TNFα, unlike other cytokines, acts on neurons to increase surface expression of AMPARs. A, Representative micrographs from sister cultures of nonpermeabilized isolated neurons immunostained for surface expression of the AMPA subunit GluR1. The cells on the right were treated with 60 nm TNFα for 15 min. B, Group data from untreated or TNFα-treated cultures (n = 70 for both conditions), showing a substantial increase in surface GluR1 staining. C, Composite data of surface GluR1 from cultures treated with TNFα (60 nm; n = 214), IL-1β (50 ng/ml; n = 140), IL-6 (32 ng/ml; n = 159), or IL-10 (40 ng/ml; n = 130). D, Group data of surface GluR1 from cultures treated for 24 h with sTNFR (10 μg/ml; n = 59) or an antibody against IL-1β (40 μg/ml; n = 72). For this and all subsequent figures, ^*p < 0.05; ^**p < 0.001; ^***p < 0.0001 when compared with untreated cultures.