THE NA,K-ATPASE HYPOTHESIS FOR BIPOLAR ILLNESS

A cellular model for bipolar illness is presented. It is propounded th at alterations in the activity of the membrane sodium- and potassium-a ctivated adenosine triphosphatase pump (Na,K-ATPase) may be responsibl e for alterations in neuronal excitability and activity. Specifically, a reduction in Na,K-ATPase activity can lead to both mania and depres sion by increasing membrane excitability and decreasing neurotransmitt er release, respectively. Supporting evidence is reviewed, and clinica l and research implications are discussed.