Omatsu S, Tomoyoshi T
Department of Urology, Shiga University of Medical Science.
Hinyokika Kiyo. 1997 Feb;43(2):109-14.
To elucidate the role of endothelin (ET) in the kidney, we immunohistochemically examined the precise distribution of various forms of ET-peptides in the rat kidney, using specific polyclonal antibodies to each precursor (Big ET-1, Big ET-2 and Big ET-3), and anti-mature ET antibodies. Immunoreactivity of Big ET-1 was localized mainly in some vascular endothelial cells, glomerular mesangial cells and epithelial cells of proximal tubules in the renal cortex and inner-medullary collecting ducts. The distribution of immunoreactivity for mature ETs was similar to those of Big ET-1. These observations suggest that mature ET-1 after conversion from Big ET-1 is secreted from these cells. Since similar findings were obtained using anti-Big ET-2 and anti-Big ET-3 antibodies, these two isopeptides are also considered to have certain physiological actions in the kidney. Immunohistochemical studies for ET-A receptor were also performed. The distribution of this receptor was similar to those of Big ETs and mature ETs. This suggests that secreted ET acts on adjacent cells in an autocrine/paracrine manner in the kidney.
为阐明内皮素（ET）在肾脏中的作用，我们使用针对每种前体（大ET-1、大ET-2和大ET-3）的特异性多克隆抗体以及抗成熟ET抗体，通过免疫组织化学方法检测了大鼠肾脏中各种形式ET肽的精确分布。大ET-1的免疫反应性主要定位于肾皮质和髓质内集合管的一些血管内皮细胞、肾小球系膜细胞以及近端小管的上皮细胞。成熟ET的免疫反应性分布与大ET-1相似。这些观察结果表明，从大ET-1转化而来的成熟ET-1是从这些细胞分泌的。由于使用抗大ET-2和抗大ET-3抗体也获得了类似的结果，因此这两种异肽也被认为在肾脏中具有某些生理作用。我们还进行了ET-A受体的免疫组织化学研究。该受体的分布与大ET和成熟ET相似。这表明分泌的ET在肾脏中以自分泌/旁分泌方式作用于相邻细胞。
