MORPHOLOGICAL-CHANGES OF ENDOTHELIAL-CELLS AFTER EXPOSURE TO FLUID IMPOSED SHEAR-STRESS - DIFFERENTIAL RESPONSES INDUCED BY EXTRACELLULAR MATRICES

Effects of extracellular matrices (ECMs) and fluid-imposed shear stres s on the cell shape and the cytoskeletal structure of microfilaments w ere studied in cultured porcine aortic endothelial cells (PAECs). The PAECs were. cultured until confluent on non-coated or on ECM-coated gl ass coverslips. The components of ECM used were type IV collagen, hepa ran sulfate, chondroitin sulfate and dermatan sulfate. The PAECs cultu red on the mixed ECMs showed marked elongation and segmental orientati on with randomly distributed cell axis even under a no-flow static con dition, and the microfilaments were mostly observed in parallel with t he cell axis. After shear flow exposure (2 Pa, 24-48 hrs), the PAECs o n non-coated glass were significantly elongated and oriented to the fl ow direction, however the PAECs on ECM-coated glass showed more retard ed responses than the ones on noncoated glass, indicating that the anc horage to the substrate was enhanced by ECMs. The stress fibers were r eorganized in accordance with the cell shape and oriented to the flow direction. These findings suggest that ECM may act together with shear stress to modify- and maintain the endothelial cell configuration.