The incorporation of the phosphate esters of N-substituted aminoethanols into the phospholipids of brain and liver.

1. The phosphate esters of dimethylaminoethanol and monomethylaminoethanol can be incorporated from their cytidine diphosphate esters into the phospholipids of brain and liver dispersions; the deoxycytidine nucleotides of the same bases are less effective precursors. 2. The cytidylyltransferases of brain and liver are less effective in forming the cytidine diphosphate esters of monomethylaminoethanol and dimethylaminoethanol than those of ethanolamine and choline.