【作者】 蒋文高；

【导师】 莫宁；

【作者基本信息】 广西医科大学 ， 神经药理学， 2003， 硕士

【摘要】 目的：研究银杏叶提取物（EGb761）对离体大鼠颈上神经节烟碱传递过程的影响。方法：应用细胞内生物电记录技术。结果：EGb761在10-6～10-1g/L的浓度灌流神经节1～10分钟，可逆性的部分或完全抑制42个实验细胞的快兴奋性突触后电位（f-EPSP），其中38个细胞不伴有膜电位的改变，4个细胞伴有膜的缓慢除极化，膜电位恢复到原水平时，抑制作用仍然存在；10-6～10-1g/L的EGb761单独灌流24个细胞1～10分钟，21个细胞的膜电位无变化，2个细胞轻度除极化和1个细胞发生先超极化后除极化的双向反应；2.0～3.5×10-1g/L的EGb761灌流（n=10）使细胞膜发生除极化（n=7），无变化（n=2）和超级化（n=1）的反应；膜电阻均无可测性改变；10-1g/L的EGb761不影响乙酰胆碱（Ach）和氨甲酰胆碱（Carb）引起的膜除极化反应。结论：10-6～10-1g/L的EGb761对离体大鼠颈上神经节突触烟碱传递的抑制作用与突触前机制有关，可能抑制了突触前膜的钙离子内流，从而减少了Ach递质的释放，使f-EPSP的幅度减小甚至消失更多还原

【Abstract】 Object: To study the effects of EGb761 on nicotinic transmission in the isolated superior ganglia of the Wistar rats. Method: Intracellular recording technique. Results: At the concentractions of 10-6~10-1g/L for 1~10minutes, EGb761 can reduced or cancelled the amplitude of the fast excitarory postsynaptic potential(f-EPSP) induced by the single stimulation of the preganglionic sympathetic trunk (n=42),with the memberane potentials of 38 cells unchanged and the memberane of 4 cells depolarized moderately; When the memberane potentials return to the base line,the inhibition effects of EGb761 on f-EPSP still existed.During the 1~10 minutes of perfusion with EGb761(10-6~10-1g/L, n=24),the memberane potentials of 21 cells weren’t alerted,two cells has slight depolarization,and one depolarized after hypolarized. When perfused with EGb761(2.0~3.5×10-1g/L,n=10), 7 cells depolarized moderately,2 cells unchanged, and one hypolarized. The memberane resistance were not significantly alerted at both concentrations. EGb761 have no effects on the depolarization by exogenous acetycholine(Ach) and carbachol(Carb). EGb761(10-1g/L) antagonized the facilitation of high Ca2+(5mmol/L) Kerb’s solution on the f-EPSP, and enhanced the depressant effect of low Ca2+ Kerb’s solution.Conclusion:EGb761 can inhibited reversedly the nicotinic transmission at superior cervical ganglia probably by presynaptic mechanism, relating to the inhibition of the Ca2+ influx更多还原