Linked Life Data

9662716

Source:http://linkedlifedata.com/resource/pubmed/id/9662716

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
6
pubmed:dateCreated
1998-9-17
pubmed:abstractText
Administration of leptin during undernutrition improves reproductive function, but whether this occurs at the level of the brain, pituitary, or gonads is not yet clear. The present study tested the hypothesis that one important mechanism is the control of pulsatile gonadotropin-releasing hormone (GnRH) secretion. Our approach was to determine if leptin could prevent the marked suppression of pulsatile luteinizing hormone (LH) secretion which occurs during fasting. Leptin (3 micrograms/g i.p.; three times/48 h) or vehicle was administered during a 48-hour fast in adult ovariectomized and estrogen-treated ovariectomized rats (n = 5-7/group). LH was measured in blood samples collected every 6 min for 2 h before and after fasting. In vehicle-treated animals, plasma insulin and leptin levels decreased after fasting. As expected, the LH pulse frequency also decreased markedly. When circulating leptin remained artificially elevated during fasting, the suppression of LH pulse frequency did not occur. Leptin treatment maintained a high LH pulse frequency in the presence or absence of estrogen. The finding that leptin modulates LH pulse frequency indicates that this fat-derived hormone conveys information about nutrition to mechanisms which regulate pulsatile gonadotropin-releasing hormone secretion. Because this occurs in the absence of estrogen, the mechanism does not necessarily involve modulation of negative feedback.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jun
pubmed:issn
0028-3835
pubmed:author
pubmed:issnType
Print
pubmed:volume
67
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
370-6
pubmed:dateRevised
2011-11-17
pubmed:meshHeading
pubmed:year
1998
pubmed:articleTitle
Evidence for GnRH regulation by leptin: leptin administration prevents reduced pulsatile LH secretion during fasting.
pubmed:affiliation
Reproductive Sciences Program, University of Michigan, Ann Arbor 48109-0404, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.