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目的：从突触水平检验不同浓度的阿斯巴甜对果蝇中枢神经元影响及作用机制，为进一步探究阿斯巴甜生物安全性提供支持。方法采用膜片钳全细胞记录的方法，通过离子通道的阻断与分离，分别记录给药前后果蝇投射神经元（PN）的胆碱能突触微小兴奋性电流（mEPSC）、钙离子通道电流和钙通道瞬时电流密度，统计并分析mEPSC幅值和频率，以及钙通道电流峰值和瞬时电流密度。结果与给药前相比，8μg／ml阿斯巴甜会降低果蝇PN的mEPSC频率（t＝22．05，P＜0．01）、钙电流峰值（t＝5．01，P＜0．01）和瞬时电流密度（t＝2．68，P＜0．05）；2μg／ml阿斯巴甜会降低果蝇PN的mEPSC频率（t＝3．15，P＜0．05），其他实验指标差异则无统计学意义（P＞0．05）。结论一定浓度的阿斯巴甜可影响果蝇中枢投射神经元的电活动，并且该作用可能是通过影响钙电流而实现的。“,”Objective To study the effect of different concentrations of aspartame in Drosophila central nervous system , especially to the electrical activity of projection neuron (PN), and evaluate the biological security of aspartame and neural mechanism. Methods The whole-cell electrophysiological signals of projection neurons in Drosophila was detected by patch clamp. The recordings of mini excitatory postsynaptic currents (mEPSC) and calcium currents were performed in both pre-and post-of aspartame treatment. Results Aspartame treatments with 8 μg/ml could reduce the frequency of mEPSC (t=22.05, P<0.01), calcium currents peak (t=5.01, P<0.01) and instantaneous current density (t=2.68, P0.05) at the same time. In addition, there have no statistically significant in aspartame treatments with 2μg/ml experimental groups except for the frequency of mEPSC (t=3.15, P<0.05). Conclusion There has a range of aspartame concentration can significantly affect the electrical activity of projection neurons in Drosophila central nervous system, which could be effective via the calcium channel.