Modulation by polyamines of the phosphorylation of the channel-forming cytosol protein of bovine brain

It was shown that the protein from the cytoplasm of bovine brain cells, which possesses functional similarity to the protein of membrane potential-dependent sodium channels, is the substrate of cAMP-dependent phosphorylation. Polyamines appreciably inhibit the phosphorylation of cytosolic protein. Spermine proves to be the most active here; in a concentration of 5 mM the inhibition reaches 40%. A possible modulation by polyamines of the functioning of sodium channels in the cell is discussed.