ENDOTHELIN AND RECEPTOR GENE EXPRESSION IN HYPOXIA

缺氧时内皮素和受体基因表达

• 批准号: 6056257
• 负责人: Yiu-Fai Chen
• 金额: $ 22.4万
• 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/6056257
• 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）：本研究的目标 研究阐明内皮素-1（ET-1）及其受体在 缺氧性肺动脉高压 过去4年的研究结果 多年的研究证实了ET-1基因表达和ET-1 合成在暴露于缺氧的大鼠肺中选择性增强。 此外，研究已经证实ET-1受体的基因表达， ET-A和ET-B在这些动物的肺中伴随增强。 缺氧诱导ET-1、ET-A和ET-B基因表达上调及ET-1 释放所有的神经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， 在缺氧诱导的肺血管收缩、血管重塑和 维持慢性肺动脉高压。 最近，这些研究人员 已经证明选择性ET-A受体拮抗剂和组合的 ET-A+ET-B受体拮抗剂可预防和逆转急性和慢性炎症， 缺氧诱导的肺血管收缩和肺动脉高压。 这些数据定义了ET-1作为一种重要的调节剂的作用， 缺氧性肺动脉高压 当前的具体目标 建议：1）验证ET-1参与急性和慢性炎症的假设， 慢性血流动力学和结构适应大鼠缺氧 激活ET-A和ET-B受体。 2)为了确定手机的位置 对照条件下ET-1和ET-A和ET-B受体基因表达 以及对缺氧的反应。 3)为了定义顺式调节元件， 参与扩增转录的ET-1基因的5'侧翼区 ET-1基因在缺氧环境中的表达。 4)识别和 表征低氧应答性转录因子蛋白， 调节ET-1基因表达以响应缺氧。 Sprague-Dawley大鼠 暴露于缺氧（10% O2，1 atm.）或室内空气将被研究 具体目标1和2。 携带人ET-1前体的转基因小鼠 启动子/荧光素酶报告基因将在特异性目的2中研究。 培养的人和大鼠内皮细胞和平滑肌细胞 肺微血管和全身血管床将在 具体目标3和4。