Anti-Alpha 1 Na⁺/K⁺ ATPase Antibody

Na⁺/K⁺-ATPase, a membrane protein located on the plasma membrane of all animal cells, is involved in maintaining the Na⁺ and K⁺ gradients across the cell membrane¹. It is ubiquitously expressed in neurons and helps maintain normal neuronal function². The enzyme is composed of a catalytic α chain of 112 kDa. and α glycosylated β chain of 40–50 kDa. There are four isoforms of the α subunit (α1, α2, α3 and α4) and three isoforms of the β subunit (β1, β2 and β3) with different tissue distributions³.
 
The N-terminus is located on the cytoplasmic side of the membrane. There are four transmembrane segments in the first third of the polypeptide chain, a large cytoplasmic loop (LCL) comprising the second third of the chain and four to six transmembrane segments in the C-terminal third of the protein with the C-terminus also on the cytoplasmic side of the membrane⁴.
 
Na⁺/K⁺-ATPase abnormalities have been reported to be involved in several neurological diseases such as seizures, bipolar disorder, spongiform encephalopathy, and Alzheimer’s disease. Na⁺/K⁺-ATPase may also have implications in behavioral defects⁵.