Differential Axonal Transport of Individual (Na,K)-ATPase α Subunit Isoforms in Rat Sciatic Nerve

All three isoforms of the α subunit of Na/K-ATPase are found in neurons, with each isoform displaying a distinct regional, cellular, and subcellular distribution. In situ hybridization studies with riboprobes specific for α1, α2 and α3 isoforms have demonstrated the presence of mRNAs for each of those isoforms in neurons (1–4). All neurons appear to contain α2 and α3 isoform mRNA, while some neurons also contain al mRNA. Glia contain only α1 and α2 isoform mRNAs (5). Electron microscopic immunocytochemical studies have demonstrated the presence of the (Na,K)-ATPase both at the node of Ranvier (6), and in the internodal axolemma of large myelinated fibers (7), though the ultrastructural distribution of individual isoforms along the axolemma of large myelinated fibers has not been unambiguously defined. These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.