A SELECTIVE INHIBITOR OF CYCLIC AMP-DEPENDENT PROTEIN-KINASE, N-[2-BROMOCINNAMYL(AMINO)ETHYL]-5-ISOQUINOLINESULFONAMIDE (H-89), INHIBITS PHOSPHATIDYLCHOLINE BIOSYNTHESIS IN HELA-CELLS

In this study, we report that the potent and selective inhibitor of cyclic AMP-dependent protein kinase, N-[2-bromocinnamyl(amino)ethyl]-5-isoquinolinesulfonamide (H-89) interferes with the incorporation of choline into phosphatidylcholine in HeLa cells. Treatment of cells with 10-mu-M H-89 for 1 h decreases the phosphatidylcholine biosynthesis by 50%. This inhibition is prevented by simultaneous addition of 10-mu-M forskolin, while the choline uptake itself is not affected by H-89.