Bone morphogenetic protein-4 contributes to the down-regulation of Kv4.3 K+ channels in pathological cardiac hypertrophy.
Biochem Biophys Res Commun
; 436(4): 591-4, 2013 Jul 12.
Article
em En
| MEDLINE
| ID: mdl-23747723
ABSTRACT
Kv4.3 K(+) channels contributing to Ito are involved in the repolarization of cardiac action potential. Kv4.3 K(+) channels decrease in pathological cardiac hypertrophy, but the mechanism remains unclear. Our previous study found that the expression of bone morphogenetic protein 4 (BMP4) increased in pressure-overload and Ang II constant infusion induced cardiac hypertrophy. Since the downregulation of Kv4.3 K(+) channels and the upregulation of BMP4 simultaneously occur in pathological cardiac hypertrophy, we hypothesize that the up-regulated BMP4 would contribute to the downregulation of Kv4.3 K(+) channels in cardiac hypertrophy. We found that BMP4 treatment reduced Kv4.3 but not Kv4.2 and Kv1.4 K(+) channel protein expression, and BMP4-induced decrease of Kv4.3 K(+) channel protein expression was reversed by BMP4 inhibitor noggin and DMH1 in cultured cardiomyocytes in vitro. BMP4-induced decrease of Kv4.3 K(+) channel protein expression was also reversed by the NADPH oxidase inhibitor apocynin and the radical scavenger tempol. In in vivo transverse aortic constriction (TAC)-induced cardiac hypertrophy, constant infusion of DMH1 completely rescued TAC-induced down-regulation of Kv4.3 K(+) channel protein expression. We conclude that BMP4 contributes to the downregulation of Kv4.3 K(+) channels in pathological cardiac hypertrophy and the underlying mechanism might be through increasing ROS production.
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Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Regulação para Baixo
/
Cardiomegalia
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Canais de Potássio Shal
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Proteína Morfogenética Óssea 4
Limite:
Animals
/
Humans
Idioma:
En
Revista:
Biochem Biophys Res Commun
Ano de publicação:
2013
Tipo de documento:
Article