,Ginsenoside Rg1 activated CaMKIIα mediated extracellular signal-regulat-ed kinase/mitogen activated

• 作 者: Jin-feng HU Wei XUE Na NING Yu-he YUAN Jun-tian ZHANG Nai-hong CHEN
• 机 构: Department of Pharmacology, Institute of Materia Medica, Chinese Academy of Medical Sciences & Pekin
• 出 处: 中国药理学报（英文版）
• 发表日期: 2008年9期
• 关键词: ginsenoside Rg1 ERK1/2 CaMKIIα CREB

Aim:We carried out this study to investigate the effect of ginsenoside Rg1 on the extracellular signal-regulated kinase/mitogen activated protein kinase (ERK/ MAPK) pathway for understanding its effect on synaptic platicity. Methods: Weste blotting and immunostaining were used to examine the phosphorylation of ERK1/2, CaMKIIα and cAMP response element binding protein (CREB) in PC12 cells and synaptosomes. The confocal microscopy and fluorescent indica-tor Fluo-3 was applied to observe the intracellular calcium ion flux. Results: The phosphorylation of ERK1/2 in PC12 cells and synaptosomes incubated with Rg1 was increased and reached maximum at 4 min. Rg1 also promoted the transient enhancement of upstream calcium ion and activated CaMKIIα, which reached maximum at 2 min. CREB, the downstream protein, was phosphorylat-ed within 8 min in PC12 cells after being incubated with Rg1. Moreover, KN93 partially inhibited the activation of ERK1/2, and PD98059 also partially blocked the phosphorylation of CREB. Conclusions: Rg1 activated ERK/MAPK path-way by CaMKIIα, and the activation of CREB was not only dependent on ERK induced by Rg1, which may provide an explanation for the effect of Rg1 on long-term potentiation.