Physiological Functions of (Na⁺+K⁺)-Adenosinetriphosphatase (ATPase) Isozymes

Abstract

Since Sweadner demonstrated that there are two isozymes (α and α (+) isoforms) of (Na⁺+K⁺)-adenosine triphosphatase (ATPase) in the brain about 10 years ago, the isozymes have been extensively studied at biochemical and molecular levels. We started the studies on the isozymes of (Na⁺+K⁺)-ATPase soon after finding that pyrithiamin, an antimetabolite of thiamin is a selective inhibitor of the α (+) isoform. This review summarizes the previous studies on the isozymes of (Na⁺+K⁺)-ATPase, which are now classified into α1, α2, and α3.