Na,K-ATPase is an integral membrane protein complex that hydrolyzes ATP to maintain the transmembrane gradients of Na+ and K+ found in most mammalian cells. The enzyme is comprised of an alpha and beta subunit. The alpha-polypeptide has been shown to be the catalytically active subunit, whereas the Beta-polypeptide appears to be necessary for the assembly and transport of the sodium pump to the plasma membrane. Na,K-ATPase alpha-1 subunit, in brain, is expressed in both neuronal and non-neuronal cells.