Figure 2. Ca²⁺-impermeable AMPA receptors are involved in mediating ipRGC-driven EPSCs of DACs. The α-amino-3-hydroxyl-5-methyl-4-isoxazole-propionate (AMPA) receptor-mediated light-induced excitatory postsynaptic currents (EPSCs) of dopaminergic amacrine cells (DACs) were recorded in the presence of a cocktail of antagonists (see Figure 1) from retinas of Opn4-function-only TH::RFP mice. The DAC light-induced EPSCs were unchanged in the presence of 5 µM PhTX. A representative recording is illustrated in (A). Average data (mean ± standard error of the mean (SEM)) are shown in (B; n=7, n.s. p>0.05, paired t test). In contrast, 30 µM GYKI53655 almost completely blocked the DAC light-induced EPSCs (C). Average data (mean ± SEM) are shown in (D; n=7, p<0.001, paired t test). The DAC light-induced EPSCs stimulation bar shows the timing of a 470 nm light pulse (duration: 3 s; intensity: 4.7 × 10¹³ photons·cm⁻²·s⁻¹).