Estradiol (E2) effects on transmission do not depend on brain-derived neurotrophic factor (BDNF) or TrkB signaling. (a) TrkB-Fc (2 μg/ml; at horizontal bar) blocked Schaffer-commissural (S-C) long-term potentiation (LTP) induced with theta burst stimulation (TBS) applied at 30 min (t(12)=3.83, p=0.002 vs veh at 55–60 min post-TBS; two-tailed t-test). (b) TrkB-Fc did not influence E2's effects on synaptic responses (t(9)=0.510, p=0.623 vs veh; two-tailed t-test). (c) The percentage of postsynaptic density 95-positive (PSD95+) elements colocalized with dense pTrkB-ir was similarly elevated in slices treated with E2 or E2+TrkB-Fc, relative to vehicle (veh) control values (F(2,22)=12.4, p=0.0002, one-way analysis of variance (ANOVA); ***p<0.001 vs veh; Bonferroni's post hoc test). (d) ANA-12 (750 nM) did not block E2's effects on transmission (t(10)=0.25, p=0.81 vs veh; two-tailed t-test). Numbers within parentheses and on bars denote the number of slices per group. A full color version of this figure is available at the Neuropsychopharmacology journal online.