Endothelial Cell-Derived SO₂ Controls Endothelial Cell Inflammation, Smooth Muscle Cell Proliferation, and Collagen Synthesis to Inhibit Hypoxic Pulmonary Vascular Remodelling

Figure 1

Increased EC-derived SO₂ ameliorates hypoxia-induced PH. (a) Immunofluorescence in situ detection of AAT1 protein expression in mouse PAECs. Green fluorescence represents AAT1 protein, and red fluorescence represents vWF, a marker for ECs; the nuclei were stained with DAPI. (b) HPLC method was performed to detect SO₂ content in mouse lung tissue (). (c) Western blot analysis was carried out to detect the expression level of AAT1 protein in HPAECs (). (d) Red SO₂ fluorescent probe method was used to determine the SO₂ level in HPAECs, and the nuclei of HPAECs were stained with DAPI. (e, f) Catheter method was performed to detect mouse right ventricular systolic pressure (RVSP) (). (g, h) The ratio of pulmonary acceleration time (PAT) to pulmonary ejection time (PET) of the mouse pulmonary artery blood flow was measured using ultrasound (). (i, j) HE and Hart’s methods were used to detect PVR in mice. (k) Hart’s method was conducted to analyze the degree of muscularization of small pulmonary vessels in mice (); NMV: nonmuscular vessels; PMA: partial muscular arteries; MA: muscular arteries. The data were expressed as , , scale bar: 20 μm.

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