Effect of signaling pathway inhibitors on survival of cultured astrocytes. Primary cortical astrocytes were treated without or with different signaling pathway inhibitors used in this study (U 0126, 5 to 10 μM; SB 203580, 10 to 20 μM; BAY 11–7082, 10 to 20 μM; Ro 31–8220, 250 to 500nM; KT 5720, 250 to 500nM; SP 600125, 10 to 20 μM) for 24 hours and cell survival assessed by a colorimetric MTT assay. The optical densities were measured at 570 nm, with a 630 nm and blank correction. Data are normalized to percent of control (vehicle) and presented as Mean ± S.E.M of three independent experiments. P < 0.05, when compared to control.