Figure 2. Hypoxia induced mitochondrial fragmentation and ER stress in PASMCs. (A) Ultrastructural alteration of the mitochondria and ER in pulmonary artery smooth muscle of normoxic and hypoxic rats. Scale bar, 500 nm. (B) Expression of mitochondrial dynamics-related proteins in endothelium-denuded pulmonary arteries. Twenty micrograms of protein was loaded in each lane. (C) Mitochondrial ROS detected by mitoSOX in isolated pulmonary arteries. Scale bar, 20 μm. (D) ER stress as assessed by CHOP expression in endothelium-denuded pulmonary arteries. Twenty micrograms of protein was loaded for each lane. *, p<0.05, **, p<0.01. n=8.