preparations.

Aldhous, M.; Franey, Christine; Wright, John W.; Arendt, Joséphine

doi:10.1111/j.1365-2125.1985.tb02679.x

Cited by 169 publications

(93 citation statements)

References 10 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…One explanation for the lack of a clear dose-dependent effect is that both doses produce supraphysiological levels of circulating plasma melatonin shortly after ingestion that may be indistinguishable at a receptor level. Melatonin pharmacokinetics are known to vary greatly between individuals (Aldhous et al, 1985), and there may be individual differences in feedback of high circulating melatonin levels on the number and sensitivity of melatonin receptors (Gauer et al, 1993). Another question is whether the differences in period between individuals, and therefore the relative zeitgeber strength of melatonin required to entrain, determined whether entrainment occurred.…”

Section: Discussionmentioning

confidence: 99%

The Effects of Low-Dose 0.5-mg Melatonin on the Free-Running Circadian Rhythms of Blind Subjects

et al. 2003

View full text Add to dashboard Cite

Exogenous melatonin (0.5-10 mg) has been shown to entrain the freerunning circadian rhythms of some blind subjects. The aim of this study was to assess further the entraining effects of a daily dose of 0.5 mg melatonin on the cortisol rhythm and its acute effects on subjective sleep in blind subjects with free-running 6-sulphatoxymelatonin (aMT6s) rhythms (circadian period [τ] 24.23-24.95 h). Ten subjects (9 males) were studied, aged 32 to 65 years, with no conscious light perception (NPL). In a placebo-controlled, single-blind design, subjects received 0.5 mg melatonin or placebo p.o. daily at 2100 h (treatment duration 26-81 days depending on individuals' circadian period). Subjective sleep was assessed from daily sleep and nap diaries. Urinary cortisol and aMT6s were assessed for 24 to 48 h weekly and measured by radioimmunoassay. Seven subjects exhibited an entrained or shortened cortisol period during melatonin treatment. Of these, 4 subjects entrained with a period indistinguishable from 24 h, 2 subjects continued to free run for up to 25 days during melatonin treatment before their cortisol rhythm became entrained, and 1 subject appeared to exhibit a shortened cortisol period throughout melatonin treatment. The subjects who entrained within 7 days did so when melatonin treatment commenced in the phase advance portion of the melatonin PRC (CT6-18). When melatonin treatment ceased, cortisol and aMT6s rhythms free ran at a similar period to before treatment. Three subjects failed to entrain with initial melatonin treatment commencing in the phase delay portion of the PRC. During melatonin treatment, there was a significant increase in nighttime sleep duration and a reduction in the number and duration of daytime naps. The positive effect of melatonin on sleep may be partly due to its acute soporific properties. The findings demonstrate that a daily dose of 0.5 mg melatonin is effective at entraining the free-running circadian systems in most of the blind subjects studied, and that circadian time (CT) of administration of melatonin may be important in determining whether a subject entrains to melatonin treatment. Optimal treatment with melatonin for this non-24-h sleep disorder should correct the underlying circadian disorder (to entrain the sleep-wake cycle) in addition to improving sleep acutely.

show abstract

Section: Discussionmentioning

confidence: 99%

The Effects of Low-Dose 0.5-mg Melatonin on the Free-Running Circadian Rhythms of Blind Subjects

et al. 2003

View full text Add to dashboard Cite

show abstract

“…Melatonin, 200 ,ug was dissolved in 5 ml 2% ethanol and sunflower oil (for pharmacokinetic comparison with other preparations see Aldhous et al, 1985). Melatonin and placebo (vehicle only) were ingested with a glass of water.…”

Section: Study Bmentioning

confidence: 99%

Acute treatment with desipramine stimulates melatonin and 6‐sulphatoxy melatonin production in man.

Franey¹,

Aldhous²,

Burton³

et al. 1986

Brit J Clinical Pharma

Self Cite

View full text Add to dashboard Cite

Acute administration of the antidepressant drug desipramine (DMI) in man, increased evening melatonin secretion, which reached peak plasma levels 2‐4 h earlier than after placebo administration. The increase at set time points 21.00 h‐22.00 h was directly proportional to an individual's integrated night‐time secretion of melatonin. We have shown that this stimulation was not an effect of DMI inhibition on the hepatic metabolism of melatonin to 6‐sulphatoxy melatonin (aMT6s), indeed aMT6s is in itself a good index of the evening melatonin rise. The stimulation of early evening melatonin by DMI might be exploited as a simple pineal function test.

show abstract

“…The ingestion of 40-mg capsules is, in fact, known to result in plasma concentrations much above the physiological ones for more than 8 h (Waldhauser et al, 1984;Aldhous et al, 1985), and which have been associated with some biological activities, such as activation of some lymphocyte subsets in cancer patients .…”

Section: Discussionmentioning

confidence: 99%

Double-blind randomized study on the myeloprotective effect of melatonin in combination with carboplatin and etoposide in advanced lung cancer

et al. 1999

View full text Add to dashboard Cite

A significant myeloprotective effect of melatonin in mice treated with etoposide, cyclophosphamide or carboplatin has been reported. The present study was designed to evaluate if the same effect could be observed in patients receiving chemotherapy. Twenty previously untreated patients with inoperable lung cancer received two cycles of carboplatin (given at area under the curve 5 by the Calvert formula) on day 1 and etoposide (150 mg m −2 i.v.) on days 1–3 every 4 weeks. Melatonin 40 mg or placebo (double-blind) was given orally in the evening for 21 consecutive days, starting 2 days before chemotherapy. Patients were randomized to receive melatonin either with the first or the second cycle. Complete blood cell count with differential was done three times per week for 3 weeks. The median age of the cohort was 60 years (range 42–69), 16 patients had non-small cell and four patients small-cell lung cancer, 12 stage III and eight stage IV disease. In a multivariate analysis including age, sex, diagnosis, stage, performance status, doses of carboplatin and etoposide, and concomitant treatment with melatonin or placebo, the haematological parameters – depth and duration of toxicity for haemoglobin, platelets and neutrophils (ANC) – were not significantly different between cycles with/without melatonin. The mean ANC nadir and the mean number of days with ANC < 0.5 × 10 9 l −1 were 0.5 × 10 9 l −1 and 2.5 days, respectively, with/without melatonin. We concluded that, in patients with lung cancer, melatonin given orally at a dose of 40 mg per day for 21 days in the evening, does not protect against the myelotoxic effect of carboplatin and etoposide. © 1999 Cancer Research Campaign

show abstract

Plasma concentrations of melatonin in man following oral absorption of different preparations.

Cited by 169 publications

References 10 publications

The Effects of Low-Dose 0.5-mg Melatonin on the Free-Running Circadian Rhythms of Blind Subjects

The Effects of Low-Dose 0.5-mg Melatonin on the Free-Running Circadian Rhythms of Blind Subjects

Acute treatment with desipramine stimulates melatonin and 6‐sulphatoxy melatonin production in man.

Double-blind randomized study on the myeloprotective effect of melatonin in combination with carboplatin and etoposide in advanced lung cancer

Contact Info

Product

Resources

About