Linked Life Data

7523206

Source:http://linkedlifedata.com/resource/pubmed/id/7523206

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1-2
pubmed:dateCreated
1994-11-1
pubmed:abstractText
Using a transgenic mouse derived GnRH expressing neuronal cell line, GT1-3, we studied the effects of activation of cAMP, Ca2+ and protein kinase C pathways by forskolin, ionomycin and the phorbol ester phorbol 12-myristate 13-acetate (PMA), respectively, upon gonadotropin-releasing hormone (GnRH) secretion, cellular peptide content, mRNA and RNA primary transcript levels. Forskolin, ionomycin and phorbol ester all caused an increase in GnRH secretion in GT1-3 cells in a time and dose-dependent manner during a short-term (1 h) static incubation. Prolonged treatment with forskolin (10 microM), ionomycin (1 microM) and PMA (10 nM) for 12 or 24 h resulted in significant decreases in GnRH mRNA levels. Time-course studies showed that the increases in GnRH secretion stimulated by forskolin, ionomycin and PMA were gradually attenuated over time in parallel with the decreases in mRNA expression. In contrast, there were only small and variable changes in the GnRH cellular content. Studies using a GnRH antagonist (100 microM) suggested that the released GnRH has a negative feedback effect on its own secretion. However, co-incubation with the GnRH antagonist did not alter the inhibitory effects on GnRH mRNA levels by the secretagogues. Further studies on the transcriptional effects of forskolin, ionomycin and PMA on GnRH gene expression in GT1-3 cells revealed that all three secretagogues suppressed GnRH RNA primary transcript levels, with forskolin having a slower time course of action. Thus, the inhibition of cytoplasmic GnRH mRNA, and presumably its synthesis, after 12-24 h of secretagogue treatment may be due at least in part to a suppression of GnRH gene transcription.(ABSTRACT TRUNCATED AT 250 WORDS)
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jun
pubmed:issn
0303-7207
pubmed:author
pubmed:issnType
Print
pubmed:volume
102
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
85-92
pubmed:dateRevised
2007-11-15
pubmed:meshHeading
pubmed:year
1994
pubmed:articleTitle
Second messenger regulation of mouse gonadotropin-releasing hormone gene expression in immortalized mouse hypothalamic GT1-3 cells.
pubmed:affiliation
Dr. Arthur M. Fishberg Research Center for Neurobiology, Mount Sinai School of Medicine, New York, NY 10029.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't