A, bath application of CNO (10 μM) significantly attenuated the magnitude of LTP induced by 5× HFS in BLA principal neurons transfected with hM4D Gi-coupled DREADD receptors (n = 5, stars). B, conversely, bath application of CNO facilitated the induction of LTP by a sub-threshold stimulation protocol (2× HFS) in BLA principal neurons transfected with rM3D Gs-coupled DREADD receptors (n = 5, stars). Upper traces in A and B are representative EPSPs evoked before and after CNO application.