Vhlfl/fl mice also carrying no Cre or LysM-Cre were maintained in normoxia for 49 days after birth. (A) BALF was isolated and Pdgfb transcript levels were measured by qRT-PCR. (B) Lung vibratome sections of L.L1.A1.L1 region were stained for SMA and MECA-32 with boxed regions magnified below. RVSP (C) and Fulton index (D) are shown. (E) Lung vibratome sections were stained for SMA, CD64, and nuclei (DAPI), with arterioles labeled with “a.” Boxed regions shown are shown below as close-ups, and the number of macrophages (asterisks) quantified per 100 alveoli (F). More than 500 alveoli per mouse were quantified. n = 3 mice. Student’s t test was used in A, C, D, and F. Scale bars: 25 μm.