Paxton W G, Runge M, Horaist C, Cohen C, Alexander R W, Bernstein K E
Department of Pathology, Emory University, Atlanta, Georgia 30322.
Am J Physiol. 1993 Jun;264(6 Pt 2):F989-95. doi: 10.1152/ajprenal.1993.264.6.F989.
To study receptors for angiotensin II, polyclonal rabbit anti-peptide antisera were prepared against the peptide QDDCPKAGRHC corresponding to amino acids 15-24 of the rat AT1A and AT1B receptors. Western analysis of rat tissues showed a major band of approximately 43 kDa. The antisera immunoprecipitated AT1-receptor protein produced in vitro. Immunohistochemical analysis of rat tissues showed intense staining of arterial and arteriolar smooth muscle. Other tissues that contained AT1-receptor protein included hepatocytes, the zona glomerulosa of the adrenal gland, and the smooth muscle of the bronchus, gut, ureter, and epididymis. In the kidney, intense staining was observed in all small arteries and arterioles. Both afferent and efferent arterioles contain approximately equal intensities of immunoreactive AT1 protein. The inner stripe of the outer medulla has a moderate level of receptors within thick ascending limb epithelium. Proximal tubular epithelium also expresses receptor protein. Glomerular immunoreactive AT1 protein is found within mesangial cells and varies in intensity among different rat strains. Lewis and Wistar rats demonstrated moderate glomerular staining, whereas the CD and Sprague-Dawley strains showed lesser levels of reactivity. The fact that glomerular mesangial cells are the primary locus of angiotensin II action within the glomerulus.
为研究血管紧张素II的受体，制备了针对与大鼠AT1A和AT1B受体氨基酸15 - 24对应的肽QDDCPKAGRHC的兔多克隆抗肽抗血清。对大鼠组织进行的蛋白质印迹分析显示有一条约43 kDa的主要条带。该抗血清免疫沉淀了体外产生的AT1受体蛋白。对大鼠组织的免疫组织化学分析显示动脉和小动脉平滑肌有强烈染色。其他含有AT1受体蛋白的组织包括肝细胞、肾上腺球状带以及支气管、肠道、输尿管和附睾的平滑肌。在肾脏中，所有小动脉和小动脉均观察到强烈染色。入球小动脉和出球小动脉所含免疫反应性AT1蛋白的强度大致相等。外髓质内带在厚壁升支上皮内有中等水平的受体。近端肾小管上皮也表达受体蛋白。肾小球免疫反应性AT1蛋白存在于系膜细胞中，且在不同大鼠品系间强度有所不同。刘易斯大鼠和Wistar大鼠肾小球染色中等，而CD大鼠和Sprague - Dawley品系的反应性较低。肾小球系膜细胞是肾小球内血管紧张素II作用的主要位点。
