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Predicate | Object |
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rdf:type | |
lifeskim:mentions | |
pubmed:issue |
2
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pubmed:dateCreated |
1986-6-27
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pubmed:abstractText |
Propranolol, timolol and sotalol were compared with respect to their cardiotoxic properties in isolated, spontaneously beating rat hearts. Propranolol and timolol induced a dose-dependent decrease in myocardial contractility. A high dose of sotalol had only modest negative inotropic effects. Similar reductions in myocardial contractility were observed in isolated, ventricle-stimulated rat hearts. These observations were similar to those in a previous study in which spontaneously beating and ventricle-stimulated reserpinized rat hearts were investigated. Spontaneously beating rat hearts were perfused with a high-, a normal- and a low-Ca++ medium, each with and without propranolol, timolol and sotalol. Addition of each beta-blocker to a normal-Ca++ medium induced a decrease of myocardial contractility and of heart rate and an increase of AV-conduction time when compared with the drug-free medium. In a high-Ca++ medium containing the same concentration of each beta-blocker, a less pronounced decrease of myocardial contractility was observed. Heart rate decreased and AV-conduction time increased to the same extent as after perfusion with the drug containing normal-Ca++ medium. With respect to the corresponding drug-free medium perfusion with a low-Ca++ medium with each beta-blocker enhanced the decline in myocardial contractility, most pronounced in propranolol and timolol containing media. For propranolol and sotalol the decrease in heart rate and increase in AV-conduction time were similar to the results after administration of the same beta-blocker in a high- and a normal-Ca++ perfusion media. Timolol caused an electromechanical dissociation. It was concluded that in beta-blocker intoxication the negative-inotropic phenomena cannot be explained by an action of the drugs on the beta-receptor since the results in reserpinized and non-reserpinized rat hearts were similar. Other effects have to be responsible for the observed cardiotoxic phenomena. The present results indicate that these phenomena can be influenced by Ca++ and or can be attributed to differences in lipophilicity.
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pubmed:language |
eng
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pubmed:journal | |
pubmed:citationSubset |
AIM
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pubmed:chemical |
http://linkedlifedata.com/resource/pubmed/chemical/Adrenergic beta-Antagonists,
http://linkedlifedata.com/resource/pubmed/chemical/Calcium,
http://linkedlifedata.com/resource/pubmed/chemical/Catecholamines,
http://linkedlifedata.com/resource/pubmed/chemical/Propranolol,
http://linkedlifedata.com/resource/pubmed/chemical/Sotalol,
http://linkedlifedata.com/resource/pubmed/chemical/Timolol
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pubmed:status |
MEDLINE
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pubmed:issn |
0731-3810
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pubmed:author | |
pubmed:issnType |
Print
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pubmed:volume |
24
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pubmed:owner |
NLM
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pubmed:authorsComplete |
Y
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pubmed:pagination |
111-33
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pubmed:dateRevised |
2006-11-15
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pubmed:meshHeading |
pubmed-meshheading:2872335-Adrenergic beta-Antagonists,
pubmed-meshheading:2872335-Animals,
pubmed-meshheading:2872335-Calcium,
pubmed-meshheading:2872335-Catecholamines,
pubmed-meshheading:2872335-Coronary Circulation,
pubmed-meshheading:2872335-Electric Stimulation,
pubmed-meshheading:2872335-Heart,
pubmed-meshheading:2872335-Heart Conduction System,
pubmed-meshheading:2872335-Heart Rate,
pubmed-meshheading:2872335-Male,
pubmed-meshheading:2872335-Myocardial Contraction,
pubmed-meshheading:2872335-Propranolol,
pubmed-meshheading:2872335-Rats,
pubmed-meshheading:2872335-Rats, Inbred Strains,
pubmed-meshheading:2872335-Sotalol,
pubmed-meshheading:2872335-Timolol
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pubmed:year |
1986
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pubmed:articleTitle |
Calcium interferes with the cardiodepressive effects of beta-blocker overdose in isolated rat hearts.
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pubmed:publicationType |
Journal Article,
In Vitro
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