Parker C R, Fortunato S J, Carr B R, Owen J, Hankins G D, Hauth J C
Department of Obstetrics and Gynecology, University of Alabama, Birmingham 35294.
Pediatr Res. 1988 Apr;23(4):348-51. doi: 10.1203/00006450-198804000-00002.
Apolipoprotein A-1 (Apo A-1) is the major protein constituent of high-density lipoprotein (HDL) and Apo A-1 plays an important role in lipid metabolism and may be protective against atherosclerosis in adults. However, little is known about HDL and Apo A-1 in the developing human fetus. Herein we investigated the relationship of Apo A-1 levels in umbilical cord blood at delivery to gestational age and HDL cholesterol. Fetal plasma levels of Apo A-1, which were not correlated with those in maternal plasma, were significantly lower among newborns delivered at 21-26 wk gestation (52 +/- 4.4 mg/dl, mean +/- SE) than in those delivered at 33-34 wk gestation (87 +/- 5.8 mg/dl). Thereafter, the mean umbilical cord plasma levels of Apo A-1 remained relatively constant (101 mg/dl at 39-40 wk of gestation). We found no significant correlations between Apo A-1 levels and fetal sex, race, or delivery method. At equivalent gestational ages and birth weights, however, Apo A-1 levels in white newborns tended to be lower than those in black infants. The Apo A-1/HDL cholesterol ratio in umbilical cord blood rose progressively from 2.5 (27-28 wk gestation) to 3.8 at term, due largely to increased Apo A-1 levels but little change in the mean HDL cholesterol levels, which ranged from 22-24 mg/dl at each gestational period. These results are suggestive that fetal plasma Apo A-1 is derived solely from fetal sources and that the rate of production and/or clearance of Apo A-1 is altered during the latter third of human intrauterine development.
载脂蛋白A-1（Apo A-1）是高密度脂蛋白（HDL）的主要蛋白质成分，Apo A-1在脂质代谢中起重要作用，对成年人的动脉粥样硬化可能具有保护作用。然而，关于发育中的人类胎儿的HDL和Apo A-1，人们知之甚少。在此，我们研究了分娩时脐带血中Apo A-1水平与胎龄和HDL胆固醇之间的关系。胎儿血浆中Apo A-1水平与母体血浆中的水平无关，妊娠21 - 26周分娩的新生儿（52±4.4mg/dl，均值±标准误）的Apo A-1水平显著低于妊娠33 - 34周分娩的新生儿（87±5.8mg/dl）。此后，脐带血浆中Apo A-1的平均水平保持相对稳定（妊娠39 - 40周时为101mg/dl）。我们发现Apo A-1水平与胎儿性别、种族或分娩方式之间无显著相关性。然而，在相同的胎龄和出生体重下，白人新生儿的Apo A-1水平往往低于黑人婴儿。脐带血中Apo A-1/HDL胆固醇比值从妊娠27 - 28周时的2.5逐渐升至足月时的3.8，这主要是由于Apo A-1水平升高，而平均HDL胆固醇水平变化不大，每个妊娠期的HDL胆固醇水平在22 - 24mg/dl之间。这些结果提示胎儿血浆中的Apo A-1仅来源于胎儿，并且在人类子宫内发育的后三分之一阶段，Apo A-1的产生和/或清除速率发生了改变。
