The effects of a shear flow on the uptake of LDL and acetylated LDL by an EC monoculture and an EC-SMC coculture.
To elucidate the mechanisms of localized genesis and development of atherosclerosis and anastomotic intimal hyperplasia in man, a coculture of bovine aortic endothelial cells (ECs) and smooth muscle cells (SMCs) was prepared, and the effects of a shear flow on the uptake of lipoproteins by the cells was studied by incubating the EC-SMC coculture as well as an EC monoculture with a culture medium containing either DiI-LDL or DiI-Ac-LDL and subjecting to a laminar shear flow. It was found that in both the presence and absence of a shear flow that imposed the ECs an area mean shear stress of 13.3 dynes/cm2, the uptake of LDL by an EC-SMC coculture was much greater than that by an EC monoculture, whereas that of Ac-LDL was almost the same. The uptake of LDL by an EC monoculture increased slightly by being exposed to a shear flow, whereas that by an EC-SMC coculture did not. In contrast to this, the uptake of Ac-LDL by both an EC monoculture and an EC-SMC coculture decreased drastically by a shear flow, suggesting that the action of a shear flow on the uptake of Ac-LDL by vascular cells is very different from that of LDL.
Niwa
Koichi
K
Laboratory of Biofluid Dynamics, Research Institute for Electronic Science, Hokkaido University, North 12, West 6, North District, Sapporo 060-0812, Japan. niwa@bfd.es.hokudai.ac.jp
Kado
Tatsunori
T
Sakai
Jiro
J
Karino
Takeshi
T
D000818:Animals; D001011:Aorta; D002417:Cattle; D002478:Cells, Cultured; D018920:Coculture Techniques / Q000379:methods; D004730:Endothelium, Vascular / Q000378:metabolism*; D008077:Lipoproteins, LDL / Q000378:metabolism*; D008856:Microscopy, Fluorescence; D008858:Microscopy, Phase-Contrast; D032389:Myocytes, Smooth Muscle / Q000378:metabolism*; D012212:Rheology; D033081:Shear Strength; D013997:Time Factors
D008077:Lipoproteins, LDL; C032629:acetyl-LDL