Effects of combined inhibition of the Na+-H+ exchanger and angiotensin-converting enzyme in rats with congestive heart failure after myocardial infarction.
Br J Pharmacol
; 146(5): 723-31, 2005 Nov.
Article
em En
| MEDLINE
| ID: mdl-16151439
ABSTRACT
1 We investigated the single vs the combined long-term inhibition of Na(+)-H(+) exchanger-1 (NHE-1) and ACE in rats with congestive heart failure induced by myocardial infarction (MI). 2 Rats with MI were randomized to receive either placebo, cariporide (3000 p.p.m. via chow), ramipril (1 mg kg(-1) day(-1) via drinking water) or their combination for 18 weeks starting on day 3 after surgery. 3 Cardiac morphology and function was assessed by echocardiography and by means of a 2.0 F conductance catheter to determine left ventricular (LV) pressure volume relationships. 4 MI for 18 weeks resulted in an increase in LV end-diastolic diameter (LVDed) in the placebo-treated group when compared to sham (placebo 1.1+/-0.04 cm; sham 0.86+/-0.01; P<0.05). Combined inhibition of NHE-1 and ACE, but not the monotherapies, significantly reduced LVDed (1.02+/-0.02 cm). 5 Preload recruitable stroke work (PRSW), dp/dt(max) (parameter of systolic function) and end-diastolic pressure volume relationship (EDPVR, diastolic function) were significantly impaired in placebo-treated MI group (PRSW 39+/-7 mmHg; dp/dt(max) 5185+/-363 mmHg s(-1); EDPVR 0.042+/-0.001 mmHg microl(-1); all P<0.05). Cariporide treatment significantly improved PRSW (64+/-7 mmHg), dp/dt(max) (8077+/-525 mmHg s(-1)) and EDPVR (0.026+/-0.014 mmHg microl(-1)), and reduced cardiac hypertrophy in rats with MI. Combined inhibition of NHE-1 and ACE had even a more pronounced effect on PRSW (72+/-5 mmHg) and EDPVR (0.026+/-0.014 mmHg microl(-1)), as well as cardiac hypertrophy that, however, did not reach statistical significance compared to cariporide treatment alone. 6 The NHE-1 inhibitor cariporide significantly improved LV remodeling and function in rats with congestive heart failure induced by MI. The effect of cariporide was comparable or tended to be stronger (e.g. systolic function) compared to ramipril. Combined treatment with cariporide and ramipril tended to be more effective on LV remodeling in rats with heart failure than the single treatments. Thus, inhibition of the NHE-1 may be a promising novel therapeutic approach for the treatment of congestive heart failure.
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Inibidores da Enzima Conversora de Angiotensina
/
Ramipril
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Trocadores de Sódio-Hidrogênio
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Peptidil Dipeptidase A
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Insuficiência Cardíaca
/
Infarto do Miocárdio
Limite:
Animals
Idioma:
En
Ano de publicação:
2005
Tipo de documento:
Article