Linked Life Data

19874874

Source:http://linkedlifedata.com/resource/pubmed/id/19874874

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
2009-12-16
pubmed:abstractText
The present study was undertaken to investigate the influence of gonadotropin-releasing hormone (GnRH) and its agonist and antagonist on oxytocin (OT) release from the rat hypothalamo-neurohypophysial (H-N) system. An additional aim was to determine whether the possible response of oxytocinergic neurons to these peptides could be modified by melatonin through a cAMP-dependent mechanism. The results show that the highly selective GnRH agonist (i.e., [Des-Gly(10),d-His(Bzl)(6),Pro-NHEt(9)]-LHRH; Histrelin) stimulates the secretion of OT from an isolated rat H-N system. Melatonin significantly inhibited basal and histrelin-induced release of OT in vitro, and displayed no significant influence on OT release in the presence of GnRH or its antagonist. Addition of melatonin to a medium containing forskolin resulted in significant reduction of OT secretion from the H-N system. On the other hand, addition of forskolin to a medium containing both histrelin and melatonin did not further alter the inhibitory influence of melatonin on the histrelin-dependent secretion of OT in vitro. Intracerebroventricular (icv) infusion (experiment in vivo) of a GnRH antagonist resulted in substantial inhibition of OT release, thus revealing the stimulatory action of endogenous GnRH. In melatonin-treated animals, blood plasma OT levels were not changed in comparison to the vehicle. Our present data strongly suggests that activation of the GnRH receptor in the hypothalamus is involved in stimulation of OT secretion from the rat H-N system. It has also been shown, under experimental in vitro conditions, that melatonin fully suppresses the response of oxytocinergic neurons to the GnRH agonist - histrelin. The effect of melatonin on OT release is mediated by the cAMP-dependent mechanism, although other mechanisms of action are also possible.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jan
pubmed:issn
1873-2747
pubmed:author
pubmed:issnType
Electronic
pubmed:day
15
pubmed:volume
81
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
185-90
pubmed:meshHeading
pubmed:year
2010
pubmed:articleTitle
Hypothalamic gonadotropin-releasing hormone receptor activation stimulates oxytocin release from the rat hypothalamo-neurohypophysial system while melatonin inhibits this process.
pubmed:affiliation
Department of Pathophysiology, Medical University of Lodz, Narutowicza 60, str., 90-136 Lodz, Poland. marlena.juszczak@umed.lodz.pl
pubmed:publicationType
Journal Article, In Vitro, Research Support, Non-U.S. Gov't