枸杞多糖对动物海马电活动的影响

Effects of Lycium Barbarum Polysaccharide on Hippocampal Activity in Animals

目的 :观察枸杞多糖 (LBP)与由情绪和本能所控制的复杂行为的生理活动有关的海马电生理的影响。方法 :采用慢性埋藏电极记录清醒兔海马脑电波 (EEG)和急性埋藏电极记录麻醉大鼠海马齿状回基础诱发电位及高频条件刺激引发海马齿状回长时程增强现象 (LTP)的实验方法 ,并采用频谱分析法判断给药前后脑电波幅变化 ,判断LBP对海马自发脑电活动的影响 ;以及采用诱发电位的群峰电位幅度 (PSamplitude)和兴奋性突触后电位始段上升斜率 (pEPSPslope)两项指标 ,研究药物对基础诱发电位及弱条件刺激 (6 0Hz ,30pulses)和强条件刺激 (10串间隔为 2 0 0ms的高频刺激 ,每串刺激由波宽 80 μs、频率 40 0Hz的 5个刺激方波组成 )引发的LTP的影响。结果 :(1)腹腔注射 30、6 0mg·kg-1剂量的LBP ,对清醒兔海马脑电波有增幅作用 ,而 12 0mg·kg-1剂量对海马脑电波幅没有影响。 (2 )对麻醉大鼠海马齿状回基础诱发电位及高频刺激引发海马齿状回长时程增强现象没有影响。结论 :LBP对海马自发电活动有促进作用 ,提示LBP有潜在的促智作用。

Objective: To investigate the effects of Lycium barbarum polysaccharide(LBP) on electrophysiological activity in hippocampus which is involved in the complex physical aspects of behaviour governed by emotion and instinct. Methods:Hippocampal electroencephalogram(EEG) and evoked potentials were employed to evaluate θ activity, the slope of population excitatory postsynaptic potential (pEPSP) slope and the amplitude of population spike (PS amplitude)and its long-term potentiation (LTP) in the dentate granule gyrus. Results: LBP (30,60 mg·kg -1 ip) could increase the amplitude of hippocampal θ activity, but could not influence the basal transmission and PS amplitude of LTP or pEPSP slope of LTP induced by a weak (60Hz,30 pulses)or strong (10 bursts of 5 pulses, pulse frequency 400Hz,inter-bust interval 200ms) conditioned stimulation at dosages of 15-120mg·kg -1 .Also, 120mg·kg -1 dosage LBP could not potentiate the hippocampal θ activity. Conclusion:LBP can enhance the spontaneous electric activity of hippocampus, implying therefore that LBP could potentiate the cognition ability