Fig. 2

Dexamethasone increases apoptosis in pulmonary artery smooth muscle cell (PASMC) layer in monocrotaline (MCT) and dexamethasone-treated rats. In-situ detection of DNA fragmentation was performed on lung sections from control rats and on lungs resected from rats 28 days following MCT, with and without dexamethasone treatment (5 mg/kg/day from day 14–28). Representative examples in (a) a control rat, (b) nuclease-positive cells in an MCT-treated rat (black arrow), (c) negative-stained cells (unfilled arrow) in a rat at day 28 following MCT and (d) in a rat at day 28 following MCT and dexamethasone treatment (showing positive stained cells, black arrow). Results are representative of n = 5 per group (for a, c and d). Slides are counterstained with eosin. Magnification ×200. Scoring was performed by an assessor blinded to the groups for percentage positive PASMC over total number of counted cells (e). Results represent mean ± SEM of n = 5 per group, compared using 1-way ANOVA and Bonferroni’s post-test., *p < 0.05 ***p < 0.001