Synthesis of Phosphatidyl-dCMP in Human Lymphocytes and Its Enhancement by Chlorpromazine

Abstract
When phytohemagglutinin-stimulated lymphocytes are labeled with [3H]deoxycytidine (dCyd), a compound soluble in organic solvents is formed. Several analytical procedures such as TLC and alkaline hydrolysis of the product obtained after labeling of stimulated lymphocytes with [14C]glycerol and [3H]dCyd suggest that the product synthesized is phosphatidyl-dCMP. This compound is synthesized in much smaller amounts than when permeabilized lymphocytes and [3H] dCTP as a precursor are used. The synthesis of phosphatidyl-dCMP is highly enhanced by chlorpromazine, phosphatidic acid and arachidonic acid; addition of inositol diminishes the amount of detected phosphatidyl-dCMP. This compound may be a precursor of phosphatidylinositol.