Linked Life Data

2557149

Source:http://linkedlifedata.com/resource/pubmed/id/2557149

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
9
pubmed:dateCreated
1990-2-8
pubmed:abstractText
Dog saphenous vein spiral strips were employed to determine whether an intracellular source of Ca2+ is used for contraction upon activation of the alpha 2-adrenoceptor by B-HT 920 in Ca2+-free Krebs solution containing 50 microM EGTA. The studies were carried out in parallel with the activation of the alpha 1-adrenoceptor by phenylephrine (Phe) under the condition that B-HT 920 (10(-5) M) and Phe (2 x 10(-6) M) gave rise to a similar level of responses in Ca2+-containing Krebs solution. A similar level of responses to these agonists at equieffective concentrations in Ca2+-free medium were also observed. Such responses to Phe and B-HT 920 were inhibited by 10(-7) M rauwolscine and 10(-7) M prazosin, respectively, and were not affected by 10(-7) M nifedipine or 5 mM Mn2+. The responses to B-HT 920 (10(-5) M) and submaximal concentration of Phe (2 x 10(-6) M) in Ca2+-free medium were additive. However, if the vascular strips were first contracted maximally with 10(-4) M Phe in Ca2+-free medium to deplete the intracellular Ca store, subsequent addition of B-HT 920 failed to induce additional response. Our results strongly suggest that activation of alpha 2-adrenoceptor in dog saphenous vein in Ca2+-free medium indeed utilizes intracellular Ca2+ for contraction. We also found that the failure of earlier studies to demonstrate the contractile effects of B-HT 920 in dog saphenous vein was due to experimental artifacts derived from the use of high concentration of EGTA and artificial pH-buffering reagent.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
0008-4212
pubmed:author
pubmed:issnType
Print
pubmed:volume
67
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1086-91
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1989
pubmed:articleTitle
Does in vitro activation of postsynaptic alpha 2-adrenoceptor utilize intracellular Ca2+ for contraction in dog saphenous vein?
pubmed:affiliation
Department of Biomedical Sciences, Faculty of Health Sciences, McMaster University, Hamilton, Ont., Canada.
pubmed:publicationType
Journal Article, In Vitro, Research Support, Non-U.S. Gov't