调心方活性部位对β淀粉样蛋白抑制大鼠海马脑片CA1区诱发长时程增强的作用研究

Inhibitory Effect of Active Fraction of Tiaoxin Recipe on β-Amyloid Protein Induced Long-term Potentiation in CA1 Area of Rats' Hippocampal Slices

目的研究调心方活性部位A(activefractionofTiaoxinrecipe,TXR A)对β-淀粉样蛋白(betaarnyloidprotein ,βAP)抑制大鼠海马脑片长时程增强(long term potentiation ,LTP)效应的影响。方法采用细胞外微电极记录技术,记录大鼠海马脑片CA1区诱发群峰电位(populationspike,PS) ,然后施以10 0Hz,10 0串的强直刺激诱发LTP。结果与正常脑脊液组比较,β- AP(0. 2 μmol/L)孵育海马脑片>1 5h ,强直刺激后PS增幅程度显著降低,提示β- AP对海马LTP具有抑制作用;如用β- AP加TXR- A孵育脑片>1 5h ,则强直刺激后高浓度TXR -A组的PS平均幅度显著提高,且作用优于调心方,提示TXR- A可以增强LTP幅度。结论TXR A可能是发挥调心方改善β- AP抑制大鼠海马CA1区诱发LTP作用的主要成分之一,拮抗β- AP对LTP的抑制可能是其益智机制之一。

ObjectiveTo study the effect of the active fraction of Tiaoxin recipe (TXR-A), in inhibiting long-term potentiation (LTP) induced by beta amyloid protein (β-AP) in CA1 area of rats' hippocampal slices. MethodsThe population spike (PS) in CA1 area of hippocampal slices incubated in different medium was recorded before and after LTP was evoked by a 100Hz, 100 trains high frequency stimulation (HFS), using extracellular microelectrode recording techniques. ResultsThe amplitude of PS significantly decreased after HFS in hippocampal slices incubated in medium containing 0.2 μmol/L β-AP for more than 1.5 hour, as compared with that incubated in normal cerebrospinal fluid, the difference was significant, suggesting that β-AP could inhibit LTP in hippocampal slices. The average amplitude of PS in slices incubated in β-AP containing medium could be significantly enhanced by adding high-concentration TXR-A or TXR into the medium, and TXR-A showed a better effect of enhancing than that of TXR, indicating that TXR-A could increase the amplitude of LTP. ConclusionTXR-A may be the chief ingredient extracted from TXR for improving β-AP induced LTP in CA1 area of rats' hippocampus, to antagonise the inhibition of β-AP on LTP is possibly one of the mechanisms for its intelligence benefiting action.