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Predicate | Object |
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rdf:type | |
lifeskim:mentions | |
pubmed:issue |
2
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pubmed:dateCreated |
1985-8-13
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pubmed:abstractText |
Effects of calcium antagonists and Ni2+ on the positive inotropic responses to histamine mediated by H1-receptors were investigated in left atria of guinea pigs. The preparations were electrically driven at 0.5 Hz in Krebs-Henseleit solution at a temperature of 30 degrees C unless stated otherwise. Histamine in low concentrations of 10 and 100 nmol/1 produced a monophasic positive inotropic effect, whereas in concentrations higher than 1 mumol/1 it exerted a multiphasic inotropic response composed of an initial increasing phase (initial component) and a second and late developing, greater positive inotropic phase (second component). These two components were sometimes separated by a transient decrease in developed tension. Both positive inotropic components caused by 3 mumol/1 histamine were inhibited by the H1-antagonists mepyramine, D-chlorpheniramine and diphenhydramine in a concentration-dependent manner, but not by the H2-antagonist cimetidine. Pretreatment with Ni2+ in concentrations of 0.2 and 0.5 mmol/1 preferentially suppressed the second component of the inotropic effect produced by 3 mumol/1 histamine without significantly affecting the initial component. On the other hand, the monophasic positive inotropic effect of 30 nmol/1 histamine was almost unaffected by this cation. The concentration-response curves for the positive inotropic effect of histamine were hardly influenced by Ni2+ in the range of lower concentrations of histamine, but significantly suppressed in the range of higher concentrations of the agonist.(ABSTRACT TRUNCATED AT 250 WORDS)
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pubmed:language |
eng
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pubmed:journal | |
pubmed:citationSubset |
IM
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pubmed:chemical |
http://linkedlifedata.com/resource/pubmed/chemical/Calcium Channel Blockers,
http://linkedlifedata.com/resource/pubmed/chemical/Catecholamines,
http://linkedlifedata.com/resource/pubmed/chemical/Histamine,
http://linkedlifedata.com/resource/pubmed/chemical/Histamine Antagonists,
http://linkedlifedata.com/resource/pubmed/chemical/Nickel,
http://linkedlifedata.com/resource/pubmed/chemical/Receptors, Histamine,
http://linkedlifedata.com/resource/pubmed/chemical/Receptors, Histamine H1,
http://linkedlifedata.com/resource/pubmed/chemical/Reserpine
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pubmed:status |
MEDLINE
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pubmed:month |
Apr
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pubmed:issn |
0028-1298
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pubmed:author | |
pubmed:issnType |
Print
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pubmed:volume |
329
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pubmed:owner |
NLM
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pubmed:authorsComplete |
Y
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pubmed:pagination |
188-94
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pubmed:dateRevised |
2006-11-15
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pubmed:meshHeading |
pubmed-meshheading:4010796-Animals,
pubmed-meshheading:4010796-Calcium Channel Blockers,
pubmed-meshheading:4010796-Catecholamines,
pubmed-meshheading:4010796-Electric Stimulation,
pubmed-meshheading:4010796-Female,
pubmed-meshheading:4010796-Guinea Pigs,
pubmed-meshheading:4010796-Heart,
pubmed-meshheading:4010796-Heart Atria,
pubmed-meshheading:4010796-Histamine,
pubmed-meshheading:4010796-Histamine Antagonists,
pubmed-meshheading:4010796-Male,
pubmed-meshheading:4010796-Myocardial Contraction,
pubmed-meshheading:4010796-Nickel,
pubmed-meshheading:4010796-Receptors, Histamine,
pubmed-meshheading:4010796-Receptors, Histamine H1,
pubmed-meshheading:4010796-Reserpine,
pubmed-meshheading:4010796-Time Factors
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pubmed:year |
1985
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pubmed:articleTitle |
Effect of Ni2+ on the multiphasic positive inotropic responses to histamine mediated by H1-receptors in left atria of guinea pigs.
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pubmed:publicationType |
Journal Article,
In Vitro
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