Effect of ß3-adrenergic receptor on atrial L-type Ca(2+) current in rats with chronic heart failure.
Heart Lung Circ
; 23(4): 369-77, 2014 Apr.
Article
em En
| MEDLINE
| ID: mdl-24055266
ABSTRACT
OBJECTIVES:
To investigate the effect of selective ß3-adrenoreceptor agonist BRL-37344 on L-type Ca(2+) current (Ica,L) and mRNA expression of L-type Ca(2+) channel α2δ-2 (Cacna2d2) in rats with chronic heart failure (CHF).METHODS:
Twenty-four male Wistar rats were divided into normal control (n=6) and CHF group (n=18), which were further divided into CHF control and BRL group (0.4nmol/kg, IV, twice weekly for four weeks). Echocardiography was performed to assess the structure and function of the left atrium (LA).RESULTS:
The LA in the BRL group (4.4 ± 0.2mm) was larger than in the normal control (3.5 ± 0.3mm, P<0.01) or CHF control (4.0 ± 0.2mm, P<0.05) group. The LA ejection fraction in the BRL group (36.2 ± 4.2%) was lower than in the normal control (58.0 ± 3.1%, P<0.01) or CHF control group (42.3 ± 4.8%, P<0.05). There was no difference in Ica,L density between the BRL group and CHF control group (8.3 ± 1.7 vs. 8.2 ± 2.6 pA/pF, P>0.05), which was higher than in the normal control group (6.0 ± 1.8 pA/pF, P<0.01). There was no difference in the mRNA expression of α2δ-2 (Cacna2d2) between the BRL group and CHF control group (0.264 ± 0.005 vs. 0.243 ± 0.017, P>0.05), which was also higher than in the normal control group (0.137 ± 0.013, P<0.01).CONCLUSION:
ß3-Adrenoreceptor stimulation with BRL-37344 was associated with an increase in LA diameter and a decrease in LA function in chronic heart failure. These structural and function changes were not related to Ica,L or L-type Ca(2+) channel α2δ-2 (Cacna2d2) subunit in the LA myocytes.Palavras-chave
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Canais de Cálcio
/
Cálcio
/
Canais de Cálcio Tipo L
/
Receptores Adrenérgicos beta 3
/
Insuficiência Cardíaca
/
Miocárdio
Limite:
Animals
Idioma:
En
Ano de publicação:
2014
Tipo de documento:
Article