Phosphocholine and choline content of rat sarcoma cells grown 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.