盐酸埃他卡林对大鼠海马神经元谷氨酸受体功能及突触活动的影响

目的: 研究盐酸埃他卡林(Ipt) 对脑神经元谷氨酸受体功能及突触活动的影响。方法: 采用原代培养的大鼠海马神经元, 应用膜片钳全细胞记录技术, 记录Ipt 对培养的海马神经元谷氨酸或天冬氨酸(NMDA) 诱发电流及神经元突触后电流的影响。结果: Ipt (1 ~ 100 μmol·L^-1) 可浓度依赖性地对抗培养的海马神经元谷氨酸或NMDA 诱发电流, 并为ATP敏感性钾通道拮抗剂格列本脲30 μmol·L^-1所对抗。Ipt 抑制培养的海马神经元之间突触联系形成的自发兴奋性突触后电流, 降低其发放频率, 抑制其电流幅度;但对微小兴奋性突触后电流无显著性影响。结论: Ipt 可阻断脑神经元谷氨酸受体功能, 抑制脑神经元谷氨酸的兴奋性突触传递, 其作用与ATP 敏感性钾通道相关。

Effects of iptakalim hydrochloride on glutamate receptors and spontaneous synaptic activities in rat hippocampal neurons

AIM: To investigate the effects of iptakalim hydrochloride (Ipt) on glutamate receptors and spontaneous synaptic activities in rat hippocampal neurons.METHODS: The cultured hippocampal neurons from neonatal rats were served as preparation.The effects of Ipt on glutamate receptors and spontaneous synaptic activities were observed by using whole-cell recording technique .RESULTS: Different concentrations of Ipt (1-100 μmol·L^-1) suppressed the glutamate and NMDA induced currents of rat hippocampal neurons in a dose-dependent manner, and these inhibitory effects were antagonized by K_ATP blocker glibenclamide (30 μmol·L^-1).Ipt inhibited the sEPSCs in cultured rat hippocampus neurons, and decreased both the frequency and amplitude, with no effect on mEPSCs.CONCLUSION: Ipt can block the function of glutamate receptor and attenuate the glutamatergic transmission in cerebral neurons, and these effects may be related with K_ATP.