Mitogen activated protein kinase in calcium activator mediated cardiomyocyte hypertrophy
Yong Yang · Chinese Heart Journal · 2002
AIM:To investigate the effect of intracellular free calcium ([Ca 2+ ] i) from different sources on the hypertrophy of cardiomyocytes mediated by mitogen activated protein kinase (MAPK). METHDOS:Calcium influx was stimulated with angiotension Ⅱ(AngⅡ),calcium was released with inositol (1,4,5) trisphosphate (IP 3) in cultured rat cardiomyocytes, MAPK activity and MAPK protein expression were measured by γ 32 P ATP incorporation and by western blot respectively;cardiomyocytes hypertrophy was marked by 3H Leucine( 3H Leu) and 3H Thymidine( 3H TdR) incorporations. RESULTS:AngⅡ and IP 3 could increase MAPK activity and MAPK protein content,and promote 3H Leu and 3H TdR incorporations in cardiomyocytes,which were significantly different from those of the controlled cardiomyocytes( P 0.01). CONCLUSION:cardiomyocyte proliferation closely related with the [Ca 2+ ] i concentration.