REGULATION OF ANF AND BNP IN CARDIAC HYPERTROPHY

ANF 和 BNP 在心肌肥厚中的调节

• 批准号: 2211298
• 负责人: MARGOT CLAIRE LAPOINTE
• 金额: $ 6.37万
• 依托单位: HENRY FORD HEALTH SYSTEM
• 依托单位国家: 美国
• 财政年份: 1994
• 资助国家: 美国
• 起止时间: 1994-08-01 至 1999-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/2211298
• 关键词: atrial natriuretic peptide; chemical structure function; gel mobility shift assay; gene expression; genetic promoter element; genetic transcription; northern blottings; polymerase chain reaction; posttranscriptional RNA processing; reporter genes; saluretic; tissue /cell culture; transcription factor; transfection; vasoconstrictors; ventricular hypertrophy

Atrial natriuretic factor (ANF) and brain natriuretic peptide (BNP) have vasodepressor effects, while in the kidney they have potent natriuretic and diuretic activity. Although they have similar biological activity, each hormone has distinct features, most importantly differences in DNA regulatory sequences involved in gene expression. In adult hearts, the gene for ANF is preferentially expressed in the atria, and ventricular expression is less than 5% of the whole heart. In contrast, ventricular BNP mRNA represents greater than 70% of whole heart levels. ANF and BNP mRNA are augmented in the ventricle under various conditions of volume and pressure overload, including hypertension and heart failure. Given that the BNP gene is expressed primarily in the ventricles while the ratio of BNP to ANF is different in atria and ventricles there must be clear differences in the way ANF and BNP synthesis are regulated. The objective of this proposal is to define transcriptional and post-transcriptional mechanisms involved in differential regulation of the ANF and BNP genes during cardiac hypertrophy using 2 in vitro models of hypertrophy: adult feline cardiocytes stimulated to beat with isoproterenol and phenylephrine- or PMA-stimulated neonatal ventricular cardiocytes. Specifically, the hypotheses to be tested are that: 1) there are differences in the rates of transcription of the ANF and BNP genes, and cis-acting regulatory elements in the 5' flanking sequences (fS) of the BNP gene are distinct from those characterized for the ANF gene in neonatal cardiocytes; 2) during cardia hypertrophy, re-expression of the ANF and BNP genes involves cis-acting regulatory regions distinct from those involved in normal tissue-specific gene expression; 3) different trans-acting regulatory proteins affect ANF and BNP gene expression in normal vs. hypertrophied cardiac myocytes; and 4) BNP mRNA stability is regulated differently in normal and hypertrophied ventricles. These studies will employ cell culture models of hypertrophy, Northern blot of mRNA, transfection of chimeric promoter-reporter gene constructions, enzyme assays (luciferase and beta-galactosidase), polymerase chain reaction (PCR), DNA- and RNA-protein gel shift, and in vivo analysis of regulator elements (in vivo injection of DNA). Thus they will provide a detailed analysis of differences in ANF and BNP gene regulation and help us understand the relevance of each hormone in disease, such as hypertension and hypertrophy.

心房钠尿因子（ANF）和脑钠尿肽（BNP） 血管抑制作用，而在肾脏中则具有有效的利钠作用 和利尿活性。尽管它们具有相似的生物活性， 每种激素都有独特的特征，最重要的是 DNA 的差异 参与基因表达的调控序列。在成年人的心中， ANF 基因优先在心房和心室表达 表达量小于整个心脏的5%。相比之下，心室 BNP mRNA 占整个心脏水平的 70% 以上。 ANF 和 BNP 在不同的容量条件下，mRNA 在心室中增加 压力超负荷，包括高血压和心力衰竭。鉴于 BNP 基因主要在心室表达，而 BNP与ANF在心房和心室的不同，必须明确 ANF 和 BNP 合成的调节方式存在差异。目标 该提案的目的是定义转录和转录后 ANF 和 BNP 基因差异调节的机制 在心脏肥大期间使用 2 种体外肥厚模型：成人 用异丙肾上腺素刺激猫心肌细胞跳动 去氧肾上腺素或 PMA 刺激的新生儿心室心肌细胞。 具体来说，要检验的假设是：1） ANF 和 BNP 基因转录率的差异，以及 5' 侧翼序列 (fS) 中的顺式作用调控元件 BNP 基因与 ANF 基因的特征不同 新生儿心肌细胞； 2）在心肌肥厚期间，重新表达 ANF 和 BNP 基因涉及与不同的顺式作用调节区域 那些参与正常组织特异性基因表达的； 3）不同 反式作用调节蛋白影响 ANF 和 BNP 基因表达 正常心肌细胞与肥大心肌细胞； 4) BNP mRNA 稳定性为 正常心室和肥厚心室的调节不同。这些 研究将采用肥大细胞培养模型、Northern blot mRNA，嵌合启动子-报告基因构建的转染， 酶测定（荧光素酶和 β-半乳糖苷酶）、聚合酶链 反应 (PCR)、DNA 和 RNA 蛋白质凝胶位移以及体内分析 调节元件（体内注射DNA）。因此他们将提供一个 详细分析ANF和BNP基因调控差异及帮助 我们了解每种激素与疾病的相关性，例如 高血压和肥大。