Effects of SAHA on IFN-γ-induced phosphorylation of STAT1 and STAT3 in human astrocytes. Human astrocytes were incubated with or without SAHA at the concentrations indicated for 1 h. The cells were subsequently stimulated with IFN-γ for 30 minutes. Astrocytes in the control group were incubated with medium only. Cell lysates were separated by 8% SDS-PAGE and immunoblotted for phospho-Tyr701-STAT1 (pSTAT1) and total STAT1 (A) or phospho-Tyr705-STAT3 (pSTAT3) and total STAT3 (C). The density ratios of phosphorylated to total protein are shown as mean ± S.E.M. of three independent experiments (B, D). *Significantly different from IFN-γ stimulation only.