RESUMO
AIM: To determine EGF contents in human milk, frech cow's milk and cow's milk-based infant formulas and the relationship between EGF content of human milk and neonatal maturity.METHODS: EGF contents in 57 human colostrum from mothers delivering prematurely and at term, 4 different fresh cow's milk and 8 different cow's-milk-based infant formulas with hydrolyzed and non-hydrolyzed proteins were determined by radioimmunoassay (RIA). RESULTS: Human milk from mothers of premature infants had higher EGF content compared to that from mothers of term infants[(28.2?10.3) nmol/L vs(17.3?9.6) nmol/L]. There was a negative correlation between EGF content of human milk and gestational age, birth weight of neonates. The values in fresh cow's milk [(16.6?3.8) nmol/L]were similar to that in human term milk. The contents in non-hydrolyzed protein formulas[(7.5?1.9) nmol/L]were much lower than that in human milk and fresh cow's milk. No immunoreactive EGF was detected in all hydrolyzed protein formulas. CONCLUSION: The occurrence of high EGF concentration in premature milk may represent a maternal compensatory mechanism to accelerate the growth and maturation in immature infants. Lack of EGF in formulas suggests that they may not suitable for those newborns with immature or damaged gastrointestinal tract.