Effects of shear stress on endothelial cell alignment.

(A–C) HUVEC layers electrochemically transferred to the internal surfaces of microchannels and cultured in chambers for 12 h in the presence or absence of culture medium perfusion. HUVECs were partially detached in the absence of perfusion (A, arrows), but continued to cover the surface at a flow rate of 1 μL/min (B) and 10 μL/min (C). Scale bars, 500 μm. (D–G) Quantification of HUVEC orientation with respect to flow direction after 12 h of culture in the presence or absence of perfusion. The angle and mean amplitude at 0 μL/min (D), 1 μL/min (E), and 10 μL/min (F), and comparisons of the orientation intensity (G). *P < 0.05, **P < 0.01. Error bars indicate standard deviations calculated from three independent experiments.