Yabuki Akira, Taharaguchi Satoshi, Ichii Osamu, Kojima Masayasu, Nishi Yoshihiro, Mifune Hiroharu, Kamimura Ryozo, Matsumoto Mitsuharu, Suzuki Shusaku
Laboratory of Veterinary Anatomy, Department of Veterinary Medicine, Faculty of Agriculture, Kagoshima University, 1-21-24 Korimoto, 890-0065 Kagoshima, Japan.
Histochem Cell Biol. 2006 Aug;126(2):231-8. doi: 10.1007/s00418-006-0165-6. Epub 2006 Mar 3.
Ghrelin is a novel peptide hormone, originally identified in the rat and human stomach that plays various important roles. In the present study, we report the intra-renal localization of ghrelin in laboratory rodents. Kidneys from 3 month-old mice, rats and hamsters of both sexes were analyzed by immunohistochemistry. Positive signals were clearly observed in the epithelium of the distal tubules, whereas other segments of the nephron or interstitial cells, including juxtaglomerular cells, showed negative reactions. Pre-embedding immunoelectron microscopy revealed positive signals exclusively on the basolateral membrane in the distal tubular cells and in the collecting ducts. In addition, prepro-ghrelin gene expression was assessed by RT-PCR, and the expected 329-bp prepro-ghrelin mRNA was clearly detected in the kidney. On Western blot analysis, although a specific band for ghrelin (3 kDa) was not detected in the kidney, the expected band for prepro-ghrelin (13 kDa) was clearly detected in both the stomach and the kidney. This paper clarified the intra-renal localization of ghrelin.
胃饥饿素是一种新型肽类激素，最初在大鼠和人类胃中被发现，发挥着多种重要作用。在本研究中，我们报告了胃饥饿素在实验啮齿动物肾脏内的定位。通过免疫组织化学分析了3月龄雌雄小鼠、大鼠和仓鼠的肾脏。在远端小管上皮中清晰观察到阳性信号，而肾单位的其他节段或间质细胞，包括肾小球旁细胞，均呈阴性反应。包埋前免疫电子显微镜显示，阳性信号仅存在于远端小管细胞和集合管的基底外侧膜上。此外，通过逆转录聚合酶链反应（RT-PCR）评估前胃饥饿素原基因表达，在肾脏中清晰检测到预期的329bp前胃饥饿素原信使核糖核酸（mRNA）。在蛋白质免疫印迹分析中，虽然在肾脏中未检测到胃饥饿素的特异性条带（3 kDa），但在胃和肾脏中均清晰检测到前胃饥饿素原的预期条带（13 kDa）。本文阐明了胃饥饿素在肾脏内的定位。
