Figure 8.

Layer 2/3 pyramidal neurons of floxed NR1 mice transduced with lentivector encoding GFP and Cre have deficits in pairing-induced synaptic potentiation. (A) EPSCs were evoked at 1 Hz by extracellular stimulation in layer 4 and recorded in layer 2/3 pyramidal neurons while voltage-clamping the somatic membrane potential at −60 mV. After 200 seconds of baseline EPSCs, the membrane potential was depolarized to 0 mV while stimulation continued. The membrane potential was returned to −60 mV and the effects of the pairing observed. In this GFP-negative control neuron, the amplitude of the evoked EPSCs was increased by the pairing, indicating potentiation of synaptic transmission. (B) The same pairing protocol was applied to a GFP-positive NR1 knockout neuron, but in this case pairing did not result in an increased EPSC amplitude. (C) The degree of pairing-induced synaptic potentiation was quantified as the ratio of EPSC amplitude after pairing compared to that observed before pairing. GFP-positive NR1 KO neurons were significantly deficient in pairing-induced synaptic potentiation compared to GFP-negative control neurons (n = 11 of each type, GFP-positive and GFP-negative).