PRODUCTION AND ABSORPTION OF INTESTINAL GAS

肠道气体的产生和吸收

• 批准号: 3225016
• 负责人: MICHAEL D LEVITT
• 金额: $ 7.13万
• 依托单位: UNIVERSITY OF MINNESOTA
• 依托单位国家: 美国
• 财政年份: 1979
• 资助国家: 美国
• 起止时间: 1979-01-01 至 1996-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3225016
• 关键词: carbon monoxide; dietary fiber; dogs; enteric bacteria; erythrocytes; fructose; gastrointestinal absorption /transport; gastrointestinal disorder; gastrointestinal gas; gastrointestinal motility /pressure; human subject; hydrogen; intestinal mucosa; intestinal villi; laboratory rat; lactose; lung disorder; malabsorption; nutrition related tag; oxidative stress; respiratory gas level

The overall goal of this proposal is to continue my studies that have employed gases as probes to study human physiology. The specific aims of this proposal are as follows. 1) Quantitate the efficiency of luminal stirring in the normal human small intestine via measurements of the hydrolysis of disaccharides. this stirring determines the thickness of the unstirred layer that covers the mucosa and provides a diffusion barrier to the absorption of all solutes. In addition, the influence of the viscosity and nutrients of luminal contents on luminal stirring will be investigated. As a related project, the efficiency of stirring of the intervillous space of dogs and rats will be studied to assess the role of villous surface area on absorption and surface hydrolysis. Data from these studies can be compared to that from subjects with intestinal disease to determine if inadequate luminal stirring plays a role in the malabsorption of patients with bowel disease. 2) Separately identify the role of H2 producing the H2 consuming organisms: a) in subjects with very high or very low H2 production and b) in subjects adapting to a high fiber diet or lactase deficient subjects adapting to a high lactose diet. H2 is a major component of flatus and hence understanding of the factors regulating H2 accumulation in the gut is important to understanding the pathogenesis and potential approaches to therapy of flatulence. Subjects ingesting high dose of fiber or lactose initially have severe flatulent symptoms that improve with continued ingestion of the foodstuff. This improvement seemingly reflects an adaptation of the gas producing flora and these studies will determine if changes in H2 producing or H2 consuming organisms are involved in this adaptation. 3) Utilize measurements of carbon monoxide (CO) in alveolar air to assess red blood cell (RBC) turnover. At present there is no simple, rapid test for RBC turnover and it is proposed that the assessment of alveolar PCO corrected for environmental PCO will provide a clinically useful test for RBC survival. 4) Utilize measurements of CO release from substrates as a measure of oxidant injury. The proposed studies will use fructose as a test compound to: a) identify the carbons involved in this oxidation and b) test the oxidant-antioxidant activity of various biological fluids. Oxidant injury has widespread implications for health, and CO release appears to be a unique marker of this injury.

该提案的总体目标是继续我的研究 使用气体作为探针来研究人体生理学。 具体目标 本提案的内容如下。 1) 定量正常人体管腔搅拌的效率 小肠通过测量水解 二糖。 这种搅拌决定了混合物的厚度 覆盖粘膜并提供扩散作用的未搅拌层 阻碍所有溶质的吸收。 此外， 管腔内容物的粘度和营养成分对 将研究管腔搅拌。 作为一个相关项目， 狗和大鼠绒毛间隙的搅拌效率 将进行研究以评估绒毛表面积对 吸收和表面水解。 这些研究的数据可以 与患有肠道疾病的受试者进行比较以确定 如果腔内搅拌不足会导致吸收不良 肠道疾病患者。 2) 分别确定产生H2和消耗H2的作用 生物体：a) H2 产量非常高或非常低的受试者 b) 适应高纤维饮食或乳糖酶的受试者 适应高乳糖饮食的缺陷受试者。 H2是主要 肠胃气的组成部分，从而了解这些因素 调节肠道中 H2 的积累对于理解这一点很重要 肠胃胀气的发病机制和潜在的治疗方法。 摄入高剂量纤维或乳糖的受试者最初会出现 严重的胀气症状，持续摄入可改善 食品。 这种改进似乎反映了一种适应 产气植物群的研究，这些研究将确定是否 产生 H2 或消耗 H2 的生物体的变化涉及 这种适应。 3) 利用肺泡空气中一氧化碳 (CO) 的测量来 评估红细胞 (RBC) 周转率。 目前还没有 简单、快速地检测红细胞周转率，建议 针对环境 PCO 校正的肺泡 PCO 评估将 为红细胞存活提供临床上有用的测试。 4) 利用基质释放 CO 的测量作为衡量 氧化损伤。 拟议的研究将使用果糖作为测试 化合物： a) 识别参与该氧化的碳 b) 测试各种生物的氧化-抗氧化活性 液体。 氧化损伤对健康具有广泛的影响，并且 一氧化碳释放似乎是这种损伤的独特标志。