Hypertrophied myocardium is more dependent on extracellular calcium than the normal cardiac muscle
Contribuinte(s) |
Universidade Estadual Paulista (UNESP) |
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Data(s) |
27/05/2014
27/05/2014
13/08/2010
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Resumo |
Background: The aim of this study was to analyze stable hypertrophied myocardial function and its response to inotropic maneuvers in rats submitted to renovascular hypertension for a 10-week period (RHT group, n=10). Material/Methods: Myocardial performance was studied in isolated left ventricle papillary muscles in isometric contraction under the following conditions: at postrest contraction of 30 seconds (PRC), at extracellular calcium (ECa 2+) chloride concentration of 1.25 and 5.20 mM, and after beta-adrenergic stimulation with 10 -6 M isoproterenol (ISOP). Results: The results were compared with normotensive Wistar controls rats (C group, n=10). In basal condition, resting tension, and contraction time (TPT) were greater, while relaxation time (RT 50) tended to be longer in RHT than C group. PRC and ISOP promoted a similar change in muscle function response intensity (Δ) in both groups. ECa 2+ shift did not change TPT in the C group and decreased TPT in the RHT animals; Δ was different between these groups. RT 50 increased in C and decreased in RHT, both without statistical significance; however, Δ was different. Conclusions: These results suggest that hypertrophied myocardial dysfunction may be attibuted to changes in intracellular calcium cycling. © Med Sci Monit, 2010. |
Identificador |
http://www.medscimonit.com/download/index/idArt/881100 http://www.ncbi.nlm.nih.gov/pubmed/20671609 Case Reports and Clinical Practice Review, v. 16, n. 8, 2010. 1507-6164 1643-3742 1234-1010 http://hdl.handle.net/11449/71818 WOS:000280762400010 2-s2.0-77955365642 WOS000280762400010.pdf |
Idioma(s) |
eng |
Relação |
Case Reports and Clinical Practice Review |
Direitos |
openAccess |
Palavras-Chave | #Calcium isoproterenol #Myocardium function #Papillary muscle #Renovascular hypertension #calcium ion #chloride #isoprenaline #animal experiment #animal model #animal tissue #beta adrenergic stimulation #calcium cell level #concentration (parameters) #controlled study #extracellular calcium #heart contraction #heart function #heart muscle fiber membrane steady potential #heart muscle relaxation #heart papillary muscle #heart performance #heart ventricle hypertrophy #inotropism #male #muscle isometric contraction #nonhuman #rat #renovascular hypertension #Wistar rat |
Tipo |
info:eu-repo/semantics/article |