Linked Life Data

3921070

Source:http://linkedlifedata.com/resource/pubmed/id/3921070

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
1985-6-12
pubmed:abstractText
Daily rhythms of luteinizing hormone (LH) and follicle-stimulating hormone (FSH) are measurable in the serum of prepubertal female golden hamsters by 17 days after birth. These rhythms, which are characterized by peak levels at 1700 h, persist until they are replaced by a 4-day rhythm as ovulatory cycles begin, approximately 3 wk later. We have tested the proposition that the ovaries are required for the onset and maintenance of clock-timed gonadotropin release by removing the ovaries and measuring the levels of LH and FSH in prepubertal hamsters. Ovariectomy was performed both before and after the onset of the rhythm and the effect of removal was determined by subsequent collection of blood samples during the mid- to late-prepubertal period. Ovariectomy on 7, 10 or 13 days after birth results in tonic levels of LH and FSH in blood samples collected at 1400, 1700 and 2000 h on Days 17 through 29. Sham-operated or intact controls had significantly elevated levels of these hormones at 1700 h. Ovariectomy on Day 21 and killing on Day 25 at the same times of day abolished the rhythm of serum LH measured in sham-ovariectomized controls. Ovariectomy on Day 21 and killing on Days 26, 28 or 30 at hourly intervals resulted in variable but nonrhythmic patterns of circulating LH. Thus, ovariectomy before the initiation of clock-timed gonadotropin release prevented its initiation; ovariectomy after its initiation abolished the rhythm. These results show that the ovary provides an essential "message" to the brain-pituitary axis for the initiation and maintenance of clock-timed gonadotropin release in prepubertal females.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Mar
pubmed:issn
0006-3363
pubmed:author
pubmed:issnType
Print
pubmed:volume
32
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
284-9
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1985
pubmed:articleTitle
Effects of ovariectomy on clock-timed daily gonadotropin rhythms in prepubertal golden hamsters.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, U.S. Gov't, Non-P.H.S.