外侧隔—海马CA1通路电生理分析

电刺激外侧隔区可在海马 CA1区锥体细胞层记录到群锋电位,在 CA1辐射层顶树突记录到兴奋性突触后电位(EPSP)。侧脑室注射微量海人酸损毁海马 CA3-CA4区锥体细胞后,电刺激外侧隔区在 CA1顶树突不再诱发 EPSP,由此认为外侧隔-CA1顶树突的神经联系是通过同侧海马 CA3锥体细胞侧支实现的。但 CA3-CA4损毁后,电刺激外侧隔区在海马 CA1起层锥体细胞底树突仍可记录到 EPSP。这一在正常情况下被掩盖的外侧隔-CA1底树突神经联系及其来源尚有待探讨。

AN ELECTROPHYSIOLOGICAL ANALYSIS OF PATHWAYS FROM LATERAL SEPTUM TO HIPPOCAMPAL CA1 AREA IN RAT

Upon stimulating the lateral septal region,a population spike could be re-corded in the stratum pyramidale of hippocampal CA1 together with a recordableEPSP in the apical dendrites(stratum radiatum).After destruction of hippocam-pal CA3,CA4 pyramidal cells by intraventricular microinjection of kainic acid,electricai stimulation of the lateral septum could no longer evoke EPSP in the api-cal dendrites.This experiment suggests that the neural connection of the lateralsepto-CAl apical dendrites is mediated by the collaterals of the ipsilateral CA3pyramidal cells.But after the destruction of CA3,CA4,electric stimulation oflateral septum could still evoke EPSP in the basal dendrites(stratum oriends).The neural connection mediating the response of the lateral septo-CAl basal den-drites was not reported before,but the neural pathway remains to be investigated.