VASOACTIVE INTESTINAL PEPTIDE (VIP) IN PRETERM AND TERM NEONATES

Abstract
There is little information on vasoactive intestinal peptide (VIP) in the neonatal period. Plasma concentrations of this biologically important peptide were measured in 159 preterm infants and 98 term neonates. Preterm neonates during the first 4 days of life had plasma VIP concentrations which were 5 times greater than the levels in 12 healthy adult controls (9.6 .+-. 0.7 pmol/l, mean .+-. standard error of the mean, compared with 1.9 .+-. 0.5 pmol/l, P < 0.001), and these elevated concentrations persisted throughout the neonatal period. In contrast term infants on the 6th day of life, had plasma VIP concentrations only half those seen in preterm infants at the same post natal age (P < 0.001). Bottle-fed term infants had higher VIP levels than those who were breast fed (5.6 .+-. 0.4 vs. 4.3 .+-. 0.4, P < 0.05). Plasma VIP concentrations did not change following a feed in any of the groups of neonates studied. The high plasma levels of VIP described may indicate a reduced neuropeptide clearance mechanism in neonates or alternatively, suggest a hitherto unrecognized role for this peptide hormone in the neonatal period.