Figure 3.

Time-dependent effects of actinomycin D (30 μM, A) and effect TGF-β (1 ng·mL⁻¹, 1 h) in absence and presence of actinomycin D (Act, present 15 min before TGF-β, B) on expression of prepro-ET-1 (ppET-1) in MRC-5 human lung fibroblasts. After dissemination, cells were cultured for 24 h in presence of 10% FCS followed by up to 4 h in presence of 1% FCS and absence or presence test drugs. Thereafter, total RNA was isolated, treated with DNase and used for quantitative real time PCR. Ordinate (A) and height of columns (B): ppET-1 mRNA (ΔC_t over GAPDH) is expressed as % of the control of the individual cell preparation, given are means ± SEM of n ≥ 4. Significance of differences: ***P < 0.001 versus Ctr.; ⁺⁺⁺P < 0.001 versus value in presence of TGF-β alone; ns, not significant versus Act alone.