Fig. 8.
Localization of ETA and ETB receptors in alveolar macrophages and macrophages in close proximity to small blood vessels in HPAH and control lungs. Lung macrophages were identified using the macrophage antibody (Ab) 25F9 (FITC labeled), and localization of ETA and ETB receptors was identified using either ETA or ETB receptor Ab (Cy3 labeled). DAPI was used as the nuclear stain. In control lungs, ETA receptors localize in alveolar macrophages close to small vessels (A–D). In contrast, ETA receptor localization is reduced in lung macrophages surrounding the small vessels in HPAH lung tissue (E–H). Similarly, ETB receptors localized to lung macrophages in close proximity to small pulmonary arteries in control lung (I–L), and ETB expression was reduced in HPAH lungs (M–P). Magnification, ×400.