Mice convert melatonin to 6-sulphatoxymelatonin.

The principal objective of this study was to establish whether mice can convert melatonin to 6-sulphatoxymelatonin (aMT6s). Precision-cut liver slices from C3H/He, C57BL/6, and BALB/c mice were incubated with melatonin, and the concentration of aMT6s in the culture media was determined using a sensitive and specific radioimmunoassay procedure. All three strains of mice generated aMT6s in a time-dependent manner; no significant strain differences were observed.

Melatonin excretion in normal children and in tuberous sclerosis complex with sleep disorder responsive to melatonin.

To determine normal melatonin excretion patterns in healthy children without sleep disorder and to compare these with those of patients with tuberous sclerosis complex and sleep disorder responsive to exogenous melatonin, we measured 6-sulfatoxymelatonin excretion in 21 healthy children and in 7 patients with tuberous sclerosis complex and sleep disorder responsive to melatonin (a 5 mg oral dose increasing total sleep time). Total excretion, cosinor percentage, and acrophase time of 6-sulfatoxymelatonin excretion were estimated. In normal children, total 6-sulfatoxymelatonin excretion was range 11.

Four days of citalopram increase suppression of cortisol secretion by prednisolone in healthy volunteers.

Rationale: Chronic antidepressant treatment increases glucocorticoid-mediated negative feedback on the hypothalamic-pituitary-adrenal (HPA) axis, and thus reduces HPA axis activity, in depressed patients and healthy controls. In contrast, acute antidepressant treatment induces an activation of basal HPA axis activity.

Objectives: We examined the effects of 4 days of treatment with the selective serotonin reuptake inhibitor, citalopram, on basal salivary cortisol and on suppression of salivary cortisol by prednisolone.

Does melatonin improve sleep in older people? A randomised crossover trial.

Study Objective: to determine whether melatonin will improve quality of sleep in healthy older people with age-related sleep maintenance problems.

Design: a double blind randomised placebo controlled crossover trial in healthy older volunteers.

Setting: a largely urban population, Auckland, New Zealand.

The 3111 Clock gene polymorphism is not associated with sleep and circadian rhythmicity in phenotypically characterized human subjects.

Mutations in clock genes are associated with abnormal circadian parameters, including sleep. An association has been reported previously between a polymorphism (3111C), situated in the 3'-untranslated region (3'-UTR) of the circadian gene Clock and evening preference. In the present study, this polymorphism was assessed in: (1) 105 control subjects with defined diurnal preference, (2) 26 blind subjects with free-running circadian rhythms and characterized with regard to circadian period (tau) and (3) 16 delayed sleep phase syndrome patients.

Sulphatoxymelatonin excretion during opiate withdrawal: a preliminary study.

The excretion of sulphatoxymelatonin (aMT6S), a major metabolite of melatonin in urine, is dependent on noradrenergic (NA) neuronal activity within the pineal gland and thus represents a neuroendocrine marker of NA neuronal function. Many of the clinical features of opiate withdrawal result from increased firing of central NA neurones. In this study, we test the hypothesis that aMT6S excretion is increased during opiate withdrawal in opiate-dependent patients.

A novel prednisolone suppression test for the hypothalamic-pituitary-adrenal axis.

We have developed a suppressive test for the hypothalamic-pituitary-adrenal (HPA) axis using prednisolone, which is similar to endogenous glucocorticoids. We used a single-blind, repeated-measure design in healthy volunteers. In the first phase of the study, we compared placebo or prednisolone 2.