TNFα signals through neuronal TNFR1 to downregulate GABAergic neurotransmission. A, Representative dendritic regions of surface immunostaining for GABAAR γ2 subunit, from untreated (Ctrl) or TNFα-treated cultured neurons, preincubated with either TNFR1 neutralizing antibody (R1nAb) or TNFR2 neutralizing antibody (R2nAb). Scale bar, 3 μm. B, Quantification data of γ2 cluster area corresponding to conditions in A, showing that blocking TNFR1 function blocks the effects of TNFα (gray bars), whereas blocking TNFR2 does not (n = 135–191 images in each condition; two-way ANOVA, Bonferroni's post hoc test, *p < 0.05, ***p < 0.001; n.s., not significant). C, Representative traces of mIPSC recordings from untreated (Ctrl) or TNFα-treated WT or TNFR1−/− neurons cocultured with WT glia or TNFR1−/− glia. D, Group data of average mIPSC amplitude indicating that TNFα-induced downregulation is absent from TNFR1−/− neurons cocultured with WT glia but present in WT neurons cocultured with WT or TNFR1−/− glia (n = 12–22 cells in each condition; two-way ANOVA, Bonferroni's post hoc test, *p < 0.05, **p < 0.01; n.s., not significant).