PREMATURE MATERNAL MILK--THYROID LINK TO PRETERN INFANT

据我们所知，早产儿的预后正在稳步改善。 他们的新陈代谢需求增加了。这些动物的营养需求 婴儿与足月婴儿是不同的。同样， 内分泌调节是独一无二的，“不成熟”的反馈证明了这一点 甲状腺激素对早产儿促甲状腺激素的调节作用大号 大量数据表明，早产母乳(PMM)对 早产儿，这些母亲的母乳喂养率 戏剧性上升。项目管理的构成及其影响因素分析 因此，新生儿对这些婴儿的成功管理是强制性的。 我们的研究和其他研究证实了足月乳房中TH的存在 牛奶。母乳喂养的足月和早产儿TH水平升高 已经上报了。为了确定PMM的甲状腺成分和 进一步，评估它们对美国人未成熟的甲状腺经济的影响 对于早产儿，我们建议：(1)分离、鉴定和量化：(A) PMM中的T3和T4在第0、2和4周哺乳时使用高效液体 (B)甲状腺激素 PMM中类似物和类甲状腺氨基酸的高效液相色谱联用研究 柱后衍生化，鉴于其潜在的生物活性。(2) ConA-琼脂糖层析法和TSH-RIA法定量检测PMM中TSH水平； 并通过(I)RIA，(II)等电性来表征甲状腺激素结合能力 物理特性的聚焦和电泳法；以及 平衡透析法测定结合性能。(3)确定如何 PMM喂养的早产儿与配方奶喂养的早产儿甲状腺状况不同 通过测定新生儿血清T4、T3、rt3、TSH和总胆红素浓度 孕妇血清和乳汁水平的光。(四)进一步调查 口服促甲状腺激素在未成熟肠道的吸收，检查：(A) 7-15年T3和T4对促甲状腺激素刺激反应的肠道成熟 (B)哺乳大鼠甲状腺的剂量反应；以及 (C)肠道引起的循环生物和/或免疫反应性改变 由Sephadex经口摄入TSH产生的促甲状腺激素 层析、RT-Sh-RIA和腺苷环化酶活力的生物测定。这个 拟议的研究涵盖了新生儿、内分泌学、 生物化学、胃肠病学和生理学。由这些组件生成的数据 调查将使我们更好地了解 早产儿不断变化的激素需求可能会得到满足 由乳汁成分的动态变化所引起的 哺乳。

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.