The studies for expression and secretion of adrenomedullin and its signal transduction.

肾上腺髓质素的表达、分泌及其信号转导的研究。

• 批准号: 08457269
• 负责人: KANGAWA Kenji
• 金额: $ 4.93万
• 依托单位: NATIONAL CARDIOVASCULAR CENTER RESEARCH INSTITUTE
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 1996
• 资助国家: 日本
• 起止时间: 1996 至 1997
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-08457269/
• 关键词: adrenomedullin (AM); vasorelaxant peptide; cardiovascular disease; human aortic endothelial cells (HAEC); AM gene expression; 5'-flanking region; NF-IL6; PAMP-12 (PAMP[9-20]); アドレノメデュリン(AM); PAMP; 遺伝子発現調節; 敗血症ショック; イヌAM前駆体構造; 血管; 消化管; エンドトキ

Adrenomedulin (AM) is a potent vasorelaxant peptide recently isolated from human pheochromocytoma tissue, and is structurally a member of CGRP family. mRNA of AM is highly expressed in several tissues including heart, lung, kindey and vascular wall as well as adrenal medulla. In this project, we have studied the expression and secretion of AM and its signal transduction.To investigate the sites of production and secretion of AM in heart failure, we measured plasma adrenomedullin levels and peptide and mRNA levels of adrenomedullin in various tissues in rats with heart failure. We also examined whether the heart actually secretes AM into the circulation in patients with heart failure. Plasma AM levels were increased in heart failure rats, correlating with ventricular weight. Tissue AM peptide and mRNA levels were increased in the heart and lungs, but not kidney or adrenals of rats with heart failure. Plasma AM levels were higher in the coronary sinus than in the aorta in patients with h … More eart failure. These results suggest that plasma adrenomedullin levels are increased in heart failure in proportion to its severity and that cardiac production and secretion of adrenomedullin is increased in heart failure rats. Lungs may be another site for increased production of adrenomedullin in heart failure rats.To elucidate the regulatory mechanism of human AM gene expression, functional elements of 5'-flanking region of AM gene were examined in cultured human aortic endothelial cells (HAEC) by using a luciferase vector. The promoter activity of AM gene 5'-flanking DNA was reduced by losing NF-IL6 site at -85 to -93 bp, AP-2 sites at -33 to -68 bp and TATA box at -21 to -26 bp. These cis-acting elements are supposed to participate in the transcriptional regulation of human AM gene in ECIt is still unclear whether AM-induced vasodilation is endothelium-dependent. Endothelium-denudation of the aortic ring suppressed the dilatory response to AM.Furthermore, pretreatments of the rat aortic rings and isolated kidney with E-4021, a cGMP specific phosphodiesterase inhibitor, significantly enhanced AM-induced vasodilation, suggesting an important role of NO-cGMP in the vascular action of AM.Proadrenomedullin N-terminal 20 peptide (PAMP-20) is a potent hypotensive peptide processed from the AM precursor. We have identified PAMP-12 (PAMP[9-20]) porcine adrenal medulla as a major product of the AM precursor, and demonstrated that it exhibits a potent hypotensive action. Although the existence of a specific receptors for PAMP remains obscure, PAMP-12 might share a biological functin with PAMP-20 Less

