INTESTINAL FUNCTION IN A HIBERNATOR: ADAPTIVE CHANGES

冬眠状态下的肠道功能：适应性变化

• 批准号: 3463278
• 负责人: Hannah V. Carey
• 金额: $ 6.41万
• 依托单位: UNIVERSITY OF WISCONSIN-MADISON
• 依托单位国家: 美国
• 财政年份: 1989
• 资助国家: 美国
• 起止时间: 1989-04-01 至 1991-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3463278
• 关键词: DNA; brush border membrane; chemical structure function; circadian rhythms; environmental adaptation; epithelium; fasting; gastrointestinal absorption /transport; gastrointestinal function; gastrointestinal pharmacology; glucose transport; hibernation; ion transport; membrane permeability; membrane structure; nutrition related tag; peptides

The intestinal mucosa of the hibernator appears to maintain absorptive capacity until spring emergence despite the lack of luminal nutrition during hibernation. In contrast, fasting in non- hibernating mammals results in a significant reduction in absorptive function after 3 days. The aims of this project are to determine if seasonal variations in intestinal nutrient and electrolyte transport occur during the annual cycle for the hibernating ground squirrel, and to identify the mechanisms and signals that lead to adaptive regulation of intestinal transport function during the annual cycle. Intestinal sugar and electrolyte transport will be assessed in ground squirrels during the spring, summer, fall and winter. Winter studies will involve hibernating squirrels as well as squirrels that were allowed to remain active and feeding in a warm room. Transepithelial fluxes of glucose, sodium and chloride will be measured in jejunal segments set up in modified Ussing-type chambers. Glucose influx across the brush border membrane will be measured to determine if changes in the number of glucose carrier sites or the affinity of glucose for its carrier are responsible for adaptive changes in transport function. Intestinal mass and structure in each group of squirrels will be estimated by measuring the weights, protein and DNA content, and villus and crypt dimensions of mucosa harvested from segments adjacent to those used in the physiological experiments. Blood and tissue samples will be collected from squirrels used in the transport experiments for later analysis of peptides and other messengers that might be involved in seasonal changes in intestinal structure and function. Pharmacological and histological tools will be used to identify the signals that mediate the mucosal response to enteric neural stimulation. These studies are expected to provide insight into the natural rhythms of the gastrointestinal tract and the signals that lead to adaptive regulation during hibernation.

冬眠的肠粘膜似乎保持 吸收能力直到春季出现，尽管缺乏 休眠期间的腔内营养。 相反，在非 - 禁食 冬眠的哺乳动物导致显着降低 3天后吸收功能。 该项目的目的是 确定肠道营养素和 电解质运输发生在年周期中 冬眠地松鼠，并确定机制和 导致自适应调节肠运输的信号 在年周期中的功能。 肠糖和电解质 春季将在地松鼠中评估运输 夏季，秋冬。 冬季研究将涉及冬眠 松鼠以及允许保持活跃的松鼠 并在温暖的房间里喂食。 葡萄糖的旋转通量， 钠和氯化物将在设置的空肠段中测量 修改了Ussing-Type Chambers。 整个刷子的葡萄糖涌入 将测量边界膜以确定 葡萄糖载体位点的数量或葡萄糖的亲和力 载体负责运输功能的自适应变化。 每组松鼠的肠质量和结构将是 通过测量重量，蛋白质和DNA含量来估计 绒毛和粘膜的粘膜尺寸 与生理实验中使用的段相邻。 将从使用的松鼠收集血液和组织样本 以后分析肽和其他的运输实验 可能参与季节性变化的使者 肠结构和功能。 药理和 组织学工具将用于识别介导的信号 对肠神经刺激的粘膜反应。 这些研究 期望能够深入了解 胃肠道和导致自适应的信号 冬眠期间的调节。