Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
1989-8-2
pubmed:abstractText
The hypothesis that neuropeptide-Y (NPY) suppresses pulsatile LH secretion in ovariectomized (OVX) rats was examined. Rats were bilaterally OVX and 6 weeks (Exp 1) or 2 weeks (Exp 2) later a stainless steel cannula was implanted in the third cerebral ventricle (3V). Seven to 10 days later, an intraatrial cannula was inserted. The next day, a blood sample was withdrawn, and each conscious unrestrained animal received a 3V injection of synthetic porcine NPY (5 or 0.5 micrograms/2 microliters saline) or vehicle in Exp 1. Blood samples were taken every 10 min for 2 h and centrifuged, and the plasma was analyzed for LH by RIA. In Exp 2, OVX rats received a 3V injection of NPY (5 micrograms/2 microliters) or vehicle. Blood samples were taken before and 60 min after injection. At 60 min, LHRH (10 ng/100 g BW) was injected iv, and blood was withdrawn 10, 20, 60, and 120 min later. NPY caused a dramatic dose-related reduction in the pulsatile release of LH compared to that in vehicle-treated rats. The 5.0-micrograms dose of NPY significantly reduced LH pulse frequency (P less than 0.05), pulse amplitude (P less than 0.01), and trough levels (P less than 0.01) compared to those in saline-injected controls. The lower dose of NPY (0.5 micrograms) significantly decreased the mean LH levels throughout the 2-h sampling period and slightly, though not significantly, the pulse frequency. Administration of LHRH increased plasma LH levels by 124% in control animals and by 1239% in NPY-injected rats. The results of these studies indicate that the suppressive effects of NPY on pulsatile LH release appear to be exerted through inhibition of pulsatile LHRH secretion from the hypothalamus.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
AIM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jul
pubmed:issn
0013-7227
pubmed:author
pubmed:issnType
Print
pubmed:volume
125
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
186-91
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1989
pubmed:articleTitle
Neuropeptide-Y suppresses pulsatile secretion of luteinizing hormone in ovariectomized rats: possible site of action.
pubmed:affiliation
Department of Anatomy and Cell Biology, Emory University School of Medicine, Atlanta, Georgia 30322.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't