Fig. 1.

A: C57BL6 mouse. B: correlation between right ventricular systolic pressure (RVSP) and right ventricle (RV) to left ventricle (LV) plus septum (S) ratio (RV/LV+S) in mouse pulmonary hypertension (PH) models exposed to normoxia and hypoxia, compared with the combination of SU5416 and chronic hypoxia (SuHx) and monocrotaline (MCT)-injured rat models. C: correlation between RVSP and RV/LV+S in mouse models exposed to normoxia. Pearson coefficient 0.32, P = 0.150. D: correlation between RVSP and RV/LV+S in mouse models exposed to hypoxia. If all mouse models are included, the Pearson coefficient is 0.82, P = 0.0008. However, the correlation seems to be driven by an outlier, the IL6-OE mice (red dot). Thus, if the latter is not included in the statistical calculations, the coefficient becomes nonsignificant (r = 0.58, P = 0.057) (E). F: hematoxylin and eosin (HE)-stained lung section of a pulmonary vessel obtained from wild-type C57BL6 mice chronically exposed to ovalbumin. The mice develop severe pulmonary arterial muscularization without pulmonary hypertension. The vascular remodeling does not involve endothelial cell proliferation (G; brown staining is smooth muscle actin and blue is von Willebrand factor). F and G are reprinted from Daley et al. (2008), doi:10.1084/jem.20071008.