Abstract
The effect of flow direction on the morphology of cultured bovine aortic endothelial cells is studied. Fully confluent endothelial cells cultured on glass were subjected to a fluid-imposed shear stress of 2 Pa for 20 min and 24 h using a parallel plate flow chamber. Experiments on shear flow exposure were performed for (i) one-way flow, (ii) reciprocating flow with a 30 min interval and (iii) alternating orthogonal flows with a 30 min interval. After flow exposure, the endothelial cells were fixed and F-actin filaments were stained with rhodamine phalloidin. Endothelial cells were observed and photographed by means of a microscope equipped with epifluorescence optics. The shape index (SI) and angle of cell orientation were measured, and F-actin distributions in the cells were statistically studied. Endothelial cells under the one-way flow condition showed marked elongation (SI=0.39±0.16, mean±S.D.) and aligned with the flow direction. In the case of the reciprocating (SI=0.63±0.14) and the alternating orthogonal flows (0.64±0.14), cells did not elongate so strongly as in the case of one-way flow. Although most cells in the reciprocating flow aligned with the flow direction, the cell axes in the alternate orthogonal flow distributed around a mean value of −45.1° with a large S.D. value. Endothelial cells can be expected to recognise the flow direction, and change their shape and F-actin structure.
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Kataoka, N., Ujita, S. & Sato, M. Effect of flow direction on the morphological responses of cultured bovine aortic endothelial cells. Med. Biol. Eng. Comput. 36, 122–128 (1998). https://doi.org/10.1007/BF02522869
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DOI: https://doi.org/10.1007/BF02522869