[Content of ceruloplasmin as a source of copper in breast milk at different stages of lactation].

The concentration of ceruloplasmin decreased about 10 times during the first 20 days of lactation, judging from both immunoelectrophoretic quantitation and oxidase activity measurements. On the other hand, the daily copper consumption per 1 kg of newborn body weight remains constant (about 10 micrograms per day). The artificial fed children receive many folds excesses of the copper ions. The mechanisms, controlling the consumption of copper by newborns via the modulation of ceruloplasmin gene expression in the cells of the lactating mammary gland in the mother are discussed.