Astragaloside Ⅳ inhibits spontaneous synaptic transmission and synchronized Ca2+ oscillations on hippocampal neurons

• 来源期刊: 中国药理学报（英文版）
• 关键词: astragaloside Ⅳ synchronized spontaneous Ca2+ oscillation spontaneous synaptic transmission voltage-gated Na+ currents voltage-gated K+ currents
• 年，卷（期）: 2008,（1）
• 页码范围: 57-64
• 页数: 8页
• 语种: 英文
• DOI: 10.1111/j.1745-7254.2008.00712.x

摘要

Aim: To investigate the changes in the spontaneous neuronal excitability in-duced by astragaloside Ⅳ (AGS-Ⅳ) in the cultured hippocampal network. Methods: Hippocampal neurons in culture for 9-11 d were used for this study. The sponta-neous synaptic activities of these hippocampal neurons were examined by Ca2+ imaging and whole-cell patch-clamp techniques. In total, 40 mg/L AGS-Ⅳ dis-solved in DMSO and 2 mL/L DMSO were applied to the neurons under a micro-scope while the experiments were taking place. Results: AGS-Ⅳ inhibited the frequencies of synchronized spontaneous Ca2+ oscillations to 59.39%+3.25% (mean+SEM), the spontaneous postsynaptic currents to 43.78%±7.72% (mean±SEM), and the spontaneous excitatory postsynaptic currents to 49.25%±7.06% (mean±SEM) of those of the control periods, respectively, at 16 min after the AGS-Ⅳ applications. AGS-Ⅳ also decreased the peak values of the voltage-gated K+ and Na+ channel currents at that time point. Conclusion: These results indicate that AGS-Ⅳ suppresses the spontaneous neuronal excitabilities effectively. Such a modulation of neuronal activity could represent new evidence for AGS-Ⅳ as a neuroprotector.