Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
5
pubmed:dateCreated
2005-11-21
pubmed:abstractText
Although studies have reported the effects of the menstrual cycle on melatonin rhythmicity, none has investigated the effects of menopause on the melatonin rhythm. The circadian rhythm in melatonin and its relationship to subjective alertness was investigated in pre- and postmenopausal women under constant routine conditions (controlled posture, dim lighting, calorie intake, temperature, and prolonged wakefulness). Eleven healthy pre-menopausal (42+/-4 yr) and 10 postmenopausal women (55+/-2 yr) participated in the study. Salivary melatonin samples and subjective measures of alertness and sleepiness were assessed hourly during the 22 h constant routine protocol. Postmenopausal women had a significantly earlier melatonin acrophase (1.1+/-0.5 h clock time in decimal h; mean+/-SEM, p<0.05) compared to the pre-menopausal women (2.3+/-0.3 h). There was no significant difference between melatonin onset and amplitude between the pre-menopausal and postmenopausal women. Self-rated alertness declined in both study groups as the length of sleep deprivation increased. Melatonin onset preceded the onset of self-rated sleepiness in both groups. The time interval between melatonin onset and the onset of sleepiness and alertness offset was significantly greater in the postmenopausal women compared to the pre-menopausal women. In conclusion, under controlled experimental conditions the timing of the melatonin rhythm was advanced in postmenopausal women altering its phase relationship to subjective alertness and sleepiness.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:issn
0742-0528
pubmed:author
pubmed:issnType
Print
pubmed:volume
22
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
859-72
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
2005
pubmed:articleTitle
Effect of menopause on melatonin and alertness rhythms investigated in constant routine conditions.
pubmed:affiliation
Neuroendocrinology Group, School of Biomedical and Molecular Sciences, University of Surrey, Guildford, Surrey, England. j.walters@surrey.ac.uk
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't