Figure 1

(a) Transpulmonary pressure gradient in the enalaprilat group. Mean pulmonary artery pressure (Ppa) minus occluded pulmonary artery pressure (Ppao) at constant cardiac output in 10 dogs as the fractional inspired oxygen (FiO₂) was decreased from 0.4 to 0.1, before (base) and after administration of enalaprilat. (b) Hypoxic response in the enalaprilat group. Hypoxic response defined as the increase in the gradient between Ppa and Ppao measured at constant cardiac output in response to a reduction in FiO₂ from 0.4 to 0.1 at baseline (base) and after administration of enalaprilat in 10 dogs. In both panels the vertical bars indicate the standard error of the mean.