NR2B-NMDARs are not required for LTP induced by pairing protocol in area CA1. A. Schematic diagram of the pairing protocol. B. Pairing protocol, as indicated by the arrow, induced a significant LTP in CA1 pyramidal neurons (n = 6). Sample traces of EPSC are the averages of 7 consecutive responses recorded during 5–10 min and 25–30 min, respectively. C. Bath application of Ro25-6981 (0.5 μM) had no effect on the LTP (n = 5). D. Histogram showing the effect of Ro25-6981 on the LTP. p > 0.05 vs. control.