Morphological response of endothelial cells to combined pulsatile shear stress plus cyclic stretch

Endothelial cell (EC) function is regulated by the haemodynamic influence of shear stress and cyclic stretch. Using a specially constructed dynamic cell culture module (DCCM), the time-course effects of combined shear stress plus cyclic stretch on ECs were observed over a 48 hr period, including the effects of phase angle variation between the two stimuli. Shape analyses were performed on cell micrographs to quantify cell elongation and alignment. Compared to the effects of pulsatile shear alone, pulsatile shear plus cyclic stretch caused significantly more cell elongation after 12 hr (p<0.05) and more alignment after 24 hr (p<0.05) but there were no such differences after 48 hr. Also the cells responded faster to out of phase stresses with increased elongation by 3 hr (p<0.05), and increased alignment at 12 hours (p<0.01), but at 48 hr differences were longer present.