Figure 2.

AMPA and NMDA currents in WT and β₃-null dLGN cells. A, Representative maximal current traces at −70 mV (showing the fast inward AMPAR current) and +40 mV (showing the slowly decaying outward NMDAR current) at P10 and P15 in WT cells (black) and β₃-null cells (gray). Traces are normalized to the peak NMDAR current. B, Plot showing the mean and SEM maximal amplitude of AMPAR and NMDAR currents at P9–P11 and P15–P17 in β₃-null cells. Values are expressed relative to WT currents [mean (black dashed line) and SEM (light gray shading)]. Within each age group, the maximal currents for AMPARs and NMDARs were not different from those of WT cells. C, Plot of mean and SEM AMPAR/NMDAR current ratio at P9–P11 and P15–P17 for WT and β₃-null mice. For both groups, AMPAR currents strengthened with age. D, Representative NMDAR current traces at P10 and P16 for WT and β₃-null mice. Traces were normalized to the peak NMDAR current. E, Plot of mean and SEM NMDAR decay τ values (determined with a single exponential fit). For both groups, decay times were slower at P9–P11. *p < 0.001, both age groups vs condition. Responses in A and D were recorded in the presence of bicuculline, CGP, and nimodipine. β₃-null cells (WT cells): P9–P11 amplitude and ratio, 26 (21); τ, 37 (29); P15–P17 amplitude and ratio, 22 (19); τ, 35 (29).