PREMATURE MATERNAL MILK--THYROID LINK TO PRETERN INFANT

早产母乳——甲状腺与早产儿的关系

• 批准号: 3320000
• 负责人: LINDA V OBERKOTTER
• 金额: $ 6.58万
• 依托单位: FLORIDA INSTITUTE OF TECHNOLOGY
• 依托单位国家: 美国
• 财政年份: 1985
• 资助国家: 美国
• 起止时间: 1985-09-01 至 1988-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3320000
• 关键词: blood chemistry; child physical development; developmental nutrition; dietary supplements; electrofocusing; gastrointestinal absorption /transport; gel filtration chromatography; gestational age; high performance liquid chromatography; hormone analog; hormone regulation /control mechanism; human milk; human subject; iodine; lactation; newborn animals; nutrition related tag; premature infant human; radioimmunoassay; respiratory distress syndrome of newborn; thyroid hormones; thyrotropin

The prognosis for premature infants has steadily improved as our knowledge of their metabolic requirements increases. The nutritional needs of these infants are distinct from those of their full-term counterparts. Likewise, endocrine regulation is unique, as evidenced by "immature" feedback regulation of TSH by thyroid hormone (TH) in preterm neonates. A large body of data indicate the advantages of premature maternal milk (PMM) for the preterm infant, and the rate of breast feeding among these mothers has risen dramatically. Analysis of the composition of PMM and how it affects the neonate is thus mandatory to successful management of these infants. Our studies and others have confirmed the presence of TH in term breast milk. Elevated TH levels in breast-fed full- and pre-term infants have been reported. In order to define the thyroidal components of PMM and further, evaluate their influence upon the immature thyroid economy of the preterm infant, we propose to: (1) Isolate, identify, and quantify: (a) T3 and T4 in PMM at 0, 2, and 4 wks lactation using high performance liquid chromatography (HPLC) and radioimmunoassay (RIA); and (b) thyroid hormone analogues and thyromimetic amino acids in PMM by HPLC coupled with post-column derivatization, in light of their potential bioactivity. (2) Quantify levels of TSH in PMM by ConA-Sepharose chromatography and TSH-RIA; and characterize thyroxine-binding capacity by (i) RIA, (ii) isoelectric focusing and electrophoresis for physical characterization; and (iii) equilibrium dialysis to determine binding properties. (3) Determine how thyroid status of PMM-fed infants differs from that of formula-fed preterm neonates, by assessing serum T4, T3, rT3, TSH, and TBG concentrations in light of maternal serum and milk levels. (4) Investigate further absorption by the immature gut of peroral TSH, examining: (a) effect of gut maturation upon T3 and T4 responses to thyrotropin stimulation in 7-15 day old rat pups; (b) dose-responsiveness of the suckling rat thyroid; and (c) gut-induced alterations of bio- and/or immuno-reactivity of circulating thyrotropin resulting from peroral ingestion of TSH, by Sephadex chromatography, rTSH-RIA, and bioassay of adenylate cyclase activity. The proposed studies encompass the fields of neonatology, endocrinology, biochemistry, gastroenterology and physiology. The data generated by these investigations will lead to a greater understanding of the extent to which the changing hormonal requirements of the preterm infant may be satisfied by the dynamic changes in breast milk composition during the course of lactation.

据我们所知， 他们的代谢需求增加。 这些人的营养需求 婴儿与足月婴儿不同。 同样地， 内分泌调节是独特的，如“不成熟”反馈所证明的 早产儿甲状腺激素（TH）对TSH的调节。 大 大量的数据表明早产母乳（PMM）的优势， 早产儿和这些母亲的母乳喂养率 急剧上升。 分析PMM的构成及其影响 因此，新生儿是成功管理这些婴儿的必需品。 我们的研究和其他研究已经证实了足月乳腺中存在TH 牛奶 母乳喂养的足月儿和早产儿TH水平升高， 被举报。 为了确定PMM的甲状腺成分， 此外，评估它们对未成熟甲状腺经济的影响。 早产儿，我们建议：（1）分离，识别和量化：（a） 泌乳0、2和4周时PMM中的T3和T4（使用高效液体） 色谱法（HPLC）和放射免疫测定法（RIA）;和（B）甲状腺激素 PMM中类似物和拟甲状腺氨基酸的HPLC法， 柱后衍生，鉴于其潜在的生物活性。 （二） 用ConA-Sepharose层析法和TSH-RIA法测定PMM中TSH的含量; 并通过（i）RIA，（ii）等电 用于物理表征的聚焦和电泳;以及（iii） 平衡透析以确定结合性质。 (3)确定如何 PMM喂养婴儿的甲状腺状态与配方奶粉喂养的早产儿不同 新生儿，通过评估血清T4，T3，rT 3，TSH和TBG浓度， 根据母体血清和乳汁水平。 (4)进一步调查 未成熟肠道对口服TSH的吸收，检查：（a） 在7-15岁时，T3和T4对促甲状腺激素刺激的反应后， （B）乳鼠甲状腺的剂量反应性;和 (c)肠道诱导的循环系统生物和/或免疫反应性的改变 经口摄入促甲状腺激素，葡聚糖凝胶法 层析、rTSH RIA和腺苷酸环化酶活性的生物测定。 的 建议的研究包括泌尿学，内分泌学， 生物化学、胃肠病学和生理学。 由这些产生的数据 调查将导致更好地了解在多大程度上， 可以满足早产儿不断变化的激素需求 母乳成分的动态变化， 哺乳期