Pharmacological properties of α7β2-nAChRs expressed in hippocampal CA 1 interneurons. A. A typical trace of inhibitory effects of selective α7-nAChR antagonist (MLA), or β2-nAChR antagonist (DHβE) on choline-induced whole cell currents recorded from a hippocampal CA1 interneuron (a) and a VTA DAergic neuron (b) at a holding potential of −60 mV. B. Analysis of concentration-inhibition curves of MLA shows that after pre-incubation for 2 min, 10 mM choline-induced whole-cell currents in hippocampal CA1 interneurons and VTA DA neurons were not significantly different (Ba). However, DHβE significantly inhibited choline-induced whole-cell currents from hippocampal CA1 interneurons but not those from VTA DA neurons (Bb, **p < 0.01, t-test).