Antibodies against purified epithelial sodium channel protein from bovine renal papilla

Monoclonal and polyclonal antibodies against amiloride-sensitive sodium channel protein purified from bovine renal papilla have been produced. These antibodies show considerable specificity in enzyme-linked immunosorbent assay (ELISA) and dot-blot assays and can immunoprecipitate radiolabeled channel protein. The polyclonal antibodies bind two sodium channel subunits on Western blots, namely, the 300- and 110-kDa polypeptides, and cross react with channel protein isolated from the amphibian A6 renal epithelial cell line. They can be used to immunoaffinity purify the channel in relatively high yield from a crude, detergent-solubilized bovine kidney homogenate. These antibodies should be useful in isolating the sodium channel gene, in studying the channel protein structure, in studying immunocytochemical localization, and in allowing purification of the channel from other tissue sources.