Fig. 4. Concentration–response curves of the effects of DADLE on AMPA receptor–mediated and NMDA receptor–mediated EPSCs. (A ) Semilogarithmic plot of the relative inhibition of the AMPA–EPSC amplitudes as a function of the DADLE concentration. (B ) Semilogarithmic plot of the relative inhibition of the two components of the NMDA–EPSC amplitudes as a function of the DADLE concentration. In both plots, the data points could be fitted by sigmoid functions. Data are expressed as mean ± SEM.