Hanna C E, Keith L D, Colasurdo M A, Buffkin D C, Laird M R, Mandel S H, Cook D M, LaFranchi S H, Reynolds J W
Department of Pediatrics, Oregon Health Sciences University, Portland 97201.
J Clin Endocrinol Metab. 1993 Feb;76(2):384-7. doi: 10.1210/jcem.76.2.8381799.
Extremely premature infants manifest clinical features suggestive of adrenal insufficiency. Yet, serum cortisol levels are similar in ill and well preterm infants in a setting where one would expect high stress levels in the ill infants. We investigated the hypothalamic-pituitary-adrenal axis in 17 extremely low birth weight stressed premature infants, mean birth weight 739 g, gestational age, 26.1 weeks, using ovine CRH (oCRH) and ACTH stimulation. oCRH (1 microgram/kg) was administered at 2-7 days of life (mean = 4.1). ACTH rose from a basal value 6.0 +/- 0.8 pmol/L (mean +/- SEM) to 9.6 +/- 1.8 pmol/L (P < 0.01) at 15 min and 9.5 +/- 1.7 pmol/L (P < 0.01) at 60 min. Basal cortisol rose from 349.3 +/- 58.1 nmol/L to 422.3 +/- 57.9 nmol/L (P < 0.01) at 15 min and 568.7 +/- 60.2 nmol/L (P < 0.01) at 60 min. Cortisol values remained significantly (P < 0.05) elevated 24 h after oCRH. An ACTH stimulation test performed 24 h after the oCRH test demonstrated a significant cortisol rise from 603.5 +/- 130.5 nmol/L to 882.7 +/- 136.6 nmol/L (P < 0.05) at 60 min. Plasma CRH immunoactivity was also measured before oCRH testing and was detectable in 10 of 15 infants. The mean CRH immunoactivity was 21.8 +/- 4.4 pmol/L in the infants, significantly higher than 8 adult male controls (P < 0.04). Our results show a normal pituitary response to ovine CRH and a normal adrenal response to ACTH. We hypothesize that cortisol levels are inappropriately low in some ill preterm infants because of the inability of the extremely premature brain to recognize the stress of the illness or because of inadequate hypothalamic secretion of CRH. The significance of the measurable plasma CRH in the first week of life is unknown.
极早早产儿表现出提示肾上腺功能不全的临床特征。然而，在预期患病婴儿应激水平较高的情况下，患病和健康早产儿的血清皮质醇水平相似。我们使用羊促肾上腺皮质激素释放激素（oCRH）和促肾上腺皮质激素（ACTH）刺激试验，对17例出生体重极低且处于应激状态的早产儿进行了下丘脑-垂体-肾上腺轴的研究，这些早产儿平均出生体重739克，胎龄26.1周。在出生后2 - 7天（平均4.1天）给予oCRH（1微克/千克）。ACTH在15分钟时从基础值6.0±0.8皮摩尔/升（平均值±标准误）升至9.6±1.8皮摩尔/升（P<0.01），60分钟时升至9.5±1.7皮摩尔/升（P<0.01）。基础皮质醇在15分钟时从349.3±58.1纳摩尔/升升至422.3±57.9纳摩尔/升（P<0.01），60分钟时升至568.7±60.2纳摩尔/升（P<0.01）。oCRH后24小时皮质醇值仍显著升高（P<0.05）。在oCRH试验24小时后进行的ACTH刺激试验显示，60分钟时皮质醇从603.5±130.5纳摩尔/升显著升至882.7±136.6纳摩尔/升（P<0.05）。在oCRH试验前还测量了血浆CRH免疫活性，15例婴儿中有10例可检测到。婴儿的平均CRH免疫活性为21.8±4.4皮摩尔/升，显著高于8名成年男性对照（P<0.04）。我们的结果显示垂体对羊促肾上腺皮质激素释放激素反应正常，肾上腺对促肾上腺皮质激素反应正常。我们推测，一些患病早产儿的皮质醇水平不适当降低，是因为极早早产儿的大脑无法识别疾病的应激，或者是因为下丘脑促肾上腺皮质激素释放激素分泌不足。出生后第一周可测量的血浆CRH的意义尚不清楚。
