Fig. 1.

Effects of chronic cyclic stretch (CS) on TNF-α-induced endothelial cell (EC) barrier dysfunction. Human pulmonary artery ECs (HPAECs) grown on Flexcell plates were subjected to 18% CS, 5% CS, or static conditions (ST) for 24 h followed by TNF-α (20 ng/ml, 4 h) stimulation. A: cytoskeletal remodeling in static and stretched ECs was examined by immunofluorescence staining for F-actin; paracellular gaps are marked by arrows. B: quantitative analysis of paracellular gap formation in control and TNF-α-stimulated HPAECs with or without 5% CS or 18% CS preconditioning. Data are expressed as means ± SD; n = 3, *P < 0.05 vs. static. C: soluble ICAM1 (sICAM1) content in preconditioned media was determined using an ELISA assay; n = 4, *P < 0.05 vs. static.