Oxygen selectivity of the vasodilator effects in isolated human arteries.

<p>Riociguat (A) and sildenafil (B) relax human pulmonary arteries (PA) bubbled with 21% O₂-5% CO₂-74% N₂, 95% O₂-5% CO₂ or with 95% N₂-5% CO₂ (hypoxia). Arteries were initially stimulated with a cocktail of U46619 (30 nM), 5-HT (3 μM) and endothelin (3 nM) and, thereafter, the drugs were added in a cumulative fashion (all from 10^-9M to 10^-5M). Results are means ± SEM (n = 11 and 10 for riociguat and 7 and 6 for sildenafil). The parameters calculated from these curves and their statistical analysis are shown in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0191239#pone.0191239.t001" target="_blank">Table 1</a>.