Norepinephrine (NE)-induced LTD in the PFC is abolished by nVH-lesion. Figure A left shows the infralimbic region of the prefrontal cortex (dotted line circle) that was examined in this study. A and B show the schematic diagrams depicting the placement of recording and stimulating electrodes. Whole-cell EPSPs evoked by stimulating either the layer I/II (EPSPsuperficial) or layer VI cortical inputs (EPSPdeep) were recorded from layer V pyramidal neurons. C, A brief NE treatment (20 μM, 10-min) induced LTD of EPSPsuperficial in slices obtained from sham-operated rats. D, Note that similar NE treatment did not produce long-lasting change of EPSPdeep. E, F, NE failed to induce LTD of EPSPsuperficial and EPSPdeep in slices obtained from nVH lesion rats. * p < 0.05 vs. baseline EPSP before NE application. G, Using slices obtained from control rats, NE-LTD of EPSPsuperficial can be abolished by α-1 adrenergic receptor antagonist prazosin (10 μM). H, A short Tat-GluR23Y peptide, which is known to inhibit the endocytosis of AMPA receptor, was delivered to layer V pyramidal neurons recorded from slices of control rats through whole-cell recording. NE failed to induce LTD of EPSPsuperficial in peptide-treated neurons.