Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
1984-7-17
pubmed:abstractText
Effects of ageing and mental condition on the nyctohemeral and seasonal rhythms of plasma melatonin in human subjects were investigated. Four groups of subjects were formed for a transverse study: 7 healthy young men (24 years), 6 elderly women, 6 elderly men and 6 elderly patients (2 men and 4 women) suffering from senile dementia (70-80 years). The subjects were synchronized. Blood samples were taken every 4 h during 24 h in January, March, June and October. In comparison to young men, the plasma levels of melatonin were markedly decreased (by about one half) in elderly subjects without any difference according to sex or mental condition. Nyctohemeral rhythms of the hormone were validated in all groups and at all sampling sessions. The nyctohemeral acrophases were remarkably stable (around 03.00 h) whatever the season, age or sex. A seasonal variation was found in all groups (except elderly women) with differences between young and elderly subjects: plasma melatonin levels were significantly lower in January than in June in young men, whereas in elderly subjects they were significantly lower in October than in January/March. No significant difference was observed in mesor, amplitude or acrophase of nyctohemeral and seasonal rhythms of plasma melatonin in patients with senile dementia when compared with healthy elderly subjects. The stability of the nyctohemeral peak time whatever the age group or season as opposed to the differences in the seasonal pattern of plasma melatonin according to the age groups raises the problems of both outdoor photoperiod and ageing in ruling the secretion of melatonin in man.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jun
pubmed:issn
0001-5598
pubmed:author
pubmed:issnType
Print
pubmed:volume
106
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
145-51
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1984
pubmed:articleTitle
Patterns of plasma melatonin with ageing and mental condition: stability of nyctohemeral rhythms and differences in seasonal variations.
pubmed:publicationType
Journal Article, Comparative Study, Research Support, Non-U.S. Gov't