The systematic survey for novel vasoactive peptides produced in the adrenal medulla.

哺乳动物的血液循环是由涉及几个神经和激素因素的微妙机制调节的。血管活性肽包括血管紧张素、心钠素和内皮素，是心血管系统中重要的调节因子。1993年我们发现了肾上腺髓质素（adrenomedullin），并发现了另一种由肾上腺髓质素前体产生的高血压肽肾上腺髓质素前体N末端20肽（proadrenomedullin N-terminal 20 peptide，PAMP）。本研究对肾上腺髓质素异肽和PAMP进行了系统的研究。利用放射免疫分析法测定肾上腺髓质素的环状结构，分离并测定了内源性肽肾上腺髓质素（11-26）。合成的肾上腺髓质素（11-26）在未麻醉大鼠体内产生剂量依赖性的强升压反应，我们利用一种新的检测C-端酰胺结构的方法，分离了一个新的14个氨基酸的C-端酰胺化肽。这种肽被称为amidicin。脒霉素广泛分布于猪的组织中，尤其是在脑垂体、心室和脾脏中含量最高。脒霉素可能是一种新的参与循环调控的多肽。

Mammalian circulation is regulated by subtle mechanisms involving several neural and hormonal factors. Several vasoactive peptides including angiotensin, ANP and endothelin are important regulators in the cardiovascular system. For clarifying the intricacies of circulation control, it is important to discover still unidentified vasoactive peptide.We discovered adrenomedullin in 1993 and found another hypetensive peptide proadrenomedullin N-terminal 20 peptide (PAMP) which is produced from adrenomedullin precursor. In this study, we performed systematic survey for isopeptide of adrenomedullin and PAMP. Using the RIA for the ring structure of adrenomedullin, we isolated and determined adrenomedullin (11-26) as endogenous peptide. The synthetic adrenomedullin (11-26) produced dose-dependent strong pressor responses in unanesthetized rats in vivo.Using a novel method to detect a peptide with C-terminal amide structure, we isolated a novel 14 amino acids peptide where C-terminus was amidated. This peptide was termed amidicin. Amidicin is widely distributed in porcine tissue and is especially abundant in pituitary gland, cardiac ventricle and spleen. Amidicin may be a possible new peptide participating in circulation control.