吗啡通过突触前机制抑制视上核神经元兴奋性突触传递

Presynaptic inhibitory action of morphine on excitatory synaptic transmission in rat SON neurons in brain slices

目的 研究吗啡对大鼠视上核神经元兴奋性突触后电流 (excitatory postsynaptic currents,EPSCs)的影响 ,并对其突触机制进行探讨 .方法 采用脑片膜片钳全细胞记录技术 ,在电压钳状态下 ,记录吗啡对大鼠视上核神经元 EPSCs和 m EPSCs(miniature EPSCs)的影响 .结果 2 0 μm ol· L- 1的吗啡可分别使大鼠视上核神经元的 EPSCs的频率下降6 5 % ,幅度减少 44 % ,m EPSCs频率下降 45 % ,幅度减少12 % .

AIM To observe the effects of morphine on the excitatory postsynaptic currents (EPSCs) and miniature EPSCs (mEPSCs) in rat supraoptic nucleus (SON) neurons and to determine its synaptic mechanism. METHODS Using whole cell voltage clamp recording technique in brain slices, the EPSCs and mEPSCs of rat SON neurons were recorded, respectively. RESULTS 20 μmol·L -1 morphine decreased the frequency of EPSCs and mEPSCs (EPSCs by 65%, mEPSCs by 45%), and decreased the amplitude of EPSCs by 44% in all SON neurons, but had no effect on the amplitude distribution of mEPSCs. CONCLUSION Morphine inhibits the excitatory transmissions via presynaptic mechanisms in SON neurons from rat brain slices.