Linked Life Data

2541362

Source:http://linkedlifedata.com/resource/pubmed/id/2541362

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
4
pubmed:dateCreated
1989-6-19
pubmed:abstractText
In order to evaluate the involvement of gonadotropin-releasing hormone (GnRH) in the effects of neuroexcitatory amino acids on luteinizing hormone (LH) secretion, N-methyl-D,L-aspartate (NMDA; 30 mg/kg s.c.) was administered to 50-day-old male rats. The in vitro release of GnRH from the hypothalamus showed a maximal increase (4.6-fold) in animals sacrificed 7.5 min after NMDA injection, while serum LH levels rose concomitantly. Incubation of rat hypothalami in vitro with kainate or NMDA concentrations greater than 0.1 mM resulted in a dose-related release of GnRH, NMDA being twofold more potent than kainate. Quisqualate (10 mM) did not affect the release of GnRH. On a molar basis, quinolinate (50 mM), a possible endogenous ligand for NMDA receptors, was the most effective in inducing GnRH secretion (34.9 +/- 4.9 pg/7.5 min, mean increment +/- SEM, n = 10). The effects of kainate and NMDA were mediated through different types of receptors, since GnRH response to kainate was unchanged in the absence of glycine or in the presence of increased concentrations of Mg2+ (2 mM) or Ca2+ (5.8 mM). In contrast, the GnRH response to NMDA was reduced by Ca2+ (5.8 mM) and abolished in the absence of glycine or in the presence of Mg2+ (2 mM). In addition, D,L-amino-5-phosphonopentanoic acid (AP5), a competitive antagonist of NMDA receptors, prevented the NMDA-induced release of GnRH. The permissive effect of glycine on GnRH response to NMDA was 2.7-fold more important using glycine concentrations of 0.01 microM than when concentrations greater than or equal to 100 microM were used.(ABSTRACT TRUNCATED AT 250 WORDS)
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Apr
pubmed:issn
0028-3835
pubmed:author
pubmed:issnType
Print
pubmed:volume
49
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
402-8
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1989
pubmed:articleTitle
Direct activation of gonadotropin-releasing hormone secretion through different receptors to neuroexcitatory amino acids.
pubmed:affiliation
Department of Pediatric, University of Liège, Belgium.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't