Electrical and Pharmacological Properties of Freshly Isolated Single Smooth Muscle Cells

新鲜分离的单个平滑肌细胞的电学和药理学特性

• 批准号: 8819750
• 负责人: Joshua Singer
• 金额: $ 17.88万
• 依托单位: University of Massachusetts Medical School
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1989
• 资助国家: 美国
• 起止时间: 1989-03-01 至 1992-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=8819750&HistoricalAwards=false
• 关键词: Electrical; Pharmacological; Properties; Freshly; Isolated

The long term goals of this research program are to understand the function of ionic channels in the membrane of smooth muscle cells and their regulation by transmitters, ions, metabolites, second messengers, and membrane potential. Since ionic channels control the membrane potential, serve as one of the principal targets of neurotronsmitters and second messenger mechanisms, underlie the action potential, and govern calcium entry into the cell, they play a central role in the regulation of smooth muscle contraction. The experiments employ freshly dissociated cells from the stomach of the bullfrog, Bufo marinus. Emphasis will be placed on patch-clamp techniques to record both whole-cell and single-channel currents. The specific goals for which support is requested are studies of the mechanism of potassium channel activation by arachidonic acid and related fatty acids which has been observed in preliminary experiments. Studies will will be carried out to determine whether potassium channel activaton is caused by arachidonic acid and other fatty acids themselves or by metabolites derived from these fatty acids. A variety of compounds structurally related to arachidonic acid and other fatty acids will be examined to establish which structural features are required for the molecules to be effective in inducing potassium current. Possible endogenous agents that may be releasing the fatty acids will be sought and identified, and any additional effects of fatty acids on channels will be studied. The role of arachidonic acid and other fatty acids as second messengers in transmission of external signals to the biochemical machinery within cells has recently become the focus of attention in a number of cell systems. The preliminary observations of Drs. Singer and Walsh that these agents appear to affect ion channels in the membranes of smooth muscle cells suggest a previously unexpected mechanism by which the excitability and contractile activity of these cells may be modulated. The further analysis of these new observations may lead to important insights into the mechanisms of regulation of contraction of smooth muscle, and more generally into the mechanisms by which the permeability of cell membranes is regulated.

这项研究计划的长期目标是 了解离子通道在细胞膜中的功能， 平滑肌细胞及其通过递质，离子， 代谢物、第二信使和膜电位。 以来 离子通道控制膜电位，作为其中之一 神经电子发射器和第二信使的主要目标 机制，作为动作电位的基础，并管理钙 进入细胞后，它们在调节 平滑肌收缩。 实验采用新鲜的 从牛蛙的胃里分离出来的细胞，海蟾蜍。 重点将放在膜片钳技术，以记录这两个 全细胞和单通道电流。 具体目标为 所要求的支持是研究 花生四烯酸激活钾通道及相关 在初步实验中观察到的脂肪酸。 将进行研究以确定钾是否 通道激活是由花生四烯酸和其他脂肪酸引起的。 酸本身或由这些脂肪酸衍生的代谢物 acids. 各种化合物结构上与 花生四烯酸和其他脂肪酸将被检查， 确定所需的结构特征， 有效诱导钾电流的分子。 可能释放脂肪酸的内源性因子 将寻求和确定，以及任何额外的影响， 将研究通道上的脂肪酸。 花生四烯酸和其他脂肪酸作为第二 传递外部信号的信使， 细胞内的机制最近成为人们关注的焦点 在许多细胞系统中。 的初步意见 Singer和沃尔什博士认为这些药剂似乎会影响 平滑肌细胞膜中的通道表明， 以前意想不到的机制， 可以调节这些细胞的收缩活性。 的 对这些新观测结果的进一步分析可能会导致重要的 对收缩调节机制的深入了解， 平滑肌，更一般地说， 调节细胞膜的渗透性。