Long-term effects of selective and nonselective endothelin receptor antagonists in mice with heart failure

Maria A Cavasin, Oscar A Carretero, Fang Yang, Nancy Oja-Tebbe, Hongmei Peng, Xiao-Ping Yang
Journal of Cardiac Failure 2002, 8 (4): 254-61

BACKGROUND: The ET(A) and ET(B) receptors mediate vasoconstriction, aldosterone release, and fibrosis. However, the role of ET(B) receptors is still controversial because those expressed on endothelial cells also stimulate vasodilatation and may oppose the actions of the ET(A) receptor. Plasma levels of endothelin-1 (ET-1) are increased in heart failure (HF) and are associated with myocardial dysfunction. The relative efficacy of selective and nonselective ET antagonists in the treatment of HF is unclear. We hypothesized that blockade of ET(A) receptors may improve cardiac function and prevent left ventricular remodeling in mice with HF, and these effects may be mediated in part by activation of ET(B).

METHODS AND RESULTS: A mouse model of chronic HF induced by myocardial infarction (MI) was used. Seven days after MI, mice were divided into vehicle, ET(A)-ant, or ET(A/B)-ant groups and treated for 23 weeks. Cardiac function, LV dimensions, and hemodynamics were evaluated in conscious mice before MI and during treatment. Histologic analysis of the heart and liver was performed at the end of the study. HF significantly decreased EF and increased LV dimensions, interstitial collagen fraction (ICF) and myocyte cross-sectional area (MCSA). Both ET(A)-ant and ET(A/B)-ant slightly increased EF but had no significant effect on LV dimensions, hypertrophy, or ICF. Both treatments decreased MCSA; however, this was only significant in the ET(A/B)-ant group.

CONCLUSIONS: Both selective and nonselective ET-ant have similar slight effects on cardiac function and remodeling. This suggests that (1) ET(B) receptors do not mediate the beneficial cardiac effects of ET(A)-ant and (2) blockade of the ET system alone may not provide significant cardioprotection, at least in mice with HF induced by MI.

Full Text Links

Find Full Text Links for this Article


You are not logged in. Sign Up or Log In to join the discussion.

Trending Papers

Remove bar
Read by QxMD icon Read

Save your favorite articles in one place with a free QxMD account.


Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"