ADAPTIVE REGULATION OF NUTRIENT TRANSPORT OF THE GUT

该项目位于营养学和胃肠病学之间的界面。 它询问肠道的营养吸收机制是如何适应性地 监管. 目标集中在三个问题上。 1.在我们的大脑中 营养吸收的变化与饮食的变化，怀孕，和其他正常 和疾病相关的症状吗 2.负责的机制是什么 这些变化？ 3.这些变化的信号是什么？ 具体目标有四个方面： 1.什么样的饮食条件能最大限度地诱导四种主要的 钠离子依赖性氨基酸转运蛋白？ 这项研究将指导尝试， 分离转运蛋白并理解诱导信号。 2.转运蛋白的底物依赖性诱导是否仅发生在 分化的隐窝细胞，还是成熟的肠上皮细胞？ 3.有什么样的模式，触发信号，功能意义， 机制，并可能作为消化瓶颈的作用， 个体发育过程中的转运蛋白 4.实验性糖尿病通过什么机制改变营养吸收 在肠旁吗 使用的主要方法是测量示踪剂摄取，肠形态测量， 和转运站编号 该项目对健康有以下影响：1。的饮食作用 氨基酸，不仅作为必需营养素，而且作为 其他营养素的吸收; 2.改变血浆的健康后果 由于肠道营养摄取改变而导致的营养水平; 3.改变 糖尿病和其他疾病状态中的营养摄取。

This project lies at the interface between nutrition and gastroenterology. It asks how the nutrient uptake mechanisms of the intestine are adaptively regulated. The objectives focus on three questions. 1. What are the patterns of changes in nutrient uptake with diet changes, pregnancy, and other normal and disease-related conditions? 2. What are the mechanisms responsible for these changes? 3. What are the signals for these changes? The specific aims are four-fold: 1. What dietary conditions yield maximal induction of each of the four main Na+-dependent amino acid transporters? This study will guide attempts to isolate transporters and to understand inducing signals. 2. Does substrate-dependent induction of transporters take place only in differentiating crypt cells, or in mature enterocytes as well? 3. What are the patterns, triggering signals, functional significance, mechanisms, and possible role as digestive bottlenecks, for the changes in transporters during ontogenetic development? 4. By what mechanisms does experimental diabetes alter nutrient absorption by the intestine? The main methods to be used measure tracer uptake, intestinal morphometry, and transporter site number. The project has health-related implications for: 1. the dietary role of amino acids, not only as essential nutrients but also as inducers of absorption of other nutrients; 2. health consequences of altered plasma levels of nutrients due to altered intestinal nutrient uptake; 3. altered nutrient uptake in diabetes and other disease states.