The
polyamine concentration in rat milk and food, human milk, and infant formulas was estimated by HPLC. In rat milk, the concentration of
putrescine and
spermine was low (generally under 2.5 nmol.mL-1 for
putrescine and under 1 nmol.mL-1 for
spermine). The
spermidine concentration was higher and seemed to increase during lactation. The rat food was richer in
polyamines than the rat milk (about 150 times for
putrescine and
spermine, about 30 times for
spermidine). We already proved that ingestion of
spermine or
spermidine can induce precocious maturation of the rat intestine. The present observations suggest that
polyamines contained in rat food could play an important role in postnatal maturation of the rat intestine. The
polyamine concentration of human milk was measured from 60 different mothers during a period extending from the 1st wk to the 6th mo of lactation. Great variation was observed. During the 1st mo of lactation, the general pattern was as follows:
putrescine concentration generally varied little (from 1 to 3 nmol.mL-1),
spermine and
spermidine concentrations showed a similar pattern (the highest values appeared at the end of the 1st wk of suckling). After the 4th mo of lactation,
putrescine concentration increased slightly, whereas
spermine and
spermidine concentration stayed almost stable. The concentrations of
polyamines in 18 powdered milks for babies were estimated.
Spermine and
spermidine contents were lower than those in human milk. A protective effect of
spermine or
spermidine against alimentary
allergies is suggested.