Speziale M V, Mannino F L, Hastings R H, Deftos L J
Department of Pediatrics, University of California, San Diego, La Jolla 92093, USA.
Pediatr Res. 1998 May;43(5):660-5. doi: 10.1203/00006450-199805000-00015.
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.
甲状旁腺激素相关蛋白（PTHrP）及其受体存在于多种正常哺乳动物胚胎组织中，在这些组织中它显然调节细胞的生长和分化。PTHrP可刺激大鼠胎儿肺组织外植体中的磷脂酰胆碱合成，提示其在胎儿Ⅱ型肺泡成熟和表面活性剂产生中发挥作用。我们研究了新生儿气管吸出物中的PTHrP水平。我们在出生后24小时内收集了40例插管新生儿的气管吸出物。使用针对PTHrP肽38 - 64的兔抗血清通过放射免疫分析法测定PTHrP水平。我们发现，孕周小于35周（p = 0.02）且出生体重小于2kg（p = 0.04）的婴儿气管吸出物中的PTHrP水平显著较低。我们还发现，男性早产儿（孕周<35周）的气管吸出物中PTHrP水平显著低于女性婴儿（p = 0.01），且在需要多次使用表面活性剂的早产儿中也是如此（p = 0.005）。产前接受类固醇治疗的早产儿气管吸出物中的PTHrP水平显著较高（p = 0.02）。PTHrP与肺成熟的各种指标相关，可能被证明是分化和生长的介质。
