Lipid Metabolism of Primary Cultures of Aortic Smooth Muscle Cells

Abstract

<p>Smooth muscle cells from pig aortic media were grown in tissue culture, in medium containing 10% calf serum. Lipid biosynthesis from radioactive substrates 1-¹⁴C-acetate, U-¹⁴C-D-glucose, 1-¹⁴C-oleic acid and ³²P-phosphoric acid was measured. In addition, the influence of various sera, including pig serum, normolipemic human serum (NLHS), and hyperlipemic human serum (HLHS) on lipid biosynthesis from acetate and phosphoric acid was studied</p> <p>Compared to calf serum, all three test sera caused a stimulation of lipid synthesis in the lipid classes, phospholipid (PL), free fatty acids (FFA), triglycerides (TG) and cholesterol esters (CE), and an inhibition of cholesterol plus diglyceride (S + DG) synthesis. The extent of stimulation was least for pig serum and greatest for HLHS; the inhibition of S + DG was greatest for HLHS and least for pig serum. It was noted that the HLHS stimulation of CE synthesis was proportionately greater than the stimulation of the other lipid classes and that the HLHS inhibition of S + DG was significantly greater than that seen with the other test sera.</p> <p>The morphology of cultured aortic smooth muscle cells grown in 10% calf serum and 10% HLHS was examined by means of scanning and transmission electronmicroscopy. It was observed that HLHS caused degenerative alterations in the morphology of the cultured smooth muscle cells, such as an abundance of lipid droplets and cellular debris. The implications of these results in relation to the development of atherosclerosis are discussed.</p>