Linked Life Data

11115775

Source:http://linkedlifedata.com/resource/pubmed/id/11115775

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
2001-1-30
pubmed:abstractText
Leptin, the adipocyte-produced hormone that plays a key role in body weight homeostasis, has recently been found to be involved in the regulation of the hypothalamic-pituitary-adrenal axis. Moreover, reciprocal interactions between leptin and glucocorticoids have been described. In the present communication, two different strategies were undertaken to explore the mode of action of leptin in the direct control of rat adrenal function. First, a synthetic peptide approach demonstrated that the inhibitory effect of leptin on basal and ACTH-stimulated corticosterone secretion in vitro is, at least partially, mapped to a domain of the native protein between amino acids 116 and 130, i.e. an area of the molecule also relevant in terms of regulation of food intake and endocrine control. Secondly, semi-quantitative RT-PCR analysis indicated a complex pattern of adrenal leptin receptor (Ob-R) mRNA expression, with predominant expression of the Ob-Ra and Ob-Rb isoforms, as well as moderate levels of the Ob-Rc and Ob-Rf variants, whereas negligible signals for the Ob-Re isoform were detected. Interestingly, such an expression pattern appeared hormonally regulated as exposure to human recombinant leptin (10(-7 )M) or ACTH (10(-7 )M) significantly decreased Ob-R isoform mRNA expression. Indeed, dose-dependent ligand-induced Ob-Ra and Ob-Rb mRNA down-regulation was further confirmed by adrenal stimulation with increasing concentrations (10(-9)-10(-5 )M) of the active leptin fragment, leptin 116-130 amide. Overall, our results provide evidence for a novel regulatory step at the level of Ob-R mRNA expression in the interplay between ACTH and leptin for the tuning of rat adrenal corticosterone secretion. Furthermore, our data showing down-regulation of Ob-R mRNA expression by its cognate ligand may well be relevant to leptin physiology and its alteration in various disease states.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Dec
pubmed:issn
0022-0795
pubmed:author
pubmed:issnType
Print
pubmed:volume
167
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
479-86
pubmed:dateRevised
2007-11-15
pubmed:meshHeading
pubmed-meshheading:11115775-Adrenal Glands, pubmed-meshheading:11115775-Adrenocorticotropic Hormone, pubmed-meshheading:11115775-Analysis of Variance, pubmed-meshheading:11115775-Animals, pubmed-meshheading:11115775-Carrier Proteins, pubmed-meshheading:11115775-Corticosterone, pubmed-meshheading:11115775-Depression, Chemical, pubmed-meshheading:11115775-Gene Expression Regulation, pubmed-meshheading:11115775-Humans, pubmed-meshheading:11115775-Male, pubmed-meshheading:11115775-Organ Culture Techniques, pubmed-meshheading:11115775-Peptide Fragments, pubmed-meshheading:11115775-Protein Isoforms, pubmed-meshheading:11115775-RNA, Messenger, pubmed-meshheading:11115775-Rats, pubmed-meshheading:11115775-Rats, Wistar, pubmed-meshheading:11115775-Receptors, Cell Surface, pubmed-meshheading:11115775-Receptors, Leptin, pubmed-meshheading:11115775-Recombinant Proteins, pubmed-meshheading:11115775-Reverse Transcriptase Polymerase Chain Reaction
pubmed:year
2000
pubmed:articleTitle
Homologous and heterologous down-regulation of leptin receptor messenger ribonucleic acid in rat adrenal gland.
pubmed:affiliation
Department of Physiology, University of Córdoba, 14004 Córdoba, Spain. fi1tesem@uco.es
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't