[Activity of plasma dopamine-beta-hydroxylase in newborn infants. Implication in prematurity, maternal pathology and growth].

The aim of the study was to determine plasma dopamine-beta-hydroxylase activity (DBH) in newborn infants and possible changes with maturation, mode of delivery and maternal disease: pregnancy-induced hypertension and gestational diabetes. DBH activity was determined by high performance liquid chromatography from 82 neonates divided in 2 groups: group I: 27 neonates (age: 1 to 8 days) including 6 preterm and 21 full-term neonates; group II: 55 full-term neonates divided in 5 classes: A: vaginal delivery; B: forceps; C: elective caesarean section; D: vaginal delivery and maternal hypertension; E: vaginal delivery and gestational diabetes. The plasma DBH activity was low in neonates and not influenced by prematurity. Significantly lower DBH activity was found after caesarean section. Hypertension and gestational diabetes did not affect umbilical cord plasma DBH activity.