Figure 5.

Calcineurin activation during cue extinction alters synaptic plasticity through a presynaptic mechanism. Following SA, rats received a cue-extinction (60 CS) session followed immediately by infusion with either CGA or Veh. Twenty-four hours later, ex vivo recordings were performed in the LA. A, Input/output curve demonstrating average evoked EPSC amplitude across various stimulation intensities. Intra-LA CaN activation by CGA reduces EPSC amplitude. B, CGA infusion significantly increases PPR. CaN activation by CGA does not significantly alter (C) AMPA–NMDA. Data are expressed as mean ± SEM; n in bars, number of rats (number of neurons). *p < 0.05. Insets, Sample average EPSC traces. Scale bars: 50 ms, 200 pA.