Enhanced production of endothelium-derived contracting factor by endothelial cells subjected to pulsatile stretch

The purpose of this study was to assess the role of cyclic deformation in modulating the production by endothelial cells (ECs) in culture of a recently described endothelium-derived smooth muscle cell contracting factor, endothelin. We grew bovine aortic ECs to confluence on culture plates with flexible membrane bottoms. Vacuum (-20 kPa) was applied to deform the membrane to 24% strain at 60 cycles/min for 1, 3, or 5 days. Control ECs were grown on the same membrane but without vacuum deformation. The conditioned media were collected, centrifuged at 10,000 rpm for 10 minutes to remove cells and debris, and the supernatant fluid was subjected to radioimmunoassay for endothelin. The results demonstrate that bovine aortic ECs release a basal level of endothelin under stationary conditions (107.1 +/- 14.7 pg/10(5) cells), and this production increased fivefold to sixfold with cyclic stretch. Thus physical forces exerted on ECs in culture can influence the secretion of this vasoconstrictive molecule.