Linked Life Data

1300036

Source:http://linkedlifedata.com/resource/pubmed/id/1300036

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
5
pubmed:dateCreated
1993-5-18
pubmed:abstractText
The effects of tetrandrine (Tet) on the contractile properties of rat aortic ring preparations were studied to test the hypothesis that Tet is a Ca2+ antagonist acting on voltage-operated Ca2+ channels (VOC). The tests were performed on contractions induced by depolarizing concentrations of KCl and by alpha 1-adrenoceptor agonist, phenylephrine (Phe). These vascular effects of Tet were compared to those of nifedipine (Nif). We found that Tet behaved qualitatively similar to, but less potent than, Nif in that it inhibited KCl-induced contraction in a concentration-dependent fashion and its inhibitory effect was long-lasting. However, the effects on Phe-induced contraction of Tet was different from those of Nif in that the extracellular Ca(2+)-dependent contraction was inhibited by Tet, but not by Nif. Tet (60 mumol.L-1) completely inhibited the 45Ca2+ uptake induced by KCl and Phe in rat aortic muscle strips. When the aortic muscle contractile response was induced by addition of Ca2+ following depletion of intracellular stores by Phe in the presence of sarcoplasmic reticulum Ca(2+)-pump inhibitor, cyclopiazonic acid, Tet (60 mumol.L-1) was more effective than Nif 1 mumol.L-1 in inhibiting such a response to extracellularly added Ca2+. Furthermore, Tet, but not Nif, also significantly inhibited the contraction to Phe in Ca(2+)-free medium. Collectively, these results led us to conclude that Tet does not behave as a selective VOC blocker like Nif.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
0253-9756
pubmed:author
pubmed:issnType
Print
pubmed:volume
13
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
385-90
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1992
pubmed:articleTitle
Tetrandrine is not a selective calcium channel blocker in vascular smooth muscle.
pubmed:affiliation
Department of Biomedical Sciences, McMaster University, Hamilton, Ontario, Canada.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't