Fig. 3.

NE suppresses GABAergic inhibition of neurons in the LA by decreasing excitability of local circuit interneurons. (A) Representative sIPSPs in the LA neuron at a holding potential of −70 mV recorded with or without 10 μM NE in the bath solution. (B) Cumulative interevent interval histograms of sIPSCs recorded under baseline conditions (filled symbols) and after NE was applied (open symbols) (n = 16). (C) Summary plots of sIPSC and mIPSC (recorded in the presence of 1 μM Tetrodotoxin (TTX; n = 4) data (mean ± SEM). (D) Recording from interneuron that showed the nonaccommodating firing pattern in response to depolarizing current injection. (E) An outward current in the LA interneuron recorded under whole-cell conditions at a holding potential of −70 mV in the presence of 10 μM NE in the bath solution. (F) NE does not depress monosynaptic GABA_AR IPSCs in the LA. The IPSCs were recorded from pyramidal neurons at a holding potential of −70 mV (n = 4 cells). Stimulation pipette was placed within the LA. Traces (top) are averages of three IPSCs recorded before (1) and during (2) NE application. Synaptic currents were recorded in the presence of 20 μM 6-cyano-7-nitroquinoxaline-2,3-dione.