[Role and regulation of calcineurin-dependent signal pathway in cardiac hypertrophy of rats].

The present study investigated the role and regulation of calcineurin-dependent signal pathway in cardiac hypertrophy of rats from the three levels of animal model, culturing cells and molecular biology. The results showed as follows: (1) Calcineurin signal pathway involves in myocyte hypertrophy induced by various factors such as hemodynamic overload, myocardial fibrosis, paracrine/autocrine factors, etc.; (2) Calcineurin-dependent signal pathway plays an important role not only in AngII- and bFGF-induced cardiac myocyte hypertrophy but also in AngII- and bFGF-stimulated cardiac fibroblast proliferation. (3) Calcineurin pathway may associate with MAPK and PKC pathways at several levels; (4) Activation of calcineurin depends on sustained increase of intracellular calcium concentration and is regulated by protein phosphorylation. The expression of calcineurin gene in AngII-stimulated myocytes might be regulated by Ca2+ signal and MAPK cascade. In conclusion, Ca(2+)-calcineurin signal pathway involves in the development of cardiac hypertrophy of rats.