Linked Life Data

19680632

Source:http://linkedlifedata.com/resource/pubmed/id/19680632

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
5
pubmed:dateCreated
2009-10-21
pubmed:abstractText
Human urotensin-II (U-II) is an 11-amino-acid cyclic peptide that activates a G(q)-coupled receptor named UT. Little is known about the desensitisation profile of this receptor as peptide binding is essentially irreversible. In the present study, we have examined the effects of U-II and carbachol on Ca(2+) signalling in SJCRH30 rhabdomyosarcoma (receptor density, B(max) approximately 0.1 pmol/mg protein) and human embroynic kidney (HEK)(hUT) (B(max) approximately 1.4 pmol/mg protein) cells expressing native and recombinant UT, respectively. In SJCRH30, HEK(hUT) and human peripheral blood mononuclear cells induced to express native UT by treatment with 2 microg/ml lipopolysaccharide (LPS), we have measured the effects of U-II treatment on UT mRNA. In SJCRH30 cells, primary stimulation with carbachol (250 microM) did not affect a secondary challenge with U-II (1 microM) and primary challenge with U-II did not affect a secondary challenge with carbachol. In contrast, in HEK(hUT) cells, primary stimulation with carbachol (250 microM) reduced a secondary challenge to U-II (1 microM) by 84% and primary challenge with U-II reduced a secondary challenge to carbachol by 76%. Pre-treatment of SJCRH30 cells with U-II reduced UT mRNA after 6 h and this returned to basal after 24 h. In recombinant HEK(hUT) cells, UT mRNA expression increased following a 6 h treatment with 1 microM U-II. U-II treatment of naïve un-stimulated peripheral blood mononuclear cells was without effect. However, when UT expression is up-regulated following 15 h of LPS treatment, a 6 h U-II challenge reduced UT mRNA by 66%. In summary, we report differences in the desensitisation profiles of native and recombinant U-II receptors. Design and interpretation of functional experiments are hampered by irreversibility of U-II binding.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Nov
pubmed:issn
1432-1912
pubmed:author
pubmed:issnType
Electronic
pubmed:volume
380
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
451-7
pubmed:meshHeading
pubmed:year
2009
pubmed:articleTitle
Desensitisation of native and recombinant human urotensin-II receptors.
pubmed:affiliation
Division of Anaesthesia, Critical Care and Pain Management, University Department of Cardiovascular Sciences (Pharmacology and Therapeutics Group), University of Leicester, Leicester, LE1 5WW, UK.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't