GASTRIC ACID SECRETION, REGULATION OF K+ TRANSPORTERS

胃酸分泌、钾离子转运蛋白的调节

• 批准号: 3232623
• 负责人: EDWIN C RABON
• 金额: $ 12.71万
• 依托单位: UNIVERSITY OF CALIFORNIA LOS ANGELES
• 依托单位国家: 美国
• 财政年份: 1984
• 资助国家: 美国
• 起止时间: 1984-08-01 至 1992-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3232623
• 关键词: adenosinetriphosphatase; gastric acid; gastric juice; laboratory rabbit; liposomes; phospholipids; potassium chloride; second messengers; secretion

The long term goal of this study is to define the K+ transport mechanisms used to regulate the transcellular flow of K+ during gastric acid secretion. We have developed an assay of 86Rb- flux which discriminates ATPase and conductance mediated K+ transport to characterize secretory stimulusdependent K+ movement across the basolateral (BLM) and secretory (SM) membranes of vesicle preparations and intact and permeabilized isolated parietal cells of the New Zealand white rabbit. The K+ conductance will be characterized will respect to (i) specific stimulus dependence (ii) cationic selectivity (iii) inhibitor specificity (iii) regulation by specific second messenger mediators. The stimulus response of the Na, K-ATPase will be determined in the isolated cell preparation by the (3H) ouabain binding assay of Hootman and Williams and compared with that of the BLM K+ conductance (J. Physiol (1985) 360:121-134). The K+ conductance of the SM will be solubilized and functionally reconstituted to extend the characterization of this peptide with respect to (i) disenness of inhibitors and physiological moderators and (ii) to begin the initial purfication of the conductance peptide. The appearance of the K+ conductance and specific peptides labeled with the use dependent H,K-ATPase inhibitor (14C) omeprazole will be correlated in stimulated and resting SM preparations to distinguish between possible mechanisms of activation (i.e. appearance of the potassium conductance in parallel with the H,K-ATPase) by a membrane fusion process involving the insertion of a K+ conductance into the SM or covalent modification of an inactive conductance peptide always present in the membrane. These studies suggest that K+ conductances are targets for the physiological regulation of gastric acid secretion. The model system and assays developed here could provide important tools for the study of the pharmacology of the K+ conductance peptide as a means of control of gastric acid secretion.

这项研究的长期目标是定义K+转运 细胞内钾离子跨细胞流动的调节机制 胃酸分泌。我们已经开发了一种86Rb-通量的分析方法 区分ATPase和电导介导的K+ 用于表征分泌刺激依赖的K+的转运 跨基底外侧区(BLM)和分泌区(SM)的运动 囊泡制剂和膜的完好性和渗透性 新西兰大白兔分离的壁细胞。K+ 电导将根据(I)具体情况进行表征 刺激依赖性(II)阳离子选择性(III)抑制剂 特异性(III)由特定的第二信使调节 调解人。Na，K-ATPase的刺激反应将是 分离细胞制剂中(~3H)哇巴因的测定 Hootman和Williams的结合实验及与之的比较 BLMK+电导(J.Physiol(1985)360：121-134)。K+ SM的导电性将被增溶和功能化 重组以扩展该多肽的特性 关于(I)抑制剂和生理调节剂的无效性 以及(Ii)开始电导肽的初始纯化。 钾离子电导和特异性多肽的出现 用依赖使用的H，K-ATPase抑制剂(14C)标记 奥美拉唑在刺激性和静息性SM中的相关性 为区分可能的机制做好准备 活化(即，钾电导出现在 与H，K-ATPase平行)通过膜融合过程 涉及将K+电导插入SM或 非活性电导肽Always的共价修饰 存在于细胞膜中。这些研究表明，K+ 电导是生理调节的靶标。 胃酸分泌。已开发的模型系统和检测方法 这可能会为研究这一问题提供重要工具 K+电导肽作为一种治疗手段的药理学 控制胃酸分泌。