Figure 11.

Postnatal remodelling of the pulmonary vasculature in HO-1 deficient mice. Lung tissue from 3–5-day-old and 14-day-old (Hmox1^+/+ and Hmox1^−/−) mice was fixed in 10% formol saline, embedded in paraffin wax, sectioned (4 μm) and stained using an antibody specific for smooth muscle α-actin (dilution 1 : 3000) using the streptavidin–biotin–peroxidase complex method. Images were captured using a Zeiss AxioCam and analysed using Openlab. The external and internal areas of muscular and partially muscular pulmonary arteries were measured. Percentage medial wall area was then calculated. The figure shows the percentage medial wall thickness from (a) 3–5-day-old Hmox1^+/+ (11–52 vessels from n=4 animals were analysed) and Hmox1^−/− (14–52 vessels from n=6 animals were analysed) mice and (b) 14-day-old Hmox1^+/+ (17–52 vessels from n=4 animals were analysed) and Hmox1^−/− (14–43 vessels from n=3 animals were analysed) mice. Data are mean±s.e.m. No significant difference (two-way ANOVA) was observed between the Hmox1^+/+ and Hmox1^−/− mice in either age group.