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 microM H-89 for 1 h decreases the phosphatidylcholine biosynthesis by 50%. This inhibition is prevented by simultaneous addition of 10 microM forskolin, while the choline uptake itself is not affected by H-89.