Figure 1.

Functional classes of iGluRs. (A) iGluRs are divided into AMPA, kainate, and NMDA receptors with multiple subunits cloned in each of these functional classes. (B) EPSCs from central synapses can be divided into fast AMPA or slow NMDA receptor–mediated components in the absence of Mg²⁺ using the AMPA receptor antagonist CNQX or the NMDA receptor antagonist AP5. The figure is adapted from Traynelis et al. (2010). (C) The relationships between NMDA receptor current response and membrane potential (i.e., holding potential) in the presence and absence of 100 µM extracellular Mg²⁺ reveal the voltage-dependent Mg²⁺ block, which is relieved as the membrane potential approaches 0 mV (i.e., with depolarization). Data are from Yi et al. (2018).