scholarly journals Specific high-affinity binding of high density lipoproteins to cultured human skin fibroblasts and arterial smooth muscle cells.

1983 ◽  
Vol 71 (3) ◽  
pp. 525-539 ◽  
Author(s):  
R Biesbroeck ◽  
J F Oram ◽  
J J Albers ◽  
E L Bierman
Keyword(s):  
Smooth Muscle ◽  
Smooth Muscle Cells ◽  
Human Skin ◽  
Muscle Cells ◽  
High Density Lipoproteins ◽  
Affinity Binding ◽  
Human Skin Fibroblasts ◽  
High Affinity Binding ◽  
High Affinity ◽  
Arterial Smooth Muscle Cells

scholarly journals Movement of plasma-membrane sterols to the endoplasmic reticulum in cultured cells

1987 ◽  
Vol 248 (1) ◽  
pp. 237-242 ◽  
Author(s):  
J P Slotte ◽  
E L Bierman
Keyword(s):  
Endoplasmic Reticulum ◽  
Smooth Muscle ◽  
Plasma Membrane ◽  
Smooth Muscle Cells ◽  
Human Skin ◽  
Cultured Cells ◽  
Muscle Cells ◽  
Skin Fibroblasts ◽  
Human Skin Fibroblasts ◽  
Arterial Smooth Muscle Cells

The spontaneous turnover of plasma-membrane sterols, as measured by their transfer to the endoplasmic reticulum, was measured in quiescent cultured human skin fibroblasts and monkey arterial smooth-muscle cells. The plasma-membrane sterol pool was pulse-labelled with trace amounts of either [3H]desmosterol or [3H]cholesterol. We then measured the enzymic conversion of [3H]desmosterol into [3H]cholesterol and of [3H]cholesterol into [3H]cholesteryl esters in intact cells. Depending on the probe used, markedly different transfer or conversion rates were found in these cells. In quiescent human skin fibroblasts, incubated in a serum-free medium, about 1.1% of the plasma-membrane [3H]desmosterol was converted into [3H]cholesterol/h, whereas in monkey arterial smooth-muscle cells the corresponding rate was 0.4%. Under similar experimental conditions, these cells esterified less than 0.02% (fibroblasts) and 0.12% (smooth-muscle cells) of the plasma-membrane [3H]cholesterol/h. The movement of sterols from the plasma membrane to the endoplasmic reticulum, as measured by the conversion of [3H]desmosterol into [3H]cholesterol was not blocked by colchicine, but was markedly enhanced by 3% (w/v) dimethyl sulphoxide. In all, these results indicate that plasma-membrane sterols of cultured cells are continuously transferred to the interior of the cell at a rate substantially higher than previously appreciated. This turnover of plasma-membrane sterol molecules took place even when there was no mass transfer of sterols into the cells.

scholarly journals Histidine-rich glycoprotein inhibits the antiproliferative effect of heparin on smooth muscle cells.

1987 ◽  
Vol 165 (3) ◽  
pp. 908-913 ◽  
Author(s):  
D P Hajjar ◽  
D B Boyd ◽  
P C Harpel ◽  
R L Nachman
Keyword(s):  
Cell Proliferation ◽  
Smooth Muscle ◽  
Endothelial Cell ◽  
Inflammatory Response ◽  
Smooth Muscle Cells ◽  
Anticoagulant Activity ◽  
Muscle Cells ◽  
Antiproliferative Effect ◽  
High Affinity ◽  
Arterial Smooth Muscle Cells

Histidine-rich glycoprotein (HRGP), an alpha-glycoprotein in human plasma that is also present in platelets and macrophages, binds heparin with high affinity and neutralizes its anticoagulant activity. We now report that HRGP specifically inhibits the antiproliferative effect of heparin on arterial smooth muscle cells while other heparinoid-binding proteins do not influence mitogenesis. The multicellular inflammatory response to endothelial injury characterized, in part, by the influx of platelets and macrophages, may be associated with HRGP release into the arterial microenvironment. This release of HRGP may allow smooth muscle cell proliferation and atherogenesis by inhibiting the action of endothelial cell-derived heparinoid substances.

Sign in / Sign up

Export Citation Format

Share Document