Phosphocholine content of rat sarcoma cells in the presence and absence of serum,

Rat sarcoma cells were grown in vitro in tissue culture medium (DMEM) supplemented with 10% foetal calf serum for 5 to 8 days followed by serum withdrawal to produce populations of cells with a variety of cell cycle distributions. Phosphocholine (PCho) and choline content and S + G2 fraction were determined. The phosphocholine content of faster growing populations of serum supplemented cells was higher than the slower growing populations. Choline content was not consistently associated with S + G2 fraction. Serum deprivation was accompanied by a decrease in S + G2 fraction after 24 hours but even after 48 hours PCho content was only slightly decreased.