Fu Min, Sun Zhao-hui, Zong Min, He Xiang-ping, Zuo Huan-cong, Xie Zuo-ping
Medical College of Tsinghua University, Beijing 100084, China.
Acta Pharmacol Sin. 2008 Aug;29(8):891-8. doi: 10.1111/j.1745-7254.2008.00821.x.
Deoxyschisandrin is one of the most effective composites of Schisandra chinensis, a famous Chinese medicine widely used as an antistress, anti-aging, and neurological performance-improving herb. In this study, we examined its specific mechanisms of action on cultured hippocampal neurons.
Hippocampal neurons, primarily cultured for 9-11 d in vitro, were used for this study. DS were dissolved in DMSO and applied to calcium imaging and whole-cell patch clamp.
The application of 3 mg/L DS decreased the frequency of spontaneous and synchronous oscillations of intracellular Ca2+ to 72%+/-2% (mean+/-SEM), and the spontaneous inhibitory postsynaptic currents to 60%+/-3% (mean+/-SEM). The inhibitory concentration 50% (IC50) for the effect of DS on calcium oscillations was 3.8 mg/L. DS also depressed the high voltage-gated Ca2+ channel and the voltage-gated Na+ channel currents at the same time point. It had no effect, however, on voltage-gated K+ and spontaneous excitatory postsynaptic currents.
DS inhibited the spontaneous and synchronous oscillations of intracellular Ca2+ through the depression of influx of extracellular calcium and the initiation of action potential. By repressing the spontaneous neurotransmitter release, DS modulated the neuronal network activities.
五味子醇甲是五味子最有效的成分之一，五味子是一种著名的中药，广泛用作抗应激、抗衰老和改善神经功能的草药。在本研究中，我们研究了其对培养的海马神经元的具体作用机制。
本研究使用体外原代培养9 - 11天的海马神经元。五味子醇甲溶解于二甲基亚砜中，并应用于钙成像和全细胞膜片钳实验。
应用3 mg/L五味子醇甲可使细胞内Ca2+的自发同步振荡频率降低至72%±2%（平均值±标准误），自发抑制性突触后电流降低至60%±3%（平均值±标准误）。五味子醇甲对钙振荡作用的半数抑制浓度（IC50）为3.8 mg/L。在同一时间点，五味子醇甲还同时抑制了高电压门控Ca2+通道和电压门控Na+通道电流。然而，它对电压门控K+通道和自发兴奋性突触后电流没有影响。
五味子醇甲通过抑制细胞外钙内流和动作电位的产生，抑制细胞内Ca2+的自发同步振荡。通过抑制自发神经递质释放，五味子醇甲调节神经元网络活动。
