In similar experiments, either NR2A or NR2B inhibitor, i.e. NVP or Ro/Ife, was applied just after the first tetanus (Fig. 5B, C, Fig. 6A values marked b-c), assuring that the drug did not affect induction of the first LTP whereas it had access to all the following plasticity. This evidence concerns the gene GRIN2B and tetanus.