Search for novel peptides to increase rat platelet cAMP.

利用提高大鼠血小板cAMP活性的检测系统，我们在人嗜铬细胞瘤提取物中发现了一种新的降压肽，命名为“肾上腺髓质素”。它在几个血管系统中具有有效和持久的血管扩张作用。除肾上腺髓质素外，另一种降压肽，称为“肾上腺髓质素前n端20肽”（PAMP），被发现可由肾上腺髓质素前体加工而成。虽然最初是从人嗜铬细胞瘤组织和猪肾上腺髓质中分离出来的，但肾上腺髓素mRNA在包括心血管组织在内的几种外周器官中高度表达。结合心血管疾病患者血浆免疫反应性肾上腺髓质素水平的显著升高，肾上腺髓质素是调节血压和循环的新因子。此外，肾上腺髓质素mRNA的普遍表达表明其具有多种生物学功能，并存在一种新的循环控制系统。

Using the assay system which monitor the activity to increase rat platelet cAMP,we have discovered a novel hypotensive peptide, designated "adrenomedullin", in human pheochromocytoma extract. It has potent and long-lasting vasodilator effects in several vascular systems. In addition to adrenomedullin, another hypotensive peptide, termed "proadrenomedullin N-terminal 20 peptide" (PAMP) is found to be processed from the adrenomedullin precursor. Although initially isolated from human pheochromocytoma tissue and porcine adrenal medullae, adrenomedullin mRNA is highly expressed in several peripheral organs including cardiovascular tissues. Taken together with a significant increase in plasma immunoreactive adrenomedullin levels in patients with cardiovascular diseases, adrenomedullin is a novel factor regulating blood pressure and circulation. Futhermore, ubiquitous expression of adrenomedullin mRNA indicates its various biological functions as well as the existence of a novel circulation control system.