Takahashi K
Department of Molecular Biology and Applied Physiology, Tohoku University School of Medicine, Sendai, Japan.
Tohoku J Exp Med. 2001 Feb;193(2):79-114. doi: 10.1620/tjem.193.79.
In the last several decades, the concept of "endocrinology" has been greatly changed. One major change was due to the discovery of peptide hormones secreted by the organs that were not "classical" endocrine organs. For example, corticotropin-releasing hormone and many neuropeptides are secreted by the neurons, atrial natriuretic peptide by the heart, endothelin-1 by the vascular endothelial cells, and leptin by the adipose tissues. Now, the brain, heart, vascular tissue and adipose tissue can be considered to be endocrine organs. Cardiovascular diseases and obesity are therefore important targets of the endocrine research. Adrenomedullin is a potent vasodilator peptide consisting of 52 amino acids. It was originally discovered from a human pheochromocytoma, and belongs to the calcitonin gene-related peptide (CGRP) family. Adrenomedullin is produced and secreted by various types of cells, for example, vascular endothelial and smooth muscle cells, cardiomyocytes, fibroblasts, macrophages, neurons, glial cells, and retinal pigment epithelial cells. Such ubiquitous expression has not been observed in other neuropeptides, including neuropeptide Y and CGRP. Expression of adrenomedullin is induced by hypoxia and proinflammatory cytokines. In addition to vasodilator actions, this peptide has central inhibitory actions on water drinking and salt appetite, effects on the secretion of some hormones and cytokines, inotropic actions and effects on cell growth and apoptosis. Adrenomedullin is produced by various non-endocrine tumors, as well as endocrine tumors, and acts as a growth stimulatory factor for the tumor cells. Adrenomedullin seems to be involved in the pathophysiology of many diseases, including ischemic heart diseases, inflammatory diseases, tumors, and even eye diseases. The adrenomedullin research implies that "the neuroendocrine system" exists in much broader types of cells than previously thought, and that the endocrine research is able to contribute to the understanding of the pathophysiology of many diseases.
在过去几十年里，“内分泌学”的概念发生了巨大变化。一个主要变化是由于发现了并非“经典”内分泌器官的组织所分泌的肽类激素。例如，促肾上腺皮质激素释放激素和许多神经肽由神经元分泌，心钠素由心脏分泌，内皮素 -1由血管内皮细胞分泌，瘦素由脂肪组织分泌。如今，大脑、心脏、血管组织和脂肪组织都可被视为内分泌器官。因此，心血管疾病和肥胖是内分泌研究的重要目标。肾上腺髓质素是一种由52个氨基酸组成的强效血管舒张肽。它最初是从人嗜铬细胞瘤中发现的，属于降钙素基因相关肽（CGRP）家族。肾上腺髓质素由多种类型的细胞产生和分泌，例如血管内皮和平滑肌细胞、心肌细胞、成纤维细胞、巨噬细胞、神经元、神经胶质细胞和视网膜色素上皮细胞。在包括神经肽Y和CGRP在内的其他神经肽中未观察到这种普遍存在的表达。肾上腺髓质素的表达受缺氧和促炎细胞因子诱导。除血管舒张作用外，这种肽对饮水和盐食欲有中枢抑制作用，对某些激素和细胞因子的分泌有影响，有正性肌力作用以及对细胞生长和凋亡有作用。肾上腺髓质素由各种非内分泌肿瘤以及内分泌肿瘤产生，并作为肿瘤细胞的生长刺激因子。肾上腺髓质素似乎参与了许多疾病的病理生理学过程，包括缺血性心脏病、炎症性疾病、肿瘤，甚至眼部疾病。肾上腺髓质素的研究表明，“神经内分泌系统”存在于比以前认为的更广泛类型的细胞中，并且内分泌研究有助于理解许多疾病的病理生理学。
