Fluidization, resolidification, and reorientation of the endothelial cell in response to slow tidal stretches.
Mechanical stretch plays an important role in regulating shape and orientation of the vascular endothelial cell. This morphological response to stretch is basic to angiogenesis, neovascularization, and vascular homeostasis, but mechanism remains unclear. To elucidate mechanisms, we used cell mapping rheometry to measure traction forces in primary human umbilical vein endothelial cells subjected to periodic uniaxial stretches. Onset of periodic stretch of 10% strain amplitude caused a fluidization response typified by attenuation of traction forces almost to zero. As periodic stretch continued, the prompt fluidization response was followed by a slow resolidification response typified by recovery of the traction forces, but now aligned along the axis perpendicular to the imposed stretch. Reorientation of the cell body lagged reorientation of the traction forces, however. Together, these observations demonstrate that cellular reorientation in response to periodic stretch is preceded by traction attenuation by means of cytoskeletal fluidization and subsequent traction recovery transverse to the stretch direction by means of cytoskeletal resolidification.
Center for Vascular Biology Research, Harvard Medical School, Boston, Massachusetts, USA.
Ramaswamy
R
Krishnan
Elizabeth Peruski
EP
Canovic
Andreea L
AL
Iordan
Kavitha
K
Rajendran
Greeshma
G
Manomohan
Athanassios P
AP
Pirentis
Michael L
ML
Smith
James P
JP
Butler
Jeffrey J
JJ
Fredberg
Dimitrije
D
Stamenovic
D002478:Cells, Cultured; D003599:Cytoskeleton; D042783:Endothelial Cells / Q000166:cytology* / Q000502:physiology*; D005786:Gene Expression Regulation / Q000187:drug effects / Q000502:physiology; D061307:Human Umbilical Vein Endothelial Cells / Q000166:cytology; D006801:Humans; D040542:Mechanotransduction, Cellular / Q000502:physiology*; D012212:Rheology; D015398:Signal Transduction / Q000187:drug effects / Q000502:physiology; D013314:Stress, Mechanical; D013997:Time Factors; D054460:rho-Associated Kinases / Q000235:genetics / Q000378:metabolism
D054460:rho-Associated Kinases