EPITHELIAL TRANSPORT: A MORPHOLOGICAL APPROACH

上皮运输：一种形态学方法

• 批准号: 3224427
• 负责人: RICHARD M HAYS
• 金额: $ 29.83万
• 依托单位: ALBERT EINSTEIN COLLEGE OF MEDICINE
• 依托单位国家: 美国
• 财政年份: 1976
• 资助国家: 美国
• 起止时间: 1976-05-01 至 1989-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3224427
• 关键词: adenosine triphosphate; adenylate cyclase; anesthetics; autoradiography; bioenergetics; cell membrane; cell water; choroid plexus; chromium; cyclic AMP; cytoskeleton; epithelium; erythrocyte membrane; erythrocytes; gastrointestinal system; halothane; hormone biosynthesis; hormone regulation /control mechanism; human tissue; ion transport; membrane permeability; metal oxide; methoxyflurane; osmosis; peritoneum; prostaglandins; radioimmunoassay; radiotracer; renal tubular transport; solute; urea; urinary bladder; vasopressins; water

Two projects are described in this application. Both emphasize the relation of cell structure to epithelial transport. 1. The action of ADH: a scanning and transmission electron microscopie study. We have been able to apply current high-resolution techniques in both scanning and transmission electron microscopy (SEM and TEM) to the problem of the intracellular action of antidiuretic hormone (ADH). We will use both SEM and TEM to determine in detail the structure of the terminal web of the toad bladder epithelial cell, and the specific filamentous attachments of the cytoplasmic tubules to the luminal membrane and surrounding cytoskeleton. These tubules fuse to the membrane in response to ADH, and deliver water-conducting particles to the membrane. We have proposed a "tilting" mechanism for tubule fusion, and will seek evidence for this mechanism. We will employ tannic acid-fixed sections, resinless sections and sections coated with ultrathin metal films in our SEM and TEM sections. We will identify specific cytoskeletal components by immunocytochemistry at the light and EM level. We will isolate and characterize the water-conducting particles. We will use our techniques in a study of the mammalian kidney, emphasizing glomerular cytoskeletal structure. 2. Autoradiography of diffusible solutes. Refinements in our system of "dry" autoradiography permit the study of the transport of water-soluble solutes such as urea across epithelia, and the effects of hormones and inhibitory agents on transport. These studies will now be extended to two new problems: the paracellular transport of ions and non-electrolytes across "leaky" epithelia, and the active transport of iodide by the choroid plexus. Both projects bring new techniques to the problem of epithelial transport. There is increasing interest in fusion and exocytosis in such phenomena as neurotransmission and hormone secretion; the ADH system under investigation in this application provides one of the most clear-cut examples of the relationship of the cytoskeleton to fusion. In the human kidney, glomerular filtration appears to be greatly influenced by the contractile properties of the mesangial cell and other cellular elements surrounding the basement membrane; these may be altered in important ways in renal disease. Our autoradiographic studies show cellular transport in a new way, and add to our understanding of water and electrolyte movement.

本申请中描述了两个项目。 两者都强调， 细胞结构与上皮转运的关系。 1.抗利尿激素作用的扫描和透射电镜观察 study. 我们已经能够将当前的高分辨率技术应用于 扫描和透射电子显微镜（SEM和TEM） 抗利尿激素（ADH）的细胞内作用的问题。 我们将 利用SEM和TEM来详细确定端子的结构 蟾蜍膀胱上皮细胞的网，和特定的丝状 细胞质小管与管腔膜的附着， 包围着细胞骨架 这些小管与细胞膜融合 转化为ADH，并将导水颗粒输送到膜上。 我们有 提出了一个“倾斜”机制的小管融合，并将寻求证据 对于这个机制。 我们将采用单宁酸固定部分，无树脂 在我们的SEM和TEM中， 路段 我们将通过以下方法鉴定特定的细胞骨架成分： 免疫细胞化学光、电镜观察。 我们将隔离， 表征导水颗粒。 我们将利用我们的技术 对哺乳动物肾脏的研究，强调肾小球细胞骨架 结构 2.可扩散溶质的放射自显影。 完善我们的系统， “干”放射自显影允许研究水溶性的 溶质如尿素穿过上皮，以及激素和 运输抑制剂。 这些研究现在将扩展到两个 新问题：离子和非电解质的细胞旁转运 穿过“渗漏”上皮，以及脉络膜对碘化物的主动转运 丛的 这两个项目都为上皮运输问题带来了新技术。 人们对融合和胞吐作用等现象越来越感兴趣， 神经传递和激素分泌;研究中的ADH系统 在本申请中提供了一个最明确的例子， 细胞骨架与融合的关系。 在人体肾脏中， 肾小球滤过率似乎受到收缩性肾小球滤过率的影响。 系膜细胞和周围其他细胞成分的性质 基底膜;这些可能在肾脏中以重要的方式改变 疾病 我们的放射自显影研究表明，在一个新的细胞运输 方法，并增加我们对水和电解质运动的理解。