Smooth muscle cell migration induced by shear-loaded platelets and endothelial cells. Enhanced platelet-derived growth factor production by shear-loaded platelets.
BACKGROUND
Uncontrolled migration and proliferation of smooth muscle cells (SMC) are the main mechanisms of development of atherosclerotic neointima. However, it has not yet been elucidated how mechanical stress is involved in this process. We investigated smooth muscle cell mitogenic activity induced by shear-loaded platelets and endothelial cells.


METHODS



METHODS
in vitro experimental study. We devised four types of conditioned media; supernatant of mixed culture of platelets and endothelial cell (ST), supernatant of shear-loaded mixed culture of platelets and endothelial cell (SH), ST medium neutralised with anti-PDGF antibody (ST+), and SH medium neutralised with anti-PDGF antibody (SH+). Smooth muscle cells were cultured in each conditioned medium, and their spreading activity was determined under a microscope.


RESULTS
Smooth muscle cells spreading activity in the SH group was significantly greater than that in the ST group. Their spreading activity was suppressed by anti-PDGF antibody under shear conditions (SH+), but it was not by anti-PDGF antibody under static conditions (ST+).


CONCLUSIONS
Our results demonstrate that platelet-derived growth factor is produced by shear-loaded platelets and endothelial cells, and local mechanical forces may play an important role in cardiovascular disease.
Nakazawa
T
T
Department of Surgery, The University of Tokyo, Japan.
Yasuhara
H
H
Shigematsu
K
K
Shigematsu
H
H
D001792:Blood Platelets / Q000502:physiology*; D002455:Cell Division; D002465:Cell Movement; D002478:Cells, Cultured; D004730:Endothelium, Vascular / Q000166:cytology / Q000502:physiology*; D018056:Hemorheology; D006801:Humans; D006965:Hyperplasia / Q000209:etiology; D066298:In Vitro Techniques; D009131:Muscle, Smooth, Vascular / Q000166:cytology* / Q000502:physiology; D010982:Platelet-Derived Growth Factor / Q000276:immunology / Q000378:metabolism*; D011673:Pulsatile Flow; D013314:Stress, Mechanical; D017539:Tunica Intima / Q000473:pathology
D010982:Platelet-Derived Growth Factor