Figure 6.

N-methyl-d-aspartic acid receptor blockade reveals that increased GABAergic conductance at the unpaired pathway underlies the pathway specificity of disinhibition-mediated LTP. (Ai) Example recording of the PSP amplitude plotted against V_m for the paired pathway before and after pairing. (Aii) Sample traces before and after pairing for the same cell as in (Ai). (Bi) Example recording of the PSP amplitude plotted against V_m for the unpaired pathway before and after pairing. (Bii) Sample traces before and after pairing for the same cell as in (Bi). (Ci) Summary of the change in mixed PSP amplitude, measured from the resting membrane potential, at the paired and unpaired pathways with NMDARs antagonized (n = 6). (Cii) Summary of the change in mixed PSP amplitude, measured from the initial PSP reversal potential, at the paired and unpaired pathways with NMDARs antagonized [for the same cells as in (Cii)]. Blue triangles denote paired pathways, red triangles denote unpaired pathways; filled triangles represent baseline recordings, open triangles represent recordings following plasticity induction. PSP–V_m curves were constructed at five time points, alternating between unpaired and paired pathways. Each of the five time points at the paired pathway were compared to the corresponding time point from the unpaired pathway. * Denotes statistical significance from unpaired pathway (p < 0.05). † Denotes statistical significance from baseline (p < 0.05). Paired activity denoted by arrow.