FIG 4.

Pulmonary hypertension in ePhd2^−/− mice is dependent on HIF-2. (A) Shown are HIF-1α (top) and HIF-2α (bottom) protein levels as detected by immunoblot analysis of nuclear pulmonary extracts from ePhd2^−/−Hif1a^−/− mice, ePhd2^−/− Hif2a^−/− mice, and their Cre⁻ littermate controls. Nuclear protein extracts from the kidney or liver of a PHI-treated mouse were used as positive controls (Ctrl). Ponceau staining was used to assess for equal protein loading. The graphs depict Pgk1 transcript levels in lungs from ePhd2^−/− Hif1a^−/− (n = 6) and ePhd2^−/− Hif2a^−/− (n = 5) mice. (B) RVSP and Fulton index in ePhd2^−/− Hif1a^−/− and ePhd2^−/− Hif2a^−/− mice. (C) Representative images of lungs stained for αSMA and quantification of muscularized vessels expressed as number/10 HPF in ePhd2^−/− Hif1a^−/−, ePhd2^−/− Hif2a^−/−, and control mice. Bars represent mean values ± SEM. *, P < 0.05; **, P < 0.01; ***, P < 0.001. Scale bar, 50 μm.