Efeito do treinamento físico em modelo genético de insuficiência cardíaca induzida por hiperatividade simpática / The Therapeutic effect of exercise training in genetic model of heart failure induced by sympathetic hyperactivity

AUTOR(ES)
DATA DE PUBLICAÇÃO

2007

RESUMO

The sympathetic nervous activity is increased in heart failure (HF) and is associated with the severity and prognosis of disease. Mice lacking both α2A and α2C adrenergic receptors (α2A/α2CARKO) develop sympathetic hyperactivity- induced HF and present 50% mortality rate by seven mo of age. The decreased cardiac contractility, cardiomyocytes degradation and exercise intolerance suggest that these mice are a good genetic model to unravel molecular mechanisms involved in the improvements of ventricular function by different pharmacological and non-pharmacological therapies for HF. The present study was underlined to test the possible therapeutic effect of exercise training in sympathetic hyperactivity- induced HF. The improved exercise tolerance and systolic function after exercise training in α2A/α2CARKO was accompanied by increased intracellular Ca2+ transient and the expression of cardiac proteins which regulate Ca2+ transients, such as expression SERCA2 (20%), phospho-PLB-Ser16 (92%), phospho-PLB-Tre17 (285%), paralleled by reduction in NCX and PP1 expression. Therefore, this study provide direct evidence for the altered intracellular Ca2+ signaling in α2A/α2CARKO mice and that exercise training improves the ventricular function associated with an increase in intracellular Ca2+ transient in cardiomyocyte.

ASSUNTO(S)

transporte intracelular de ca2+ exercise training insuficiência cardíaca treinamento físico ca2+ signaling heart failure

Documentos Relacionados