Plasma prolactin levels in full-term newborn infants with idiopathic edema: response to furosemide.

Abstract

In an attempt to explore the possible role of prolactin (PRL) in the control of neonatal electrolyte homeostasis, this study has been carried out to compare plasma electrolyte concentrations, urine volume and urinary electrolyte excretion as well as plasma PRL levels in healthy full-term neonates with idiopathic edema prior to and after furosemide treatment. No differences in plasma sodium and potassium were demonstrated, edematous neonates, however, had less urine volume and sodium excretion than neonates without edema. Plasma PRL proved to be significantly higher in the edematous group (11.0 +/- 1.9 vs. 4.2 +/- 3.1 U/l, p less than 0.01) but it remained unaltered by furosemide challenge (8.5 +/- 1.5 U/l) in spite of the marked elevation of urine flow and sodium excretion. It is concluded that PRL may be involved in the control of the volume and composition of the body fluids in the neonate but further studies are needed to define the effect of changes in body composition on the neonatal PRL secretion.