Fig. 3

Effects of foetal calf serum (FCS) and dexamethasone on apoptosis of cultured control rat PASMC. Representative Hoechst 33342 stained images from PASMC from control rats treated for 48–72 h with (a) 10 % FCS/DMEM as a negative control, (b) 800nM hydrogen peroxide (H₂O₂) as a positive control, (c) 0 % FCS and (d) 0 % FCS plus dexamethasone (10⁻⁷ M). Images are representative of 5–8 images per condition from n = 3–4 independent experiments per group at a magnification ×400. Data from these and other similar experiments inducing apoptosis by treating cells with dichloroacetate (DCA, 100 μM) and differing concentrations of H₂O₂ (100-800nM) for 48 h are quantified in (e). The effect of altering FCS concentrations on dexamethasone-induced apoptosis of PASMC at 48 h are shown graphically in (f) in cells from control rats. (g) The increased apoptosis observed by culturing cells with FCS and dexamethasone for 72 h rather than 48 h. Similar apoptotic responses to dexamethasone and FCS are seen in PASMC isolated from control and 21 day MCT-exposed rats (h). Results represent mean ± SEM from n = 3–5 per group, compared using 1-way ANOVA and Bonferroni’s post-test. *p < 0.05, **p < 0.01, ***p < 0.001