Linked Life Data

8609592

Source:http://linkedlifedata.com/resource/pubmed/id/8609592

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
1996-5-30
pubmed:abstractText
Photic regulation of the pineal melatonin synthesis was studied in 3- to 21-day-old rat pups by exposing the animals to light at night (30-40 min) or to darkness during the day (30-240 min). The pineal melatonin contents were measured by radioimmunoassay. A significant day/night difference in the melatonin content and the nocturnal light-induced decrease were not found until second postnatal week. A novel finding was that at the age of 13-17 days a daytime dark exposure elevated the pineal melatonin content; it was twofold as compared with the normal daytime level and about half of the nocturnal peak level. In 21-day-old rats the response had disappeared, while the nocturnal suppression by light persisted. The dark-induced increase of the melatonin synthesis was independent of the opening of the eyelids which occurs in pups at the age of two weeks, but it was greater in maternally isolated than non-isolated pups. The results suggest that one component of the circadian regulatory system matures at the end of the third postnatal week. This mechanism inhibits the elevation of the melatonin synthesis by darkness during the daytime.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Aug
pubmed:issn
0742-3098
pubmed:author
pubmed:issnType
Print
pubmed:volume
19
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
23-30
pubmed:dateRevised
2003-11-14
pubmed:meshHeading
pubmed:year
1995
pubmed:articleTitle
Daytime dark exposure increases pineal melatonin in rat pups.
pubmed:affiliation
Department of Physiology, University of Helsinki, Finland.
pubmed:publicationType
Journal Article