Lipid transfer between endothelial and smooth muscle cells in coculture

Abstract

A coculture system was employed to study the interactions between endothelium and vascular smooth muscle cells in arachidonic acid metabolism. Bovine aortic endothelial cells grown on micropore filters impregnated with gelatin and coated with fibronectin are mounted on polystyrene chambers and suspended over confluent smooth muscle cultures. The endothelial basal laminae are oriented toward the underlying smooth muscle, and the two layers are separated by only 1 mm. Each cell layer was assayed individually: apical and basolateral fluid also was collected separately for assay. Fatty acids, including arachidonic acid, are readily transferred between the endothelial and smooth muscle cells in this system. Distribution of the incorporated fatty acids among the lipids of each cell is the same as when the fatty acid is added directly to the culture medium. Arachidonic acid released from endothelial cells is available as a substrate for prostaglandin production by smooth muscle. In addition, fatty acids released from the smooth muscle cells can pass through the endothelium and accumulate in the fluid bathing the endothelial apical surface. These fatty acid interchanges may be involved in cell-cell signaling within the vascular wall, the clearance of lipids from the vascular wall, or the redistribution of arachidonic acid and other polyunsaturated fatty acids between adjacent cell types. Furthermore, the findings suggest that prostaglandin production by smooth muscle cells can occur in response to stimuli that cause arachidonic acid release from endothelial cells.

Transport of lipoprotein lipase across endothelial cells.

“…This did not change the transport of '25I-LPL into the medium, compared to the filters on which the usual number of cells was seeded, demonstrating that increasing the number of cells seeded did not increase the barrier function of the monolayer. Transport rates of [14C]albumin from the basal to the apical side of the monolayers were <1.5% per hr, a rate similar to that reported by Stoll and Spector (15). At the conclusion of each LPL transport experiment, the monolayers were stained with 2% toluidene blue to verify the uniformity of the monolayer.…”

1-O-alkyl-2-acetyl-sn-glycerol: a platelet-activating factor metabolite with biological activity in vascular smooth muscle cells.

“…Porcine pulmonary artery smooth muscle cells which had previously been characterized as a well differentiated smooth muscle cell line (Stoll and Spector, 1987) were grown in Dulbecco's Minimal Essential Medium (GIBCO, Grand Island, NY) supplemented with 10% fetal bovine serum (HyClone, Logan, UT), MEM Nonessential Amino Acids (GIBCO), MEM Vitamin Solution (GIBCO), 2 mM L-glutamine (Sigma), 15 mM 4-(2-hydroxyethyl)-1 -piperazineethane sulfonic acid (Sigma, St.…”

Effect of reduced levels of the LDL receptor of Ehrlich ascites tumor cells on cholesterol uptake and cell proliferation: A coculture study with baby hamster kidney cells

“…One of the most frequently used coculture system so far is the one employing endothelial and smooth muscle cells. This system has revealed that, e.g., arachidonic acid released from endothelial cells is available as substrate for prostaglandin production by smooth muscle cells (Stoll and Spector, 1987, 1989, 1993Jaworski et al, 2001). These fatty acid interchanges may be involved in cellecell signaling within the vascular wall.…”