Fetal Velocimetry & Amino Acid Transport in Pregnancy

胎儿测速

• 批准号: 6750734
• 负责人: FREDERICK C BATTAGLIA
• 金额: $ 34.56万
• 依托单位: UNIVERSITY OF COLORADO DENVER
• 依托单位国家: 美国
• 财政年份: 1997
• 资助国家: 美国
• 起止时间: 1997-09-20 至 2008-01-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6750734
• 关键词: aminoacid transport; blood chemistry; clearance rate; clinical research; galactose; human pregnant subject; human subject; inositol; liver circulation; liver function; mannose; mother /embryo /fetus nutrition; newborn human (0-6 weeks); nutrient bioavailability; nutrition related tag; placental transfer; pregnancy circulation; prenatal growth disorder; stable isotope; ultrasound blood flow measurement; umbilical cord

DESCRIPTION (provided by applicant): The studies outlined are directed at nutrient transport and its relationship to blood flow in pregnancies complicated by intrauterine growth retardation (IUGR). The transport of the 9 essential amino acids across the placenta will be studied using stable isotopes and determining the fetal/maternal enrichments and tracer concentration ratios in normal and IUGR pregnancies. IUGR pregnancies are classified by clinical severity based upon velocimetry findings and FHR data. These data on amino acid transport will be analyzed for the impact of variations in umbilical blood flow directly measured with power Doppler techniques. This will establish whether delivery of amino acids to the fetus in IUGR pregnancies is impacted by a reduction in umbilical blood flow and whether this relationship is nonlinear. The non-glucose carbohydrates including the polyols will be measured in normal and IUGR pregnancies. Specific attention is given to D-mannose and myoinositol which are studied with stable isotopes of each sugar and of D-glucose infused into the maternal circulation till steady state enrichments are established. At that time, the fetal/maternal enrichment ratios for both myoinositol and D-mannose are determined. The glucose carbon incorporation into both mannose and myoinositol will be compared in normal and IUGR pregnancies. The studies will establish which, if any, of these carbohydrates relies upon transplacental transport vs. synthesis within the fetal or placental tissues. It will determine if the transplacental gradient for some carbohydrates and polyols are increased in IUGR pregnancies as the gradient is for glucose. Finally, the impact upon the IUGR newborn of an enormous reduction in hepatic blood flow in utero will be assessed. The newborns with a marked reduction in hepatic blood flow can be detected in utero from the reduction in umbilical blood flow coupled with an increase in the ductus venosus shunt. Evidence of hepatocellular damage will be sought at delivery by analysis of cord blood for specific clotting factors and hepatic enzymes. In addition, functional disturbance in neonatal liver function will be assessed by D-galactose plasmal clearance in the newborn after a milk feeding. These studies will establish important links between blood flow changes in the fetus and nutrient delivery to the fetus.

描述（由申请人提供）：概述的研究针对营养转运及其与宫内生长迟滞（IUGR）复杂性妊娠的血液的关系。将使用稳定的同位素研究9个必需氨基酸在整个胎盘上的运输，并确定正常和IUGR妊娠中胎儿/母体富集和示踪剂浓度比。 IUGR怀孕根据临床严重程度分类，该严重程度基于临床测试结果和FHR数据。这些关于氨基酸转运的数据将分析，以直接用功率多普勒技术测量的脐带血流变化的影响。这将确定在IUGR妊娠中向胎儿递送的氨基酸是否受到脐带血流量的降低以及这种关系是非线性的影响。包括多元醇在内的非葡萄糖碳水化合物将在正常和IUGR妊娠中进行测量。对D-甘露糖和肌醇的D型甘露糖和肌醇的稳定同位素进行了特定的注意，并在建立稳态富集之前，将每种糖的稳定同位素和D-葡萄糖注入孕产妇循环中。当时，确定了肌醇和D-甘露糖的胎儿/母体富集比。将在正常和IUGR妊娠中比较甘露糖和肌醇的葡萄糖碳掺入中。研究将确定这些碳水化合物中的哪种（如果有的话）依赖于胎盘运输与胎儿或胎盘组织中的合成。它将确定某些碳水化合物和多元醇在IUGR妊娠中的移植梯度是否增加，因为该梯度是用于葡萄糖的。最后，将评估对子宫内肝血流的巨大减少对IUGR新生儿的影响。可以在子宫内检测到肝血流显着降低的新生儿，从脐带流动的降低以及导管静脉输液的增加。通过分析特定的凝血因子和肝酶的脐带血分析，将寻求肝细胞损伤的证据。此外，牛奶喂养后，新生儿的D-半乳糖浆清除率将评估新生儿肝功能的功能障碍。这些研究将在胎儿的血流变化与胎儿的营养递送之间建立重要的联系。