THE DECREASED TRANSFER OF ARACHIDONIC-ACID FROM TRIGLYCERIDES TO PHOSPHOLIPIDS DURING PROLIFERATION OF A HUMAN GASTRIC TUMOR (HGT) CELL-LINE IS NOT LINKED TO MODIFICATION OF MEMBRANE FLUIDITY

Prelabeling-chase experiments with [C-14]arachidonic acid in human can cer gastric cells (HGT) indicated a preferential incorporation of arac hidonic acid into triglycerides followed by a transfer to phospholipid s. This phenomenon was quicker using cells in log phase growth than in quiescent phase and was not linked to modification of HGT membrane fl uidity assessed by the fluorescence polarization of the 1,6-diphenyl h exatriene probe. By contrast, growing cells in a medium enriched with oleic or linoleic acids increase plasma membrane fluidity. The importa nce of the site of arachidonic incorporation in HGT lipid is discussed .