A, representative recording traces show changes in evoked NMDAR-EPSCs of lamina II neurons during baseline control, bath application of 0.6 μm Ro25-6981, and bath application of 5 μm AP5 plus 0.6 μm Ro25-6981 from one vehicle-treated rat and one FK506-treated rat. B, mean changes in the amplitude of NMDAR currents of lamina II neurons during baseline control, bath application of 0.6 μm Ro25-6981, bath application of 5 μm AP5 plus 0.6 μm Ro25-6981, and washout in vehicle-treated (n= 11 neurons) and FK506-treated (n= 9 neurons) rats. *P < 0.05 compared with the baseline control. #P < 0.05 compared with Ro25-6981 alone.