title: Effect of flow direction on the morphological responses of cultured bovine aortic endothelial cells.
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 degrees with a large S.D. value. Endothelial cells can be expected to recognise the flow direction, and change their shape and F-actin structure.
authors.affiliation: Graduate School of Mechanical Engineering, Tohoku University, Miyagi, Japan.
authors.forename: N
authors.initials: N
authors.lastname: Kataoka
authors.forename: S
authors.initials: S
authors.lastname: Ujita
authors.forename: M
authors.initials: M
authors.lastname: Sato
mesh_terms: D000199:Actins / Q000378:metabolism; D000818:Animals; D001011:Aorta; D002417:Cattle; D018929:Cell Culture Techniques; D048429:Cell Size; D002478:Cells, Cultured; D004730:Endothelium, Vascular / Q000166:cytology* / Q000378:metabolism; D013314:Stress, Mechanical
chemical_list: D000199:Actins