Linked Life Data

1699437

Source:http://linkedlifedata.com/resource/pubmed/id/1699437

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
4 Pt 2
pubmed:dateCreated
1990-11-19
pubmed:abstractText
We examined the effects of leukotrienes (LT) B4, C4, D4, and E4 (0.010-2.5 ng/ml) on contractile and coronary function in isolated rat hearts. Concentration-dependent effects were examined either by the cumulative addition of LTs or by addition of specific concentrations to individual preparations. Neither LTB4 nor LTE4 produced myocardial or coronary effects at any concentration, irrespective of addition protocol. At 0.010 ng/ml, both LTC4 and LTD4 produced an increase in force that was associated with a 30% elevation in coronary pressure. Further cumulative addition of either leukotriene resulted in a negative inotropic effect and a further increase in coronary pressure. In contrast, following single additions of LTC4 or LTD4 (0.01-0.50 ng/ml) a positive inotropic effect and an increased coronary pressure were observed. LTC4 or LTD4 at 0.5 ng/ml produced a negative inotropic effect in hearts pretreated with 0.01 ng/ml of LTD4 or LTC4, respectively. Reversal of this addition protocol resulted in a negative inotropic effect of either 0.01 ng/ml LTD4 or LTC4. Verapamil and nifedipine significantly attenuated the positive inotropic and coronary constricting effect of 0.5 ng/ml LTC4 and LTD4. The addition of either LT following BAY K 8644 resulted in a negative inotropic effect, in contrast to the positive inotropic influence seen with leukotriene alone. Our results demonstrate a positive inotropic effect of low concentrations of LTC4 and LTD4 concomitant with coronary artery constriction, a phenomenon determined by leukotriene addition protocols and suggestive of LTC4/LTD4 receptor interaction. The effects of calcium channel antagonists and BAY K 8644 on the inotropic response suggest a leukotriene-mediated activation of the calcium channel resulting in increased intracellular calcium concentrations.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
0002-9513
pubmed:author
pubmed:issnType
Print
pubmed:volume
259
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
H1239-46
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1990
pubmed:articleTitle
Positive inotropic effects of low concentrations of leukotrienes C4 and D4 in rat heart.
pubmed:affiliation
Department of Pharmacology and Toxicology, University of Western Ontario, London, Canada.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't