Effect of mRNA and protein synthesis inhibitors on Dex-induced apoptosis and signaling pathway. Effect of actinomycin-D (Act-D; 2.5 μg/mL) and cycloheximide (CHX; 50 μg/mL) on (A) Dex-induced apoptosis, (B, left) DAG, (B, right) ceramide generation, and (C) CPP32 activity. Thymocytes were treated with Dex (10⁻⁷ mol/L) for the indicated times in the presence or absence of Act-D or CHX.