PROSTAGLANDINS AND ESSENTIAL FATTY ACID IN PRETERM AND TERM MILKS AT DIFFERENT STAGES OF LACTATION

Abstract

It is thought that prostaglandins(PGs) in human milk may play a role in modulating the gastrointestinal physiology of breast-fed infants. In this study, we measured PGs levels by radioimmunoassay and essential fatty acid(EFA) by gaschromatography in aliquots of foremilk and hindmilk obtained at different stages of lactation (colostrum:1-3 days, transitional milk:6-9 days, mature milk: 1 month) from 6 preterm mothers(26-34 weeks: preterm milk) and 7 term mothers(39-41 weeks: term milk). Results (1) Human milk levels of PGE2 and PGF2α were approximately 1.5-2 times higher than plasm levels, but PGE1 levels in human milk were similar to those of plasma. (2) No difference of PGs levels could be found between foremilk and hindmilk. (3) PGs levels in preterm milk were not different from those of term milk at each stages of lactation. (4) Preterm milk levels of linoleic acid were significantly lower than term milk levels (p<0.05) in colostrum, and significantly higher (p<0.01) in mature milk. (5) Arachidonic acid in preterm milk were similar to those of term milk, but the levels decreased with advancing of lactation in both types of milk. (6) PGs levels did not correlate with EFA levels both in preterm and term milks. Maintaining stable levels of PGs in human milk, irrespective of lactation, found in this study may suggest the important physiological roles of the gastrointestinal truct.