Parathyroid hormone-related protein in tracheal aspirates of newborn infants.
PTH-related protein (PTHrP) is found with its receptor in a variety of normal mammalian embryonic tissues where it apparently regulates cellular growth and differentiation. PTHrP stimulates phosphatidylcholine synthesis in rat fetal lung explants, suggesting a role in fetal type II alveolar maturation and surfactant production. We investigated PTHrP levels in tracheal aspirates of newborn infants. We collected tracheal aspirates from 40 intubated newborn infants within the first 24 h of life. PTHrP levels were measured by a RIA using rabbit antisera to PTHrP peptide 38-64. We found significantly lower PTHrP levels in tracheal aspirates from infants born at less than 35 wk of gestation (p = 0.02) and with a birth weight less than 2 kg (p = 0.04). We also found significantly lower PTHrP levels in male preterm (<35 wk of gestation) infants compared with female infants (p = 0.01), and in preterm infants who required multiple doses of surfactant (p = 0.005). Preterm infants exposed to antenatal steroids had significantly higher levels of PTHrP in tracheal aspirates (p = 0.02). PTHrP is associated with various indices of lung maturation and may prove to be a mediator of differentiation and growth.
Speziale
M V
MV
Department of Pediatrics, University of California, San Diego, La Jolla 92093, USA.
Mannino
F L
FL
Hastings
R H
RH
Deftos
L J
LJ
D000818:Animals; D005260:Female; D005865:Gestational Age; D006801:Humans; D007106:Immune Sera; D007231:Infant, Newborn / Q000502:physiology*; D007234:Infant, Premature / Q000502:physiology*; D001239:Inhalation; D008168:Lung / Q000502:physiology / Q000503:physiopathology; D008297:Male; D044162:Parathyroid Hormone-Related Protein; D011247:Pregnancy; D011297:Prenatal Exposure Delayed Effects; D011506:Proteins / Q000032:analysis*; D011817:Rabbits; D051381:Rats; D012127:Respiratory Distress Syndrome, Newborn / Q000503:physiopathology*; D012727:Sex Characteristics; D013256:Steroids / Q000627:therapeutic use; D014132:Trachea
D007106:Immune Sera; C470121:PTHLH protein, human; D044162:Parathyroid Hormone-Related Protein; D011506:Proteins; D013256:Steroids