RESUMO
AIM: To investigate the effects of intracellular free calcium ([Ca 2+ ]i) from different resources on the proliferation mediated by mitogen activated protein kinase (MAPK) in vascular smooth muscle cells (VSMCs). METHODS: Cultured VSMCs were used in all experiments. Calcium influx was stimulated by angiotension Ⅱ(AngⅡ). The release of intracellular calcium stores was induced by inositol trisphosphate(IP 3) and ryanodine(RY). MAPK activity was measured by [?- 32 P]-ATP incorporation , MAPK protein expression by western blot, VSMCs proliferation by -Leucine(-Leu) and -Thymidine(-TdR) incorporation. RESULTS: Compared to the control VSMCs, AngⅡ, IP 3 and RY significantly increased [Ca 2+ ]i concentration , activity of MAPK and its protein content in VSMCs. The promotion of -Leu and -TdR incorporation in VSMCs was also observed ( P