cGMP-hydrolytic activity and its inhibition by sildenafil in normal and failing human and mouse myocardium.
J Pharmacol Exp Ther
; 330(3): 884-91, 2009 Sep.
Article
em En
| MEDLINE
| ID: mdl-19546307
ABSTRACT
In mouse models of cardiac disease, the type 5 (PDE5)-selective cyclic nucleotide phosphodiesterase inhibitor sildenafil has antihypertrophic and cardioprotective effects attributable to the inhibition of cGMP hydrolysis. To investigate the relevance of these findings to humans, we quantified cGMP-hydrolytic activity and its inhibition by sildenafil in cytosolic and microsomal preparations from the left ventricular myocardium of normal and failing human hearts. The vast majority of cGMP-hydrolytic activity was attributable to PDE1 and PDE3. Sildenafil had no measurable effect on cGMP hydrolysis at 10 nM, at which it is selective for PDE5, but it had a marked effect on cGMP and cAMP hydrolysis at 1 microM, at which it inhibits PDE1. In contrast, in preparations from the left ventricles of normal mice and mice with heart failure resulting from coronary artery ligation, the effects of sildenafil on cGMP hydrolysis were attributable to inhibition of both PDE5 and PDE1; PDE5 comprised approximately 22 and approximately 43% of the cytosolic cGMP-hydrolytic activity in preparations from normal and failing mouse hearts, respectively. These differences in PDE5 activities in human and mouse hearts call into question the extent to which the effects of sildenafil in mouse models are likely to be applicable in humans and raise the possibility of PDE1 as an alternative therapeutic target.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Inibidores de Fosfodiesterase
/
Piperazinas
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Sulfonas
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AMP Cíclico
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Insuficiência Cardíaca
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Miocárdio
Tipo de estudo:
Prognostic_studies
Limite:
Animals
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Humans
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Male
Idioma:
En
Ano de publicação:
2009
Tipo de documento:
Article