Figure 7.

CH increases ET-1–induced O₂⁻ production in pulmonary arterial smooth muscle cells through EGFR. Digitally inverted representative images and mean fluorescence intensity (MFI) of dihydroethidium (DHE) fluorescence in thresholded images of pulmonary arterial smooth muscle cells from CH and control rats. Cells were treated with vehicle, ET-1 (10⁻⁸ M), or ET-1 plus the EGFR inhibitor AG1478 (1 μM). Cells were isolated from intrapulmonary arteries (second–fifth order) and transiently cultured (3–4 d) before study (18, 19). MFI was averaged from five images/sample (one rat/sample). Each image was thresholded to select for positively stained areas above background. Values are mean ± SE of n = 4–7 rats/group. Scale bar: 20 μm. *P < 0.05 versus control ET-1. ^#P < 0.05 versus CH vehicle. ^τP < 0.05 versus CH ET-1.