Lipid metabolism of Ehrlich ascites tumor cells grown in chemically defined albumin medium.

Total lipids of Ehrlich ascites tumor cells grown in nutrient medium supplemented with 1% bovine serum albumin instead of 15% native horse serum and rate of incorporation of [3H] acetate into total lipids are reduced, while the cholesterol content of the cells is higher than of controls grown in normal medium. The lower lipid content of cells cultured in albumin supplemented medium is explained by a lack of exogenous lipids, which are normally taken up from the serum containing nutrient medium. A several fold increase of incorporation of labelled choline and ethanolamine into the phospholipids of the cells grown in the modified medium is observed. We suggest, that the observed stimulation of the incorporation of phospholipid precursors reflects changes in the dynamic state of the membranes produced by serum depletion.