Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
11
pubmed:dateCreated
2003-10-31
pubmed:abstractText
Ghrelin is a GH-releasing peptide that also has an important role as an orexigenic hormone-stimulating food intake. By measuring inositol phosphate turnover or by using a reporter assay for transcriptional activity controlled by cAMP-responsive elements, the ghrelin receptor showed strong, ligand-independent signaling in transfected COS-7 or human embryonic kidney 293 cells. Ghrelin and a number of the known nonpeptide GH secretagogues acted as agonists stimulating inositol phosphate turnover further. In contrast, the low potency ghrelin antagonist, [D-Arg1,D-Phe5,D-Trp7,9,Leu11]-substance P was surprisingly found to be a high potency (EC50 = 5.2 nm) full inverse agonist as it decreased the constitutive signaling of the ghrelin receptor down to that observed in untransfected cells. The homologous motilin receptor functioned as a negative control as it did not display any sign of constitutive activity; however, upon agonist stimulation the motilin receptor signaled as strongly as the unstimulated ghrelin receptor. It is concluded that the ghrelin receptor is highly constitutively active and that this activity could be of physiological importance in its role as a regulator of both GH secretion and appetite control. It is suggested that inverse agonists for the ghrelin receptor could be particularly interesting for the treatment of obesity.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Nov
pubmed:issn
0888-8809
pubmed:author
pubmed:issnType
Print
pubmed:volume
17
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
2201-10
pubmed:dateRevised
2007-11-15
pubmed:meshHeading
pubmed-meshheading:12907757-Amino Acid Sequence, pubmed-meshheading:12907757-Animals, pubmed-meshheading:12907757-Cell Line, pubmed-meshheading:12907757-Cercopithecus aethiops, pubmed-meshheading:12907757-Cyclic AMP Response Element-Binding Protein, pubmed-meshheading:12907757-Ghrelin, pubmed-meshheading:12907757-Humans, pubmed-meshheading:12907757-Inositol Phosphates, pubmed-meshheading:12907757-Ligands, pubmed-meshheading:12907757-Molecular Sequence Data, pubmed-meshheading:12907757-Molecular Structure, pubmed-meshheading:12907757-Obesity, pubmed-meshheading:12907757-Peptide Hormones, pubmed-meshheading:12907757-Receptors, G-Protein-Coupled, pubmed-meshheading:12907757-Receptors, Ghrelin, pubmed-meshheading:12907757-Response Elements, pubmed-meshheading:12907757-Signal Transduction, pubmed-meshheading:12907757-Type C Phospholipases
pubmed:year
2003
pubmed:articleTitle
High constitutive signaling of the ghrelin receptor--identification of a potent inverse agonist.
pubmed:affiliation
Laboratory for Molecular Pharmacology, Institute of Pharmacology, The Panum Institute, University of Copenhagen, DK-2200 Copenhagen, Denmark. b.holst@molpharm.dk.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't