Carey H V, Hayden U L, Spicer S S, Schulte B A, Benos D J
Department of Comparative Biosciences, University of Wisconsin, Madison 53706.
Am J Physiol. 1994 Mar;266(3 Pt 1):G504-10. doi: 10.1152/ajpgi.1994.266.3.G504.
Polyclonal antibodies raised against purified bovine renal papillary amiloride-sensitive Na+ channels were used to localize Na(+)-channel proteins in mouse and piglet small intestine. Immunostaining using the avidin-biotin-peroxidase technique revealed epithelial Na(+)-channel epitopes localized to apical regions of villus enterocytes in jejunal tissues of both species. Anti-Na(+)-channel antibodies also stained apical borders of villus enterocytes in piglet ileum and apical borders of surface cells in the piglet distal colon. On immunoblots of jejunal, colonic, and renal tissues the anti-Na(+)-channel antibodies recognized one to three polypeptides of apparent molecular masses similar to those found in bovine renal epithelial Na(+)-channel protein (the 55-65, 110-116, and 150-kDa subunits). The antibodies also recognized a polypeptide in the 40- to 45-kDa range in mouse intestine, which is comparable to the 35- to 40-kDa subunit of a renal Na+ channel. The results demonstrate that epitopes comparable to those present in renal amiloride-sensitive Na+ channels are found in apical regions of absorptive epithelial cells in the mammalian small and large intestine.
用针对纯化的牛肾乳头氨氯地平敏感钠通道产生的多克隆抗体，来定位小鼠和仔猪小肠中的钠通道蛋白。采用抗生物素蛋白-生物素-过氧化物酶技术进行免疫染色，结果显示两种动物空肠组织中，上皮钠通道表位定位于绒毛肠上皮细胞的顶端区域。抗钠通道抗体也使仔猪回肠绒毛肠上皮细胞的顶端边界以及仔猪远端结肠表面细胞的顶端边界着色。在空肠、结肠和肾组织的免疫印迹上，抗钠通道抗体识别出一至三种表观分子量的多肽，这些多肽与在牛肾上皮钠通道蛋白中发现的多肽（55 - 65、110 - 116和150 kDa亚基）相似。这些抗体还识别出小鼠肠道中40至45 kDa范围内的一种多肽，该多肽与肾钠通道的35至40 kDa亚基相当。结果表明，在哺乳动物小肠和大肠的吸收性上皮细胞顶端区域发现了与肾氨氯地平敏感钠通道中存在的表位相当的表位。
