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中枢神经元至少有三种谷氨酸受体亚型,它们选择性地由谷氨酸结构类似物 N-methyl-D-aspartate(NMDA)、quisqualate 和 kainate 激活。NMDA 与其受体作用后可使 Na~+、K~+及 Ca~(2+)离子通透性增加,同时记录到40～50pS、5ms 的电导水平,Mg~(2+)离子可将其选择性阻断;而 quisqualate 和 kainate 与其受体作用后,仅 Na~+、K~+离子通透性增加,Ca~(2+)离子通透性无变化,此时记录到1～20pS,0.5ms 电导(kainate 引起的电导偏小),Mg~(2+)离子对其无作用。由于 NMDA,quisqualate 和 kainate 与各自的受体作用后引起不同的离子通透性、不同的电导水平,它们对 Mg~(2+)有不同的敏感性,因而传统上认为,谷氨酸受体的不同亚型有不同的离子通道。
Central neurons have at least three subtypes of glutamate receptors that are selectively activated by the glutamate structural analogues N-methyl-D-aspartate (NMDA), quisqualate and kainate. The permeability of Na ~ +, K ~ + and Ca ~ (2+) ions increased with NMDA and its receptor, and the conductivity of 40 ~ 50pS and 5ms was recorded at the same time. While quisqualate and kainate reacted with their receptors, only the permeability of Na ~ + and K ~ + ions increased and the permeability of Ca ~ (2+) ions did not change. At this time, 1 ~ 20pS was recorded, 0.5ms conductance (kainate induced conductivity is too small), Mg ~ (2 +) ions have no effect on it. Since NMDA, quisqualate and kainate cause different ion permeability after acting on their respective receptors, they have different sensitivities to Mg 2+ due to their different conductance levels. Therefore, it has been traditionally believed that glutamate receptors Different subtypes have different ion channels.