ENDOTHELIN AND RECEPTOR GENE EXPRESSION IN HYPOXIA

缺氧时内皮素和受体基因表达

• 批准号: 6183485
• 负责人: Yiu-Fai Chen
• 金额: $ 23.07万
• 依托单位: UNIVERSITY OF ALABAMA AT BIRMINGHAM
• 依托单位国家: 美国
• 财政年份: 1993
• 资助国家: 美国
• 起止时间: 1993-05-15 至 2002-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6183485
• 关键词: cellular pathology; endocrine pharmacology; endothelin; gel mobility shift assay; gene expression; genetic regulatory element; genetically modified animals; hormone receptor; hypoxia; immunocytochemistry; in situ hybridization; laboratory mouse; laboratory rat; pulmonary hypertension; receptor binding; receptor expression; respiratory pharmacology; tissue /cell culture; transcription factor; vascular endothelium; vascular smooth muscle

DESCRIPTION (Adapted from the applicant's abstract): The goal of this research is elucidate the role of endothelin-1 (ET-1) and ET receptors in hypoxia-induced pulmonary hypertension. Results of studies over the last 4 years have confirmed the hypothesis that ET-1 gene expression and ET-1 synthesis are selectively enhanced in lungs of rats exposed to hypoxia. Moreover, studies have confirmed that gene expression of the ET-1 receptors, ET-A and ET-B, is concomitantly enhanced in lungs of these animals. Hypoxia-induced upregulation of ET-1, ET-A and ET-B gene expression and ET-1 release have all paralleled functional and histopathologic evidence of the development of pulmonary hypertension. It is believed that ET-1, generated in conditions of hypoxia, acts via a paracrine mechanism on pulmonary ET-A receptors and, through its interaction, plays a fundamental etiologic role in hypoxia-induced pulmonary vasoconstriction, vascular remodelling, and maintenance of chronic pulmonary hypertension. Recently these investigators have demonstrated that selective ET-A receptor antagonists and a combined ET-A+ET-B receptor antagonist can both prevent and reverse acute and chronic hypoxia-induced pulmonary vasoconstriction and pulmonary hypertension. These data define a role for ET-1 as an important mediator of hypoxia-induced pulmonary hypertension. The specific aims of the current proposal are: 1) To test the hypothesis that ET-1 contributes to acute and chronic hemodynamic and structural adaptations to hypoxia in the rat by activating both ET-A and ET-B receptors. 2) To determine the cellular sites of ET-1 and ET-A and ET-B receptor gene expression under control conditions and in response to hypoxia. 3) To define the cis-regulatory element(s) in the 5' flanking region of the ET-1 gene involved in amplifying transcription of the ET-1 gene during exposure to hypoxia. 4) To identify and characterize the hypoxia-responsive transcription factor protein(s) that regulate ET-1 gene expression in response to hypoxia. Sprague-Dawley rats exposed to hypoxia (10 percent O2 at 1 atm.) or room air will be studies for Specific Aims 1 and 2. Transgenic mice harboring a human prepro-ET-1 promoter/luciferase reporter gene will be studied in Specific Aim 2. Cultured endothelial and smooth muscle cells derived from human and rat pulmonary microvessels and systemic vascular beds will be studied in Specific Aims 3 and 4.

描述（改编自申请人的摘要）：本项目的目标 研究阐明内皮素-1 (ET-1) 和 ET 受体在 缺氧引起的肺动脉高压。 过去4年的研究结果 多年来已经证实了 ET-1 基因表达和 ET-1 的假设 暴露于缺氧的大鼠肺部的合成选择性增强。 此外，研究已证实 ET-1 受体的基因表达， ET-A 和 ET-B 在这些动物的肺部同时增强。 缺氧诱导 ET-1、ET-A 和 ET-B 基因表达以及 ET-1 上调 释放具有所有平行的功能和组织病理学证据 肺动脉高压的发展。 据信 ET-1 产生 在缺氧条件下，通过旁分泌机制作用于肺 ET-A 受体，并通过其相互作用发挥基本的病因作用 缺氧引起的肺血管收缩、血管重塑 维持慢性肺动脉高压。 最近这些调查人员 已经证明选择性 ET-A 受体拮抗剂和联合药物 ET-A+ET-B受体拮抗剂可预防和逆转急、慢性 缺氧引起的肺血管收缩和肺动脉高压。 这些数据定义了 ET-1 作为重要调节者的作用 缺氧引起的肺动脉高压。 当前的具体目标 建议是： 1) 检验 ET-1 有助于急性和 大鼠对缺氧的慢性血流动力学和结构适应 激活 ET-A 和 ET-B 受体。 2) 确定蜂窝位置 对照条件下 ET-1、ET-A 和 ET-B 受体基因表达的变化 以及对缺氧的反应。 3) 定义顺式调节元件 ET-1 基因的 5' 侧翼区域参与放大转录 暴露于缺氧期间 ET-1 基因的变化。 4) 识别和 描述缺氧反应转录因子蛋白的特征 调节 ET-1 基因表达以应对缺氧。 斯普拉格-道利大鼠 暴露于缺氧（1 atm 下 10% O2）或室内空气中的情况将被研究 具体目标 1 和 2. 携带人类 prepro-ET-1 的转基因小鼠 启动子/荧光素酶报告基因将在具体目标 2 中进行研究。 培养的源自人和大鼠的内皮细胞和平滑肌细胞 将研究肺微血管和全身血管床 具体目标 3 和 4。