神经肽Y经Ca(上标 2+)/CaM依赖的钙调神经磷酸酶途径诱导心肌细胞肥大

Objective To investigate the role of Ca Ca(superscript 2+)/calmodulin-dependent calcineurin (CaN) signaling pathway in neuropeptide Y (NPY)-induced cardiomyocyte hypertrophy in rat. Methods Cardiomyocytes of neonatal Wistar rats were cultured in the presence of 10 and 100 nmol/L NPY, and cyclosporine A (CsA) was applied to inhibit the activity of CaN. The protein synthesis rate, c-jun mRNA expression, CaN protein expression, CaN activity and intracellular Ca(superscript 2+) concentration in the cardiomyocytes were assessed. Results Compared with the control group, 3H-Leu incorporation and expression of c-jun mRNA in the cardiomyocytes treated with 100 nmol/L NPY increased significantly (P＜0.05, P＜0.001), and the effect of NPY was blocked by CsA. The activity of CaN (P＜0.05), CaN expression (P＜0.05), and Ca(superscript 2+) concentration in the cytoplasm (P＜0. 001) and nuclei (P＜0.001) of the cells with 100 nmol/L NPY treatment also significantly increased compared with those in the control cells. Conclusion NPY can induce cardiomyocyte hypertrophy in rats, in which process Ca(superscript 2+)/calmodulin-dependent CaN signaling pathway plays an important role.