In:
American Journal of Physiology-Heart and Circulatory Physiology, American Physiological Society, Vol. 304, No. 9 ( 2013-05-01), p. H1267-H1276
Abstract:
The importance of chronic stimulation of β-adrenoceptors in the development of cardiac dysfunction is the rationale for the use of β-blockers in the treatment of heart failure. Nebivolol is a third-generation β-blocker, which has further properties including stimulation of endothelial nitric oxide synthase and/or β 3 -adrenoceptors. The aim of this study was to investigate whether nebivolol has additional effects on β-adrenoceptor-mediated functional responses along with morphologic and molecular determinants of cardiac hypertrophy compared with those of metoprolol, a selective β 1 -adrenoceptor blocker. Rats infused by isoprenaline (100 μg·kg −1 ·day −1 , 14 days) were randomized into three groups according to the treatment with metoprolol (30 mg·kg −1 ·day −1 ), nebivolol (10 mg·kg −1 ·day −1 ), or placebo for 13 days starting on day 1 after implantation of minipump. Both metoprolol and nebivolol caused a similar reduction on heart rate. Nebivolol mediated a significant improvement on cardiac mass, coronary flow, mRNA expression levels of sarcoplasmic reticulum Ca 2+ ATPase (SERCA2a) and atrial natriuretic peptide and phospholamban (PLN)/SERCA2a and phospho-PLN/PLN ratio compared with metoprolol and placebo. Nebivolol prevented the detrimental effects of isoprenaline infusion on isoprenaline (68% of control at 30 μM), BRL37344 (63% of control at 0.1 μM), and forskolin (64% of control at 1 μM) responses compared with metoprolol (isoprenaline, 34% of control; BRL37344, no response; forskolin, 26% of control) and placebo (isoprenaline, 33% of control; BRL37344, 28% of control; forskolin, 12% of control). Both β-blockers improved the changes in mRNA expressions of β 1 - and β 3 -adrenoceptors. Our results suggest that nebivolol partially protects the responsiveness of β-adrenoceptor signaling and the development of cardiac hypertrophy independent of its β 1 -adrenoceptor blocking effect.
Type of Medium:
Online Resource
ISSN:
0363-6135
,
1522-1539
DOI:
10.1152/ajpheart.00352.2012
Language:
English
Publisher:
American Physiological Society
Publication Date:
2013
detail.hit.zdb_id:
1477308-9
SSG:
12
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