Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
1993-8-5
pubmed:abstractText
Subthreshold concentrations of endothelin-1 potentiated the norepinephrine-induced contraction in isometrically mounted rings of the rabbit aorta. Pretreatment with endothelin-1 (0.1 nM) for 10 minutes increased the sensitivity of the aortic rings to norepinephrine without affecting the maximal contraction. This amplification was unaffected by removal of the endothelium but was prevented by the protein kinase C inhibitors staurosporine (0.01 microM) and calphostin C (0.1 microM). Pretreatment of the aortic rings for 24 hours with phorbol 12-myristate 13-acetate (0.1 microM) also abolished the potentiation. Norepinephrine-induced contraction was potentiated by pretreating with phorbol 12-myristate 13-acetate (10 nM) and by increasing the concentration of K+ in the bath solution from 4.6 to 8.6 mM. The potentiation of the norepinephrine-induced contraction by endothelin-1 (0.1 nM) or by phorbol 12-myristate 13-acetate (10 nM) was not associated with an increase in norepinephrine-induced 45Ca2+ uptake or influx, whereas the potentiation due to an increase in the concentration of K+ in the bath solution from 4.6 to 8.6 mM was associated with an increase in norepinephrine-induced 45Ca2+ uptake. We conclude that endothelin-1 potentiation of the norepinephrine-induced contraction occurs in the absence of changes in stimulated Ca2+ entry and is endothelium independent. It is probable that endothelin-1 increases the sensitivity of the contractile apparatus to Ca2+ by activating protein kinase C-dependent mechanisms.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jul
pubmed:issn
0194-911X
pubmed:author
pubmed:issnType
Print
pubmed:volume
22
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
78-83
pubmed:dateRevised
2007-11-15
pubmed:meshHeading
pubmed:year
1993
pubmed:articleTitle
Potentiation of norepinephrine-induced contractions by endothelin-1 in the rabbit aorta.
pubmed:affiliation
Department of Pharmacology, University of Vermont, College of Medicine, Burlington 05405-0068.
pubmed:publicationType
Journal Article, In Vitro, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't