Figure 4
Anti-mitogenic effects of PDE4 inhibition in PASMCs. Effects of PDE4 (cilomilast, rolipram, roflumilast) and PDE3 (cilostamide) inhibitors on PDGF-BB (5 ng/ml) stimulated DNA synthesis (A). Concentration-dependent effect of roflumilast, combined with a sub-maximal concentration of cicaprost, on [methyl-3H]-thymidine incorporation (B). Effect of roflumilast (10-6 M, open squares) on serum-stimulated (5% FBS) cell growth (closed squares) (C) and combined inhibitory effect of iloprost (10-7 M) after 10 days serum-stimulated growth (D). *, P < 0.05; **, P < 0.01; ***, P < 0.001 versus control cells stimulated with either PDGF-BB (A), cicaprost (B) or serum (C-D). Data represent mean ± SEM from four-six distinct isolates (A-B, D) and four replicates (C).