Effects of repeated NPY or Veh treatment on electrophysiological properties of BLA PNs in brain slices taken at 2W and 4W after initiation of treatment. Data are represented as mean ± SEM. Numbers of individual neurons tested are indicated in each bar. A, Effect on resting membrane potential (RMP; 2W: t(79) = 3.57, p = 0.0006; NPY: n = 28 cells/24 rats, Veh: n = 53/17 and 4W: t(107) = 3.86, p = 0.0002, NPY: n = 61/30 Veh: n = 48/22). B1, Effect on rheobase (2W: t(68) = 2.16, p = 0.034; NPY: n = 26/16 Veh: n = 44/25 and 4W: t(95) = 1.98, p = 0.04; NPY: n = 43/22, Veh: n = 54/32). B2, Representative current-clamp recording depicting rheobase measurement as magnitude of ramp current (arrow) required to induce action potential firing from rest in a 2W Veh-treated neuron. C, Effect of acute NPY (1 μm) application on RMP as indicated (2W-Veh: t(14) = 2.73, p = 0.016; 2W-NPY: t(11) = 3.44, p = 0.0055; 4W-Veh: t(11) = 2.30, p = 0.042, 4W-NPY: t(14) = 0.54, p = 0.60). Data from 12 rats in each group are shown (ANOVA with Bonferroni's multiple-comparisons test F(3,50) = 2.30, p = 0.089). D, Effect of acute CRF (30 nm) application on RMP as indicated (2W-Veh: t(27) = 5.30, p = 1.35e-5; 2W-NPY: t(12) = 3.20, p = 0.0076; 4W-Veh: t(19) = 4.77, p = 0.0001, 4W-NPY: t(16) = 3.595, p = 0.0024). Data from 9–17 rats in each group are shown (ANOVA with Bonferroni's multiple-comparisons test F(3,74) = 0.96, p = 0.42). A, B, Unpaired t tests; C, D, paired-t tests. *p < 0.05, **p < 0.01, ***p < 0.001, ****p < 0.0001.