Membrane localization, Caveolin-3 association and rapid actions of vitamin D receptor in cardiac myocytes.
Steroids
; 75(8-9): 555-9, 2010.
Article
em En
| MEDLINE
| ID: mdl-20015453
ABSTRACT
The active form of vitamin D, 1alpha, 25-dihydroxyvitamin D(3) (1,25(OH)(2)D(3)), mediates both genomic and rapid non-genomic actions in heart cells. We have previously shown that the vitamin D receptor (VDR) is located in the t-tubular structure of cardiomyocytes. Here we show that VDR specifically interacts with Caveolin-3 in the t-tubules and sarcolemma of adult rat cardiac myocytes. Co-immunoprecipitation studies using VDR antibodies revealed that Caveolin-3 specifically co-precipitates with the VDR and similarly the VDR is co-precipitated with Caveolin-3 antibody. Confocal immuno-fluorescence microscopy analysis also showed co-localization of VDR and Caveolin-3 in t-tubules and sarcolemma. The non-genomic effects of the functional VDR were studied in electrically stimulated myocytes isolated from adult rat hearts. Sarcomere shortening and re-lengthening were measured in 1,25(OH)(2)D(3) treated cardiac myocytes. A 1nM treatment decreased peak shortening within minutes, suggesting a rapid effect through the membrane-bound VDR. This novel finding of the interaction between VDR and Caveolin-3 is fundamentally important in understanding 1,25(OH)(2)D(3) signal transduction in heart cells and provides further evidence that VDR plays a role in regulation of heart structure and function.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Membrana Celular
/
Receptores de Calcitriol
/
Miócitos Cardíacos
/
Caveolina 3
Tipo de estudo:
Risk_factors_studies
Limite:
Animals
Idioma:
En
Ano de publicação:
2010
Tipo de documento:
Article