肾上腺髓质素（AM）是最近从人嗜铬细胞瘤组织中分离到的一种有效的血管松弛肽，在结构上是CGRP家族的成员。AM mRNA在心脏、肺、肾、血管壁及肾上腺髓质等组织中均有高表达。在这个项目中，我们研究了AM的表达和分泌及其信号转导。为了研究AM在心力衰竭中产生和分泌的部位，我们测量了心力衰竭大鼠血浆肾上腺髓质素水平和各组织肾上腺髓质素肽和mRNA水平。我们还研究了心力衰竭患者的心脏是否真的会向血液循环中分泌AM。心力衰竭大鼠血浆AM水平升高，与心室重量相关。心衰大鼠心脏和肺组织AM肽和mRNA水平升高，肾脏和肾上腺组织AM肽和mRNA水平升高。心衰患者冠状动脉窦的血浆AM水平高于主动脉。这些结果表明，心力衰竭大鼠血浆肾上腺髓质素水平随其严重程度成比例升高，心脏肾上腺髓质素的产生和分泌增加。肺脏可能是心力衰竭大鼠肾上腺髓质素分泌增加的另一个部位。为了阐明人AM基因表达的调控机制，利用荧光素酶载体，在体外培养的人主动脉内皮细胞（HAEC）中检测AM基因5′-侧翼区功能元件。AM基因5'侧DNA启动子活性降低，NF-IL6位点在-85 ~ -93 bp， AP-2位点在-33 ~ -68 bp， TATA box位点在-21 ~ -26 bp。这些顺式作用元件被认为参与了人AM基因在eci中的转录调控。AM诱导的血管舒张是否依赖于内皮细胞尚不清楚。主动脉环内皮剥脱抑制AM的扩张性反应。此外，用cGMP特异性磷酸二酯酶抑制剂E-4021预处理大鼠主动脉环和离体肾脏，可显著增强AM诱导的血管舒张，提示NO-cGMP在AM的血管作用中起重要作用。肾上腺髓素前n端20肽（PAMP-20）是一种由AM前体加工而成的有效降压肽。我们已经确定PAMP-12 （PAMP[9-20]）是猪肾上腺髓质AM前体的主要产物，并证明它具有有效的降压作用。尽管PAMP特异性受体的存在尚不清楚，但PAMP-12可能与PAMP-20 Less具有相同的生物学功能

项目成果

T.Sumimoto, T.Nishikimi, M.Mukai, K.Matsuzaki, E.Murakami, S.Takishita, A.Miyata, K.Kangawa and H.Masuo: "Plasma adrenomedullin concentrations and cardiac and arterial hypertrophy in hypertension." Hypertension. 30. 741-745 (1997)

T.Sumimoto、T.Nishikimi、M.Mukai、K.Matsuzaki、E.Murakami、S.Takishita、A.Miyata、K.Kangawa 和 H.Masuo：“高血压中的血浆肾上腺髓质素浓度与心脏和动脉肥大。”

T.Nishikimi, S.Nagata, T.Sasaki, S.Tomimoto, K.Kimura, H.Matsuoka, S.Takishita, K.Kitamura, A.Miyata, K.Kangawa, H.Matsuo: "Plasma concentrations of adrenomedullin correlate with the extent of pulmonary hypertansion in patients with mitral stenosis." Hear

T.Nishikimi、S.Nagata、T.Sasaki、S.Tomimoto、K.Kimura、H.Matsuoka、S.Takishita、K.Kitamura、A.Miyata、K.Kangawa、H.Matsuo：“肾上腺髓质素的血浆浓度与

Ikenouchi K.,et al.: "Negative inotropic effect of adrenomedullin in isolated adult rabbit cardiac ventricular myocytes." Circulation. 95. 2318-2324 (1997)

Ikenouchi K. 等人：“肾上腺髓质素对离体成年兔心室肌细胞的负性肌力作用。”

Nishio K,et al.: "Elevated plasma levels of adrenomedullin correlate with relaxation of vascular tone in patients with septic shock." Crit.Care Med.25. 935-957 (1997)

Nishio K 等人：“脓毒性休克患者血浆肾上腺髓质素水平升高与血管张力松弛相关。”

T.Ishimitsu, T.Nishikimi, H.Matsuoka, K.Kangawa, K.Kitamura, J.Minami, H.Matsuo and T.Eto: "Behavior of adrenomedullin during acute and chronic salt loading in normotensive and hypertensive subjects." Clin.Sci.91. 293-298 (1996)

T.Ishimitsu、T.Nishikimi、H.Matsuoka、K.Kangawa、K.Kitamura、J.Minami、H.Matsuo 和 T.Eto：“正常血压和高血压受试者急性和慢性盐负荷期间肾上腺髓质素的行为”。