Acceleration of contraction by β-adrenoceptor stimulation is greater in ventricular myocytes from failing than non-failing human hearts
Harding, S. E. ; Brown, L. A. ; Monte, F. ; Davies, C. H. ; O'Gara, P. ; Vescovo, G. ; Wynne, D. G. ; Poole-Wilson, P. A.
Springer
Published 1996
Springer
Published 1996
| ISSN: |
1435-1803
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|---|---|
| Keywords: |
Myocyte ; human ; relaxation ; β-adrenoceptors ; cyclic AMP
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| Source: |
Springer Online Journal Archives 1860-2000
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| Topics: |
Medicine
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| Notes: |
Abstract Myocytes from failing human ventricle contract and relax more slowly than those from non-failing. This has been suggested to result from the lowering of basal cyclic AMP level in failing myocardium, and the consequent withdrawal of a tonic lusitropic effect. We present data to support this hupothesis by demonstrating that the acceleration of contraction and relaxation by β-adrenoceptor stimulation is greater in myocytes from failing than nonfailing heart. This is despite the desensitisation of the inotropic effect of isorenaline in the same failing cells. Following β-adrenoceptor stimulation, speeds of contraction and relaxation are normalised in myocytes from failing heart, with final values not significantly different from non-failing.
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| Type of Medium: |
Electronic Resource
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| URL: |