Linked Life Data

7955151

Source:http://linkedlifedata.com/resource/pubmed/id/7955151

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
6
pubmed:dateCreated
1994-12-16
pubmed:abstractText
The 2-amino-3-benzoylthiophene derivative PD 81,723 potentiates the A1 receptor-mediated negative dromotropic effect of exogenous adenosine and adenosine receptor agonists in guinea pig isolated perfused and in situ hearts. The objective of this study was to determine whether PD 81,723 could amplify the cardiac actions of endogenous adenosine. Two approaches known to increase the myocardial interstitial concentration of adenosine--hypoxia, which increases the production of adenosine and the inhibition of adenosine kinase, which decreases its metabolism--were used to test this hypothesis. In guinea pig hearts in situ, PD 81,723 (2 mg/kg i.v.) potentiated the atrioventricular (AV) nodal conduction delay caused by hypoxemia (PaO2, 14 to 19 mm Hg). In guinea pig isolated hearts, PD 81,723 (5 mumol/L) increased by twofold the stimulus-to-His bundle (S-H) interval prolongations induced by both a 5-minute period of hypoxia (25% O2/70% N2/5% CO2) and the administration of the adenosine kinase inhibitor iodotubercidin (40 to 70 nmol/L) but had no effect on coronary conductance. Hypoxia and hypoxia plus PD 81,723 (5 mumol/L) caused equivalent increases in the concentration of adenosine in epicardial transudate, from 0.13 +/- 0.15 to 0.48 +/- 0.1 and 0.45 +/- 0.4 mumol/L, respectively. Similar to the allosteric enhancer, the nucleoside uptake blocker draflazine (0.1 mumol/L) also increased by twofold the S-H interval prolongation caused by hypoxia. In contrast to the allosteric enhancer, draflazine increased the concentration of adenosine in epicardial transudate during hypoxia from 0.48 +/- 0.15 to 1.5 +/- 0.4 mumol/L. Draflazine also increased coronary conductance by approximately twofold in guinea pig normoxic constant-fold perfused hearts.(ABSTRACT TRUNCATED AT 250 WORDS)
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Dec
pubmed:issn
0009-7330
pubmed:author
pubmed:issnType
Print
pubmed:volume
75
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
972-80
pubmed:dateRevised
2007-11-15
pubmed:meshHeading
pubmed:year
1994
pubmed:articleTitle
Novel approach for enhancing atrioventricular nodal conduction delay mediated by endogenous adenosine.
pubmed:affiliation
Department of Medicine, University of Florida, Gainesville 32610.
pubmed:publicationType
Journal Article, Comparative Study, In Vitro, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't